Creating the Prairie Xeriscape 9781550504613

Table of contents :
Front Cover
Half-title page
Title page
Book Copyright Information
Table of Contents
Preface
Part 1 – Xeriscape Fundamentals
Chapter 1 – Introduction
Chapter 2 – Design
Chapter 3 – Soil
Chapter 4 – Irrigation
Chapter 5 – Mulch
Chapter 6 – Lawns
Part 2 – Xeriscape Plants
About Part 2
Trees & Shrubs
Perennials
Annuals
Vines
Bulbs
Part 3 – Appendices
Chart – Trees and Shrubs
Chart – Perennials
Chart – Annuals
Chart – Vines
Chart – Bulbs
Index
Acknowledgements
Photograph Credits
About the Author

Citation preview

CREATING THE

PRAIRIE

XERISCAPE

2

Creating the Prairie Xeriscape

REVISED & UPDATED

CREATING THE

PRAIRIE

XERISCAPE SARA WILLIAMS

COTEAU BOOKS

© Sara Williams, 2013 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, without the prior written consent of the publisher or a licence from The Canadian Copyright Licensing Agency (Access Copyright). For an Access Copyright licence, visit www.accesscopyright.ca or call toll free to 1-800-893-5777. Edited by Roberta Coulter Designed by Tania Craan Typeset by Susan Buck Plan graphic drawings by Lavern Pratt; Plan color renderings by Jeff Wilson Printed and bound in Canada by Friesens Library and Archives Canada Cataloguing in Publication Williams, Sara, 1941Creating the prairie xeriscape / Sara Williams. -- Rev. & updated Includes index. ISBN 978-1-55050-461-3 1. Xeriscaping--Prairie Provinces. 2. Drought-tolerant plants-Prairie Provinces. 3. Gardens--Design--Prairie Provinces. I. Title.

SB439.8.W54 2013

635.9’52509712

C2012-906360-6

10 9 8 7 6 5 4 3 2 1

Available in Canada from: 2517 Victoria Avenue

Publishers Group Canada

Regina, Saskatchewan

2440 Viking Way

Canada

Richmond, BC, Canada

S4P 0T2

V6V 1N2

www.coteaubooks.com Coteau Books gratefully acknowledges the financial support of its publishing program by: The Saskatchewan Arts Board, including the Creative Industry Growth and Sustainability Program of the Government of Saskatchewan via the Ministry of Parks, Culture and Sport; the Canada Council for the Arts; the Government of Canada through the Canada Book Fund; and the City of Regina Arts Commission.

Contents

Preface

PART 1

Xeriscape Fundamentals

1 3

vii

CHAPTER 1



Introduction

CHAPTER 2



Design 9

CHAPTER 3



Soil 37

CHAPTER 4



Irrigation

47

CHAPTER 5



Mulch

65

CHAPTER 6



Lawns

77

Xeriscape Plants

99

PART 2 CHAPTER 7



Trees & Shrubs

101

CHAPTER 8



Perennials

167

CHAPTER 9



Annuals

227

CHAPTER 10



Vines

281

CHAPTER 11



Bulbs

291

Contents

5

s PART 3

Appendices

307



Ornamental Plant Charts

308



Index

328

Acknowledgements 335

vi

Creating the Prairie Xeriscape

Image Citations

335

Preface The original edition of Creating the Prairie Xeriscape was published in 1997, a time when the term itself was largely unknown and the concept considered a bit off the beaten track and out in left field. In the intervening years, prairie dwellers have become much more aware of the need to conserve water and xeriscape has become a household term. The lower maintenance and reduced inputs of xeriscape have also had an impact on the way we garden. Xeriscape has been embraced not only by home gardeners but by the landscape industry. Mulching is now considered standard practice, garden centres have begun to label plants as “drought tolerant”, and one can see a general reduction in lawn size and more and more front yards are being xeriscaped. On the flip side, many of the by-products used for mulch that were considered waste, and given away free or sold at cost, 15 years ago, are now being processed specifically as mulch for the landscape industry and have a cost to them. More positively, while the original edition of Creating the Prairie Xeriscape contained about 200 plant species, the current one describes over 209 genera, 397 species, and 865 cultivars or varieties – all of which are drought-tolerant. Our palette of trees, shrubs, perennials, annuals, bulbs and vines has definitely increased! Xeriscape has become not only less challenging, but more interesting. It’s easier than ever to create your own prairie xeriscape. Enjoy!

vii

To the erstwhile “young un’s” who welcomed me as a student and whose friendship, generosity of spirit and knowledge I value: Cathy, Chris, Erl, Jackie, Jocelyn, Maureen, Todd, and Yvonne; and also to Allan Daku and Hugh Skinner.

PART 1

Xeriscape Fundamentals “People are delighted with a landscape that is pleasing to the eye, kind to the CALAM the environment environment and and undemanding undemanding in in time, time, chemicals chemicals and and water.” water.” — — DAVID ATTRIBUTION

PREVIOUS PAGE: Combining a hard surface with a drought-tolerant mixed border saves both wear and water. The recycled brick walk lends it an Old World look and a sense of permanency.

CHAPTER 1

Introduction Creating the Prairie Xeriscape Xeriscaping is an environmentally friendly approach to your yard and garden that leaves your piece of the world in as good or better shape than when you assumed stewardship. As well, a xeriscape yard frees you from much of the repetitive maintenance we have come to accept as normal in conventional landscaping. Instead of weeding, watering and mowing, you’ll be able to spend quality time in your garden, doing whatever gives you pleasure: designing, planting or just enjoying your surroundings.

What Is Xeriscape? The word xeriscape was coined from the Greek xeros, meaning dry and scape, from the Anglo-Saxon word schap, meaning view. The word is misleading – it conjures up visions of a dry, desertlike landscape, but in fact a xeriscape landscape is as colourful and interesting as a conventional one. It is not rocks and plastic. It is high-quality, attractive landscaping. Xeriscape is not a limited style of landscaping, but an approach that can employ many and varied styles. The difference lies in the way water is used. There are many styles and approaches to xeriscaping: naturalization using native plant material; cottage gardening; layered mixed borders; or more conventional designs using

In xeriscape design, plants with similar water needs are grouped together and watered accordingly.

plants both introduced and native. It can be applied to condominiums, urban yards, farms, acreages and public spaces ranging from libraries and schools to parks and parking lots.

Introduction

3

The Principles Xeriscape is a concept that includes several principles. Many prairie gardeners have been using some of these practices for years. The principles and practices of xeriscape are what sound gardening is all about.

Design for water conservation Xeriscape yards provide us with beauty, privacy and protection from the elements, but they also conserve water. Plants with similar water needs are grouped together and watered appropriately. Grading directs water to planting beds or pond-like areas where it can be held until needed.

Improve soil Improving the ability of your soil to hold water and nutrients before planting goes a long way to reducing maintenance and inputs later. Xeriscape provides practical solutions to soils that Dry stream beds direct excess water to planting beds or pond-like areas where it can be held until needed.

are too shallow, too heavy, too light or lack organic matter.

Reduce lawn areas Reducing the area of lawn, changing its shape to conform to irrigation patterns, using more drought-tolerant grasses and changing the way you water, mow and fertilize reduces your labour considerably and saves water.

Pretty in pink! This zoned border contains moderately drought tolerant plants such as zinnia and mallow.

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Creating the Prairie Xeriscape

Efficient irrigation Much of the water now applied to our landscape is either not needed or is wasted. Understanding how and when plants need water, where most wastage occurs and how irrigation systems work will not only save you time and money, but it will also conserve water and reduce maintenance.

Mulching An organic mulch is placed on the soil surface to conserve water, reduce weeding and improve the soil. There are many types of mulching material, from newspapers to grass clippings to post peelings.

Appropriate plant selection We think of our water-intensive landscapes as normal, but the disparity between the water needs of the plants in our landscapes and natural precipitation is perhaps nowhere greater than on the prairies. In many areas of the prairies, average annual precipitation is less than 30 cm (12 in.), yet many of our landscape plants are more suited to the moist, green gardens of England. There is an extensive selection of drought-tolerant trees, shrubs, perennials, vines, bulbs and annuals that are hardy on the prairies. Some of these may already be a part of your landscape, but because they are located beside less droughttolerant plants, they may be receiving a lot more water than they need.

Why Xeriscape? Landscapes composed of plants with water needs proportional to natural precipitation are easier and cheaper to maintain and are much more likely to survive drought and water restrictions. One of the greatest benefits of xeriscape is reduced maintenance. Liberated from much of the drudgery of weeding, mowing and watering, we can spend our garden time on more creative pursuits. While there is no such thing as “no maintenance,” xeriscaping does offer “low maintenance.”

Less watering Drought-tolerant plants are able to survive with less water. Once a mulch layer is in place and plants are grouped according to their water needs, less water and less frequent watering are needed. Soil amended with organic matter is able to hold a greater volume of water, again resulting in less frequent watering. Irrigation is more efficient, reducing water waste.

Rain barrels can be decorative as well as useful. Many of those on estate gardens in the British Isles are highly ornate. On the prairies we may have to settle for plastic, fibreglass, metal or oak barrels.

Introduction

5

Less weeding The mulch layer greatly reduces the time spent weeding. Weeding is also reduced because you are no longer watering and encouraging the growth of weeds in “non-target” areas. Denser plantings of ground covers leave less space for weeds. A higher mowing height in lawns results in deeper-rooted and more vigorous grass, which is better able to compete with lawn weeds.

Less fertilizing Drought-tolerant plants generally require fewer nutrients, reducing the need for fertilizer. As well, deeper watering encourages deeper rooting, allowing roots to obtain nutrients from a larger volume of soil. Because the soil has been amended with organic matter, more nutrients are available within the soil. Mulching also reduces fertilizer inputs because as the mulch layer slowly decays over the years, still more nutrients are released into the soil. Leaving clippings on the lawn also lowers fertilizer needs. The primary functions of mulches are to conserve water, reduce weeds, and improve our soils by the addition of nutrients and organic matter.

Less pruning Drought-tolerant plant material that is watered deeply but less frequently generally has less succulent growth and therefore requires less pruning. By leaving trees and shrubs in their natural form (rather than hedging), pruning and trimming are further reduced. Finally, knowing the mature height and width of a tree or shrub and planting it in an appropriate site reduces pruning substantially.

Less mowing By reducing the area of grass to that which is actually used as lawn and replacing the remainder with drought-tolerant ground covers or hard surfaces, you eliminate a great deal of mowing. The grass that remains is mowed less frequently because a xeriscape lawn is usually cut at 10 cm (4 in.) rather than at the conventional 7.5 cm (3 in.). Less-frequent mowing results in a deeper root system able to withdraw water from a greater volume of soil. As well, slightly taller grass will shade the soil surface, reducing evaporation.

Fewer pesticides Succulent plant growth encourages disease because cells are thinner and more easily penetrated by disease organisms. Since Xeriscape reduces the need for fertilizers and pesticides, making our landscapes safer and more environmentally friendly.

6

Creating the Prairie Xeriscape

drought-tolerant plants generally require less water and fertilizer, their growth is less succulent, making them less vulnerable to disease. As well, because the xeriscape landscape encourages biodiversity – the use of a wide range of plants – rather than a

monoculture of just a few types of plants, it also encourages insect predators and a balance of insects. In addition, the use of drip irrigation leaves foliage dry, reducing fungal diseases. Finally, there are fewer weeds (which often act as alternate hosts for both diseases and insects), which in turn lowers the incidence of pest problems.

The Rewards The rewards of xeriscape are many. Lower maintenance means spending quality time in your landscape. Working creatively is so much more satisfying than the drudgery of battling pestilence or pushing a lawn mower. Xeriscape also means a lower water bill. Water savings vary between 20 and 80 percent of a pre-xeriscape landscape. Along with conserving water, fewer pest control strategies and fertilizers are needed. And if drought should occur and water restrictions are imposed on the landscape, your landscape will survive.

How to Use This Book The extent to which you follow xeriscape principles is one of choice based on philosophy, time, cost and your use of the landscape. Apply these principles to the degree that you feel comfortable. Use any or all of them. They are adaptable and can

Drought-tolerant pavement plantings such as these soften a hard surface, making an inviting patio even more inviting.

be modified to fit the household use of your yard, your personal philosophy, your sense of what is beautiful and the time and money you wish to commit. This book is designed to allow you to create a prairie xeriscape of your own. Read in its entirety or used as a reference manual, it is intended to guide homeowners, landscape professionals, developers and municipal planners through the implementation of xeriscape principles.

Parts of the Book Each of the following chapters in Part 1 is based on a xeriscape principle. Applicable maintenance is discussed within each chapter. Part 2 gives detailed descriptions of the hardy, drought-tolerant plants that form the prairie xeriscape, including trees and shrubs, perennials, vines, bulbs and annuals. Don’t overlook the reference charts at the back of the book. They provide an “instant” landscaping guide to the light requirements, height and colour of individual plants.

Introduction

7

Designing Your Xeriscape Begin with the design chapter. Drawings and photographs provide a visual picture of xeriscape possibilities. Turn to Part 2 of the book when you need information about a particular plant and when you’re ready to get down to selecting specific plant material for your prairie xeriscape. It includes detailed information, almost all with photographs, of the trees and shrubs, vines, bulbs, perennials and annuals, that form the prairie xeriscape: approximately 200 genera, 400 species, and almost 900 varieties. All of these plants (except, of course, the annuals) are considered hardy at least to zone 2b unless stated otherwise.

G

Watch for this icon. It accompanies the plant selections

that are extremely drought tolerant. Once “established” (i.e., by A xeriscape landscape is comfortable, attractive, and saves time and money. Embrace change and begin with the area of your yard with which you are most dissatisfied. Then relax and enjoy the fruits of your labour.

their second or third growing season), they will seldom if ever need supplemental water. Among this group are caragana, clary sage, Cota tinctoria, Gaillardia, Yucca glauca and lilac. The remainder of the plants listed are moderately drought tolerant, which means that during dry, hot, windy periods, supplemental water will be needed. (A third category – not included in this book – are those plants that will always need supplemental water, such as tea roses, hostas, primroses, hydrangeas and birch.) Much of the information in the plant descriptions is also summarized in reference charts at the back. These charts are particularly useful if you are looking for a tree or shrub of a particular height or a flower of a particular colour. Within each chapter in Part 2 and in the reference charts, the plants are listed alphabetically by botanical name. (If you don’t know the botanical name, you will find all plants listed by their common names in the index.) Each plant entry is accompanied by one or more colour photographs.

“One of the key principles of xeriscape design is grouping plants with similar water needs together to conserve water.”

8

Creating the Prairie Xeriscape

CHAPTER 2

Design Designing Your Xeriscape This chapter explains the basics of landscape design, with emphasis on xeriscape principles that save water and result in a low-maintenance landscape. It leads you through the process of design, step by step, from paper to reality. Using the plant descriptions in Part 2 of this book as a reference, you can then fill in the details of garden walls, floors and ceilings. Proper placement of plants is critical. One of the key principles of xeriscape design is grouping plants with similar water needs together to conserve water. Plants are therefore placed in beds and borders rather than in individual or "scattergun" plantings. Xeriscape design uses mixed plantings of droughttolerant trees, shrubs, perennials, bulbs, vines and annuals within a single bed, thereby creating a "layered look" and grouping plants with similar water needs. This chapter also includes different approaches to xeriscape, complete with landscape designs for mixed layered borders; winter colour and birds; large-scale landscaping using mass plantings in rural yards; and a new concept in shelterbelts.

Intensively used areas of your outdoor living space should be “floored” with some sort of hardscape such as brick or paving blocks. The surrounding plantings of drought-tolerant plant material need little water and have low maintenance requirements.

Introduction to Landscape Design Many decisions go into landscape planning. You may do the design and installation yourself or hire professionals, but it is your yard. Like any other endeavour, the more you know, the more comfortable you'll be in making these decisions. Consider the extent to which you wish to carry out xeriscape principles. Do you want to make these changes immediately and to your entire yard or slowly and to only portions of your yard? Some people begin with the area with which they are most dissatisfied. Others find the front yard the easiest to begin with.

Design

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Consider the topography and microclimates of your landscape. Sometimes problem areas such as slopes need to be modified to make the landscape a more hospitable place for both your plants and yourself. Some areas of your yard may require careful selection of plant material appropriate to an existing microclimate.

Why Are You Doing This? The focus in a xeriscape landscape is the emphasis on water conservation; lower maintenance is a bonus. We want our landscapes‚ whether conventional or xeriscape‚ to be functional as well as to provide us with beauty, privacy, protection from the This bank has been terraced and planted with extremely drought-tolerant bergenia and juniper, preventing erosion and conserving water.

elements, convenience, safety and low maintenance. Beauty is, of course, in the eye of the beholder. What you like is very personal and probably different from your neighbour. And so it should be! One of the reasons we plant trees and shrubs and build fences is to preserve our privacy. This is particularly true of our backyards, which we use as outdoor living space. Remember too that whatever you see outdoors from your house or yard is also part of your landscape, whether you happen to own it or not. It is your choice to include or exclude views through landscaping. If a neighbour has an exceptionally beautiful tree or yard, emphasize it by "framing" it with other plant material. If there is an ugly shed or garage, use plants to screen or hide it. In the words of architect Frank Lloyd Wright: "The physician can bury his mistakes, but the architect can only advise his client to plant vines" (or a tree, shrub, trellis or fence).

Our landscape goes beyond what we own. Exceptional views can be emphasized through the careful pruning of existing trees, a concept termed enframement.

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Creating the Prairie Xeriscape

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Landscaping provides protection from the elements. We use plant material to modify our environment, creating microclimates that are warmer, calmer and that conserve moisture. Trees with large canopies such as Manitoba maple, hackberry and green ash provide shade. So can arbors or decks laced with vines. Dense shrubs and coniferous trees, placed to buffer prevailing winds, increase our comfort and decrease our heating bills. Shrub plantings reduce dust, traffic glare, pollutants and, to a lesser extent, noise. Be flexible when planning your landscape. Allow for a variety of activities to take place in a single area. Consider recreational and social use of space and allow for changing use of outdoor areas as the family grows and changes. What might begin as a sunken sandbox/play area could later be converted to a sunken patio or pond area.

Starting Points The Hardscape

One of the reasons we landscape is to create a beautiful environment. And beauty is very much in the eyes of the beholder...

Convenience and safety are important elements of landscaping. The placement of walkways and gateways should be determined by a logical "traffic" pattern through different areas of the yard. Both should be wide enough to accommodate the largest piece of machinery (e.g., rototiller, snow blower) that has to move over or through them. A minimum width of 1.25 m (4 ft) to accommodate two people walking side by side is recommended. Steps should have treads of 30 cm (12 in.) and risers of 15 cm (6 in.). Steps and walks should be non-slippery and well lit. Driveways should be wide enough to allow for vehicles as well as people entering and leaving them. Plantings along driveways can be used to soften harsh concrete or asphalt, but should be low enough not to block the view of the driver. Nor should they trap snow, hinder snow removal or be vulnerable to damage caused by snow dumping or salt used to melt ice. Avoid hedging along driveways and sidewalks as it can make snow removal difficult if not impossible. To reduce areas of concrete or asphalt – and the amount of time spent shovelling snow – place garages as close to the property line as possible.

Placement of Plant Materials: The Layered Look Proper placement of plant materials is always challenging but is especially so in xeriscape design. By grouping plants with the

Patios are most conveniently placed adjacent to the house and close to the kitchen. Walkways should follow a logical “traffic” pattern through your yard.

same water needs in the same bed, you conserve water.

Design

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Throwing a curve at shelterbelts Use those trees and shrubs designated in More than a century ago, surveyors laid out the

Part 2 of this book as extremely drought toler-

prairies in a grid and we still think in terms of

ant or those recommended by the Prairie Farm

sections and half-sections. Living on the prai-

Rehabilitation Administration (PFRA). Maintain

ries gives us a geometrical mindset. Everything,

the within-the-row and between-the-row spac-

including shelterbelts, is done on the square.

ings recommended by your supplier. Design

Shelterbelts are planted for utilitarian

the closest two or three rows as “groupings”

reasons: to provide wind protection, conserve

of a single species rather than using one plant

moisture, protect buildings and farmyards,

species per row. (Note: poplar may be removed

conserve heat and prevent topsoil from blowing

once green ash has become established.) Then

away. It is hard to imagine what our landscape

curve the entire shelterbelt to fit your farm or

would be like without them.

acreage yard.

But they are almost invariably laid out in

The initial planning and planting will take

rigidly straight lines with one tree or shrub

a little more time and effort, but contrary to

species per line and little consideration for aes-

popular opinion, cultivators can make curves.

thetics. Yet there is no reason why they cannot

The payoff? It’s the view from your deck, patio,

be beautiful as well as functional.

driveway or kitchen window.

Over the past few decades, thoughts on

All of the functions a shelterbelt was

shelterbelts have begun to change. Wildlife

designed for are retained, but the groupings

and “agro-forestry” plantings have become

will present a visual image of changing flow-

accepted. It’s time we threw a curve at the

ers, fruit and foliage through the seasons. You’ll

prairie grid and added beauty.

have gained the dimensions of colour, scent, songbirds and fruit.

By throwing a curve at shelterbelts and using groupings of drought tolerant shrubs, you gain the dimensions of colour, scent, songbirds and fruit.

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Creating the Prairie Xeriscape

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For visual interest and variety, develop mixed borders with a layered look. A mixed border is composed of a mixture of plants: trees, shrubs, annuals, biennials, perennials, bulbs and even vines. The border itself is generally (but not always) free-form and curved rather than formal with straight lines. Curved beds are more informal, can be made to "fit" any space and are more in keeping with today's casual ambiance. When planning, use a garden hose to determine the curve. Ensure that your lawn mower will fit the lawn side of curved beds. Add plants of various heights or layers to this concept and you have a mixed layered border. The different layers provide year-round interest in terms of height, colour and texture. The highest layer consists of a backbone of taller shade trees or conifers. Some of these may already exist in your yard and have merely to be incorporated into a new bed or border. In small urban yards, the dominant feature of a mixed layered border may be a single crabapple, plum or hawthorn. In larger

Perennials useful for massed beds:

• Artemisia ‘Silver King’ • perennial cornflower • tawny or lemon daylily • blanket flower • ‘Laurin’ goldenrod • goutweed • snow-in-summer • yarrow Ornamental grasses useful for massed beds:

• blue fescue • blue lyme grass • ‘Skinner’s Golden’ bromegrass • ribbon grass

rural landscapes, these borders may be several hundred metres long and include many trees and shrubs. Trees and shrubs should be planted in beds or groupings rather than in a "scattergun" pattern. A yard in which trees and shrubs have been planted singly here and there within the lawn can be an obstacle course in which to play or socialize. The placement of plants also affects maintenance, particularly ease of mowing. Mowing around a single large bed is much easier than mowing around a multitude of smaller beds or scattergun-planted trees. Placing trees and shrubs around the perimeter of our yards has advantages. It allows us to view them in their entirety from the lawn, patio or deck while providing maximum screening for enclosure and our sense of privacy as well as reducing wind, noise, glare and dust. They serve as a visual backdrop for flower beds, giving the illusion of more space, while leaving room for "people" activities. Trees are also positioned to provide shade for specific areas such as decks, patios, play areas and dog runs. Below the trees are taller shrubs, usually 1 to 2 m (4–6 ft) in height. For greater visual impact and ease of maintenance, these are planted in informal groupings of the same type of shrub. According to ancient Oriental traditions, odd numbers are

Daylilies and perennial geraniums, placed in front of trees and shrubs, form part of a mixed layered border composed of moderately drought tolerant plant material.

supposed to have more visual impact than even, so traditionally – but not necessarily – these groupings consist of an odd number such as three, five or seven, depending on the overall size of the shrubs and the border. These are generally placed towards the back of the border in relation to where it is usually viewed.

Design

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Large-scale landscaping: Mass plantings in rural yards Although the principles are the same, land-

and informal. They serve as a transition zone

scaping on a large scale is different. Of course

between the more manicured part of the yard

the space is greater, but as well, water con-

and the less manicured portions.

servation and reduced maintenance assume

Plants used in these beds should not only be

a larger role. Mixed layered borders and mass

drought tolerant but may also be selected for an

plantings

ability to reseed or an aggressive growth habit.

of

drought-tolerant

perennials,

ground covers and ornamental grasses are two approaches to consider.

Dead foliage on herbaceous plants in the mass plantings can be left standing in the fall

Mass plantings can be used to define and

to act as its own windbreak and snow catch-

separate the intensively landscaped area of

ment area. Snow will pile up to insulate the

your farm or acreage from the non-irrigated

plants over winter and provide added moisture

rough grass or bush beyond. A single large bed

in the spring. The bed can then be mowed in

can contain one or several different group-

early spring.

ings. The beds themselves are usually curved

All of the trees and shrubs in this rural mass planting are extremely drought tolerant: Scots pine, Colorado spruce, Amur maple, lilacs, shrub roses, poplar and sea buckthorn. The entire planting is mulched with post peelings.

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Creating the Prairie Xeriscape

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Also, below the canopy trees but towards the centre and front of the border is a layer of lower shrubs or tall perennials, usually 0.5 to 1.25 m (2–4 ft) in height. On the edge of the border and visually tying it together is a ground cover layer, generally less than 0.5 m (2 ft) in height. This layer consists of perennials and low shrubs. Shorter flowering plants are usually placed in pockets where they can be appreciated from the direction from which the border is viewed.

Scale, Focal Points and Unifying Elements Scale refers to the relative size of plant material in relation to the size of the house and lot. Just as large, overstuffed furniture tends to make a small room appear even smaller, large trees will further reduce the apparent size of a small house. Conversely, using smaller trees will make a large house appear even larger. It is important that the size of plantings be in proportion to the size of buildings. Before you plant, know the mature size (height and width) of plants, especially trees and shrubs. In smaller areas, trees, shrubs, flowers and ground covers that are not only small to medium in overall size but also have small- to medium-sized leaves and flowers are more satisfactory. Each major area of a yard should contain a focal point or visual point of interest. This could be a particularly beautiful tree (such as a Swiss stone pine or 'Spring Snow' flowering crabapple), a vine-draped trellis, pond, birdbath, flower bed, formal herb garden, piece of sculpture or sundial. To unify the landscape as a whole, repeat plant species within an area and from one area of the yard to another. One might

Each major area of your yard should contain a focal point, a visual point of interest. What could be more appropriate than a sculpture of a gardener?

repeat a grouping of shrub roses in several places, a favourite vine such as ‘Rosy O'Grady' clematis, daylilies or an underplanting of Waldsteinia or dwarf fleeceflower. This does not imply that one side of the lot should be a mirror image of the other, but rather that several species form a theme of plant material around which the total design is based. Some of us delight in the development of a "horticultural zoo," compulsively seeking out the new, the unusual, the justpossibly-hardy. For the less demented, just twenty plant species may suffice in a smaller yard. Non-plant material – the hardscape of walkways, fences and walls – should also be repeated, thereby unifying house and

Things change Keep in mind that the micr oclimates noted in your site analysis are what exist now. They will change over time as your plantings grow and provide shelter from wind and as smaller trees grow to the point wher e they provide shade.

yard. If your house is constructed of brick, why not use brick for walks, patios and retaining walls? If you own a cedar house, use cedar for garden benches, lamp posts, fencing or trellises. If your

Design

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Winter colour, birds and xeriscape design Designing for the birds involves placing a bor-

this is a bird’s eye view we’re considering here –

der where the housebound gardener will derive

for cold-hardy cats and other predators.

the most pleasure from the visiting birds and the colour of the winter landscape and where the birds will have food, shelter and safety. A well-located feeder is a bonus for both birds and gardener. What we’re after is a border that is easily viewed from the sidewalk or inside the house and that has a “layered look.” Begin with one or two canopy trees to provide shelter, a safe perch with a good view and perhaps seed, fruit or rough, furrowed, insect-containing bark for foraging. A middle layer would have shrubs varying from 0.5 to 1.5 m (2–5 ft), selected for shelter, seeds and berries. The lower layer would consist of ground cover, also selected for provision of food or shelter. The border as a whole is placed adjacent to

Begin with what you have If you have an established yard, you probably already know which trees and shrubs attract birds during the winter. Crabapple is obvious. Less obvious are pine, spruce and Russian olive. If these plants are easily viewed from windows where you spend your wintertime, then begin with them. The average urban lot will need only one or two canopy trees for a winter bird border. A rural yard can be more expansive. Think of plants that retain their fruit through fall and all or part of winter. Colour is an added bonus in a part of the world where

the

towing

season

exceeds

the

growing season.

a lawn or other open area that is easily viewed –

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house is faced with stone, why not use flagstone for your walks, patio flooring or garden walls?

Bylaws

Plants for the bird-friendly winter landscape Canopy trees

Prior to any landscape construction, major plantings or build-

Green ash, crabapple, hawthorn,

ing, find out about local bylaws. These may concern the use of

Manitoba maple, bur oak, Scots pine,

plants now classified as noxious weeds; what may be planted

Colorado spruce, Russian olive.

or built on boulevards; lighting requirements; distance within

Taller shrubs

property lines on which construction is permitted; required

Buffaloberry, chokecherry, elder,

fencing around pools; management of drainage patterns; and

honeysuckle, lilac, pincherry,

even the overhang of trees onto neighbouring property. A phone

saskatoon berry, wolfwillow.

call to city hall or the rural municipality office, before you begin,

Shorter shrubs

can save a lot of grief.

Currant, gooseberry, juniper,

Also ensure that your property lines are where you think

shrub roses, snowberry.

they are. A survey is less costly and less emotionally exhaust-

Ground covers

ing than constructing a fence or planting a tree-shrub border

Manitoba grape, creeping juniper,

only to find you have encroached on a city boulevard or a neigh-

Virginia creeper.

bour’s lot. Check into any utility easement that may cross your property and find out about bylaws that restrict the height of

Annuals Barley, corn, sunflower, wheat.

fences (especially on corner lots) or their placement towards the perimeter of your property.

Main Divisions of the Home Landscape Yards have conventionally been divided into three main use areas: the public or entrance area, the service or utility area and the private area. Although these have long been discussed as separate entities, in reality they are usually somewhat merged.

The Public Area In North America, the front yard is usually considered a public or entrance area. Highly visible, it should be inviting and remain attractive with minimal maintenance. Using xeriscape principles to their full extent in a front yard can be both challenging and creative and will certainly grab the attention of your neighbours. Conventional lawn areas that are seldom if ever actually used as lawns can be entirely replaced with mixed beds of more drought-tolerant shrubs, perennials and ground covers. Street numbers or name plates should be well lit, not obscured by plant material and large enough to be visible from the street or road.

Walks and driveways Centred front walks date from the era when garages were located at the back of the lot. Most garages are now attached to the

Street numbers should be prominent and well lit. A container of annuals on the front landing draws visual attention to the front entrance.

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house. Place the sidewalk parallel and next to the driveway and from the driveway to the front door, following the logical foot traffic pattern. This avoids cutting up and visually shrinking the front yard. To soften a sidewalk, gently curve it and plant low evergreens, ground covers or perennials adjacent to it to bring it "into the landscape." Choose plants that are drought tolerant, non-invasive and will not interfere with snow removal. The minimum grade across a driveway should be 2 centimetres per metre (0.25 in/ft). This ensures adequate drainage and minimizes standing surface water, which would otherwise be lost to evaporation. The grade should direct water from the driveway onto planting beds. If the concrete is slightly textured, it is less slippery when wet and less reflective, thus creating a more hospitable environment for people as well as nearby plants.

Foundation plantings Foundation plantings are those near the house which give the illusion that the house is a part of the natural landscape. They should achieve visual balance without formal symmetry or a mirror image. Plant shrubs and trees as groupings rather than having narrow, monotonous lines of the same plant parallel to the house. Pay particular attention to the mature height and width of the plant material used. A 1 m (3 ft) Colorado spruce planted in front of your picture window will mature to 12 to 15 m (40–50 ft), fully blocking the view you once had. Dwarf evergreens are a better option. Because your front yard is seen throughout the year by many people, think in terms of the winter landscape when selecting plants. Use evergreen plantings and deciduous trees and shrubs with colourful bark or retained fruit, which are attractive and may attract birds. (See "Winter colour, birds and xeriscape Think in terms of their ultimate size and their winter landscape value when selecting foundation plantings for your front yard. Dwarf evergreens are ideal. Dwarf blue spruce (Picea pungens ‘Glauca ‘Globosa’) (above) or birds nest spruce (Picea abies ‘Nidiformis”) (below) both work well in this role as does mugo pine ‘Slowmound.’

design" on p. 16.) Use larger, heavier shrubs at the corners of the house. Planting a small tree will extend the width of the house, soften corners and draw the house into its setting. Remember the idea of scale: a large, two-storey house will need larger trees and shrubs than a bungalow. Trees and shrubs should be planted 1 to 2 m (4–6 ft) from foundations. Although this seems a wide expanse when the landscape is young, small plants do mature. This distance gives them room to grow and the homeowner space in which to paint siding, wash windows and make repairs. At this spacing, roots

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are less likely to interfere with foundations, plants are less likely to "bump their heads" under the roof overhang and roots are more likely to catch rainwater. Plants will also benefit from staying out of the hot, dry microclimate of reflected heat and light from white or reflective aluminum siding or stucco walls. This is especially important during their first few years when their root systems are relatively small and less able to absorb large quantities of water.

Flower beds Flowers require higher maintenance than trees and shrubs. Depending on how and where you wish to spend your garden time, you may wish to limit the number of flower beds in the front yard or you may decide to throw caution to the wind and replace the entire lawn with flowers. Often a small bed or a container of annuals on the front landing or an attractive hanging basket is all that is needed to draw visual attention to the front entrance and announce a cheerful welcome. If your house faces north, use xeriscape plants appro-

Xeriscape front yards can by simple yet effective. Here broad steps lead to the front door, the street number is prominent, and bright red geraniums bid the visitor a warm welcome.

priate to shade. If it faces south, use annuals tolerant of hot, dry conditions. Plants in containers will need more frequent watering than those in the ground. Increasing the organic matter in the soil mix will increase its water-holding capacity.

Service or Utility Area This is the catch-all term for everything from the clothesline to the dog run. The utility area may include the garage, garbage containers, storage sheds, greenhouse, cold frame, compost pile, vegetable garden, a pad for a recreational vehicle and a satellite dish. These structures are sometimes located in a single area, separated and screened from the remainder of the lot; they may be in several different areas as convenient; or they may be part and parcel of the backyard and family living space. When planning service areas, consider accessibility to back lanes and the occasional delivery of bulk materials such as manure. If the utility area is subjected to heavy wear, think about using a hard surface such as concrete, gravel or brick. If the hard surface covers a large area, grade it so that water is directed to plantings. If the area is not pleasing to look at, consider screening it with plants (vines, hedges or shrubs); a fence, wall

Garbage cans are necessary but hardly objects of beauty. Placed in the back lane they do what they are supposed to do, out of sight of the backyard.

or lattice; or a combination of these. Install power, gas and water to outbuildings such as garden sheds or greenhouses prior to landscaping and mark the position of the lines.

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The Private Area The private area is almost always in the backyard. It is the outdoor living area for you, your household and guests. It is usually fenced and screened for privacy.

Decks and patios An area intended for more intensive use is generally located immediately next to the rear entrance of the house, close to both the living room and kitchen. Ideally, it's an extension of the indoor living area into the outdoors and at the same level as the indoor living area. It usually has a hard surface (wood, brick, stone or concrete) and takes the form of a deck or patio. Steps from a deck or landing should be wide enough to accommodate at least two people. They can also provide extra seating when needed.

Decks originated in areas where houses are often built on hillsides or foothills overlooking oceans, valleys or large lakes, so that what is ground level on one side of the house becomes the second floor on the other. Decks were designed to provide a view while maintaining privacy and to take advantage of the natural contours of the land. Unfortunately, architectural styles do not always move gracefully from one geographic area to another. In a mostly flat land like the prairies, a raised deck is open to wind and wind-carried grit in early spring from surrounding agricultural land. In urban areas, the view from the deck is usually limited to, at best, a neighbour's house and at worst, a freeway. And it is usually anything but private – you are able to peer into your neighbours' yards and your neighbours (from the sides and perhaps the back) can see everything that happens on your deck. So, if it's not too late, consider alternatives – a patio, a sunken patio or a deck of less than a metre (a few feet) in height – or at least effective screening against sun, wind and neighbours. Whether you decide on a patio or a deck, ensure that it is large enough to function as an entertainment area: about 3.5 x 4.5 m (12 x 15 ft). A deck should be an outdoor room capable of seating six to eight adults and be roughly equivalent in shape

This small patio, close to the house but cozily situated amidst a mixed layered border, is an ideal spot for a quiet glass of wine at the close of the day.

to your living or dining room – more square than long and narrow. Humans tend to gather in groups that are oval or circular (around a dining-room table or in a living room) and a deck that is the length of your house but only 1 to 1.5 m (4–5 ft) wide does not lend itself to socializing. If the deck or patio is only slightly higher than the surrounding lawn and easily accessible with broad steps, it is easier for larger groups to spill over onto the adjoining lawn. Flooring may be wood (if a deck) or patio squares, cement,

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stones or bricks laid on sand and level with the lawn. As in the front yard, repeating the same construction materials in the patio or deck that are used in the house lends a sense of unity to the landscape. Containers of plants can break up large expanses of hard surface while adding colour. Vines help to visually lower a raised deck, pulling it into the landscape. They can also be used effectively as ceilings over decks and patios, lending shade and privacy.

The backyard A larger area, intended for less intensive use, is adjacent to the deck or patio and easily accessible from it. It is a place for the family or, on occasion, a large number of guests to gather for a special occasion. It is usually level, grassed and the scene of a variety of social and recreational activities. As in the front yard, avoid a scattergun planting of trees and

Containers of plants can break up a large expanse of cement while adding texture, colour and scent.

shrubs. It limits use of the lawn, makes the area appear visually smaller and more cut-up, hinders mowing and increases maintenance. It is generally appropriate to use curves rather than straight lines to separate lawns from flower, tree and shrub borders. A border that curves gently out of sight towards the edge of a property gives the illusion of greater distance and a larger yard than actually exists. Flower beds may be separate from tree and shrub plantings or part of a mixed layered border that includes annuals, biennials, perennials, bulbs and vines, as well as trees and shrubs. Raised beds are easy to work in, delineate and limit the space in which the soil is to be amended, are well drained, involve less bending and stooping on the part of the gardener, usually have fewer weed problems and warm up quickly in the spring. Aesthetically, they are more visible than beds at ground level, especially for alpine plants that are by nature tiny and low. These beds add interest by varying height. If placed around a patio, they provide wind protection for the patio area, extra seating if their edges are wide enough and, if planted appropriately,

Planters soften the wooden flooring of this multi-level, wheelchair accessible deck. A nearby tree provides shade and a ceiling.

a degree of privacy. If near a deck, they help to lower and tie the deck to its landscape. From a xeriscape perspective, however, raised beds lose water much more quickly through drainage and surface and side evaporation than beds at ground level. They need a larger quantity of water applied more frequently. A compromise for a vegetable or herb garden might be to include beds raised no

Design

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more than 10 to 15 cm (4-6 in.) in your plan. Soil is then amendWhat to include in a site analysis

ed downward into the earth to about 45 cm (18 in.).

Visible structures

• house – windows, doors and downspouts • garage – windows, doors and downspouts

• driveway, sidewalks • fence, gates • utility poles (power and telephone), overhead wires

Designing Your Own Xeriscape: From Paper to Reality Step 1: What Is The first step in designing a landscape is to make an inventory of what you have. Sometimes referred to as a "site analysis,"

• satellite dish

it involves using graph paper and a soft pencil and making a

• back lane

plan: drawing to scale the existing features in your yard. One

• garden shed, greenhouse, cold frame,

square may equal 1 m2 (1 yd2). Use the list in the sidebars on

compost pile

this and the following pages to ensure you have included visible

• pool

structures, traffic patterns, hidden structures and plants to be

• dog run • garbage stand • patio, deck, barbecue • outdoor lighting

retained. Make several copies of your base plan. Ensure that your property lines are "real" and not assumed. These include boundaries between your lot and your neighbours’, as well as municipal boulevards, back lanes and public walkways. Once you have made a base plan of visible and hidden structures and plant material to be retained, using tracing paper, do an overlay that emphasizes topography and microclimate. Later, this will help you select plant material that will "fit" each of these areas in terms of sun and shade, soil type, exposure to wind, heat, reflected light, water retention, etc. To do this well, you have to think like a plant, considering various needs. If a part of your property is in full sun and high and dry and windy and sits on gravelly soil, that's what you must write on this overlay: "full sun, high, dry, wind, gravel." Later, you will find a plant that is adaptable to that microclimate. Another planting area may be adjacent to your stucco house, between the foundation and a cement sidewalk and face west or south. You would write: "hot, dry, reflected light and heat." There may be an area under a small

Poplars are fast growing but can be problematic. Their roots are close to the surface and far reaching and may appear where they are not wanted - as in a flower bed or causing a pavement or path to buckle.

22

apple tree that has lovely loam soil with an abundance of organic matter and is shaded. Write: "shade, organic loam." Another area may be shaded but under a poplar with a lot of root competition. Here you would note: "dry shade, root competition." You may wish to supplement the topography and microclimate notes on your overlay of the base plan with photographs of the yard as it is now.

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Step 1: What is Using an older farmyard as an example, visible structures, existing human and vehicle traffic patterns, and plant material to be retained have been noted as well as an analysis of possible use and what needs to be done to accomplish that.

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Step 2: A Wish List How you use your yard will depend largely on the needs and What to include in a site analysis

activities of your household. Make a wish list: what each mem-

Existing human and vehicle traffic patterns

ber of your household wants from the available outdoor space.

Hidden structures

This might include a vegetable garden, barbecue area, play area,

• cable TV and Internet lines, under-

dog run, winter ice rink (situated on the vegetable garden or



ground power lines, gas lines, sewer lines

water catchment area – rinks are very hard on lawns and per-

• irrigation lines

manent plantings), swimming pool, private retreat, pond, tennis

• wells, septic tank

court, bike rack, perennial border, herb garden or whatever.

• any easements associated with above

Your list should also include associated maintenance – a real-

Plant material to be retained

• trees (note height, spread, type of

root system)

istic assessment of the time and work each area or project will involve in the future. Also consider the extent to which you wish to carry out

• shrubs

xeriscape principles. Do you want to make these changes imme-

• flower beds

diately and to your entire yard or slowly and only to portions

• lawns

of your yard? Think about the cost of materials and labour for

• orchard

grading, soil amendments, plants, irrigation, mulch and hard-

• vegetable garden

scape such as decks, walks, fencing or patios.

• shelterbelt • native bush or prairie Overlay with physical features

• north, south, east, west • direction of prevailing winds • slopes, ditches, areas of poor drainage/

water catchment

• areas of permanent shade; hot,

dry areas; areas where snow lingers

Consider which existing elements in your yard will aid you in developing your new landscape. Then prioritize the wish list based on time and budget considerations – and the degree to which your household operates democratically!

Step 3: Function and Use Place tracing paper over the graph paper on which you have drawn the existing features of your yard and the overlay for topography and microclimate. Now is the time to put on paper

• frost pockets

the ideas you came up with during the wish-list phase. Think in

• sheltered areas

terms of function and use, not specific plant material. The task

• areas of root competition

is to make decisions about "screening the neighbour to the east,"

• heat retentive surfaces, areas with

"play area," "good place for moisture-loving plants," or "potential



reflective light

• soil type – texture, pH, salinity,

organic matter, hardpan

pond site," not "I want a lilac here." Use the Checklist for Change in the sidebar on page 31 as a guide. Consider features of your present landscape that will help you in developing your future landscape. Can you utilize an existing Manitoba maple or willow for a tree house with a slide descending into a sandbox? Think of your landscape through the different seasons of the year. What aspects of the winter landscape, for example, when deciduous trees have dropped their leaves, the winds blow and the snow drifts, do you want to modify? Think about sun/shade and microclimate at the time of day when you are most likely outside and enjoying your yard.

24

Creating the Prairie Xeriscape

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Step 4: Filling in the details Here is a generalized plan of the front public area of the farmyard with problem solving underway. The locations and general types of plants have been determined, but the genus, species and cultivars have yet to be decided.

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Step 4: Filling in the details This drawing shows plantings by the house and the garage, and the arbor linking the public and private areas.

26

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Step 4: Filling in the details A generalized plan of the private area of the farmyard with problem solving well underway. The locations and general types of plants have been determined, but with a few exceptions, the genus, species and cultivars have yet to be decided.

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Step 4: Filling in the details One of the more difficult problems in this landscape, was separating the farmyard (both for esthetic and safety reasons) from the private area. This was achieved by repeating the arbor with clematis and using tough ‘Mancana’ ash with groundcovers below, which still allowed the homeowners to know when anyone entered the yard.

28

Creating the Prairie Xeriscape

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Step 4: Filling in the details Planting plan for a large tree-shrub border on an acerage or farm, showing the types of plants to be used.

Step 4: Filling in the details Detail drawing of a corner planting of trees and shrubs suitable for a larger landscape.

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If you already have an underground irrigation system, determine what modifications, if any, it will require to accommodate your new landscape. Think about soils in your yard that have low water-holding capacity due to texture, lack of organic matter, hardpan or shallow depth. Amending these soils prior to planting will save a great deal on your water bill in future years. Alternatively, use extremely drought-tolerant plants in areas with poor soil. Think about your lawn area. How much of it is currently used as lawn? How much is there by default? What parts of it could be reduced and replaced with drought-tolerant shrubs, ground How much of your lawn is actually used as lawn? How much could be replaced with drought tolerant shrubs, ground covers and flower beds?

covers or flower beds? Determine traffic patterns. How is one area of your yard linked to another? Are these routes safe – well lit? Slippery or icy? Steep? Are they convenient and direct? Are they wide enough?

Slopes and banks lend interest to our landscape, but...

recontoured to direct water towards planting

It is difficult to establish or maintain a lawn on

shrubs and ground covers. Construct terraces

steps can be planted with drought-tolerant

a slope and slopes tend to increase water run-

with materials similar to those used in your

off. If your yard slopes, either plant as the grade

house or the hardscape – walkways, decks and

dictates – placing drought-tolerant plants near

fencing – in other parts of your yard.

the top of the slope and plants with higher mois-

Slopes and banks are also ideal locations

ture requirements at the bottom – or change

for a rock garden. Alternatively, vines such as

the grade. In either case, every effort should be

Virginia creeper or riverbank grape can be used

made to reduce runoff and utilize water.

as ground covers to hold slopes.

Water percolation into the soil can be

At the opposite end of the spectrum to

increased by amending it with generous amounts

slopes are moist areas such as depressions and

of organic matter. Lawn areas on a slope can

low areas, drainage swales or low or natural

be aerated. The slope can be contoured so that

catchment areas, areas where snowdrifts accu-

swales (shallow ditches capable of absorbing

mulate and the leeward side of shelterbelts

and/or directing water to catchment areas) cross

where snow is trapped, providing insulation in

horizontally at several points in midslope. Create

winter and added moisture in spring. Identify,

bowl-shaped depressions around plantings on

enhance and utilize areas that may already

the slope. Exposed soil on the slope should be

catch water for plants with high moisture

covered with an organic mulch.

requirements. With minor grading, they may be

As an alternative, the entire slope can be

30

areas. Terraces resembling a series of broad

ideal sites for a pond or bog garden.

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Step 4: Filling In the Details The final step in your plan, also on paper, involves filling in the

Checklist for change

details. To select plant material, you need to do your homework

Views to include:

(see the plant descriptions in Part 2 of this book), but it's also the

• park

most enjoyable and probably the most satisfying part of landscape design. For example, you've already decided that you want a mixed border on the west side of your yard that will give you shade from the late afternoon sun and be visually pleasing. Now you decide exactly what that border will consist of. Each area of your yard will need "walls," a "ceiling" and "floor-

• neighbour’s trees or shrubs • river, lake • hill Views to exclude:

• neighbouring buildings, old granary,

neighbour’s garage

• utility poles

ing" in much the same way as the rooms of your house. These

• roads or highways

can be of plant or non-plant material or a combination of both.

Modifying your environment:

Garden Walls

• where is protection from prevailing wind,

noise, glare or dust needed?

Walls are the vertical dimension of your yard and may be in the

• where is screening for privacy needed?

form of trees, shrubs, hedges, vines, fencing, trellises or tradi-

• where is shade needed – patio, deck,

tional walls of stone or brick. They function to ensure privacy;



increase your comfort by reducing dust, wind, noise and glare;

• where should soil be amended?

provide a pleasing backdrop for other plantings; and mark prop-

Problem areas that might need change:

erty boundaries. They enclose and define not only the yard as

• steep slopes – terracing, rock garden

a whole, but the areas within it. To do this, the material used

• poorly drained area – water catchment

should be fairly tall (1.5–2 m/5–6 ft) and – especially on smaller lots – take up as little width as possible. Hedges

Hedges are trees or shrubs, selected for their density, which are planted in straight lines and usually require one or more annual shearings. Their initial cost is low, but it takes five or six years to form a good hedge. During this period, they must be trained through shearing. A hedge takes up more space than a wall or fence – something to be considered on a smaller lot – and involves a high degree of maintenance. If you opt for a hedge, select hedging plants that are extremely drought tolerant, such as lilac, cotoneaster or caragana. Shrubs



play area, dog run?

area/pond

Possible locations of specific use areas:

• patio or deck – shaded, convenient to

living room, kitchen?

• vegetable garden – minimum of six

hours of sun, available water, accessible to rototiller, manure loads?

• play area – visible from window, shaded,

safe from street?

• lawn area – size suitable to household

needs, adjacent to deck or patio, partially shaded?

• dog run – shaded, hard surface? • pool – sunny; tennis court – shaded? • greenhouse/cold frames, minimum of six

hours of sun?

Shrubs may also form the walls of a yard. Shrubs occupy more

• utility areas, compost near garden,

space than hedges, but they need less maintenance and are far



more interesting, much less labour intensive and an invitation

Human and vehicle traffic patterns:

to birds to take up residence. If left untrimmed, in their natu-

• driveway – convenient, space conserving?

ral shape, they should form informal groupings rather than be

• walkway to front entry

planted in an evenly spaced straight line. Select several species

• front yard to backyard

for year-round interest, considering mature height and width,

• rear entrance of house to: back lane,

site requirements, disease and insect resistance, fruit, flow-



garbage screened, clothesline?

garbage, garage, garden, tool shed

ers, bark colour and texture, leaf texture and seasonal colour changes. Ensure they are hardy and drought tolerant.

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Trees Planting ideas for a mixed layered border

The number of drought-tolerant trees now available to prairie

Trees

scapes and should be chosen with care. It is critical to know the

Basswood, ‘Thunderchild’ or ‘Spring Snow’ flowering crabapple, subalpine fir, ‘Delta’ hackberry, bur oak

Taller shrubs Cotoneaster, honeysuckle, ‘Meyer’ lilac, ninebark, ‘Northline’ saskatoon berry, variegated wayfaring tree

Shorter shrubs Barberry, ‘Effusa’ juniper, ‘Slowmound’ mugo pine, potentilla, shrub roses, nest spruce

gardeners is truly amazing. Trees form the bones of our landmature height and spread of the trees you select, so base your initial options on size, using the reference charts in the appendix of this book. Then read the detailed entries in Part 2 to make your final selections. Choose species that are long-lived and have year-round landscape value. A 'Toba' hawthorn is a good choice to shade a small patio; a Manitoba maple is better suited to a larger rural yard. Do not plant Siberian (or Manchurian) elms or large poplars on small urban lots. Although their fast growth is widely publicized, they are short lived and expensive to remove. Siberian elms self-seed generously and poplars sucker readily. Both have

Perennials Artemisia ‘Silver Brocade,’ basket-of-gold alyssum, bergenia, blue fescue ornamental grass, coral bells, daylily, gaillardia, iris, lily, peony, pinks, oriental poppy, rockcress, snow-in-summer, yucca

weak limbs prone to wind and storm damage and are susceptible to insect infestation and disease. And both are very competitive for moisture with other plants within their root zones. Better trees are available! Avoid planting trees with large, spreading or shallow root systems – poplar, Manitoba maple, elm and spruce – near gar-

Annuals: Beggar’s tick (tickseed), calendula, cornflower, cosmos, dianthus, dusty miller, gaillardia, globe amaranth, marigold, petunia, California poppy, portulaca, clary sage, vinca, zinnia, creeping zinnia

dens, swimming pools, walks, driveways, house foundations, septic systems and sewer lines. Columnar trees such as upright juniper are a good choice for screening, especially between properties on smaller urban lots. Spruce and pine can be used to screen for privacy, provide a barrier and act as a background planting through the entire year if your lot is large enough to accommodate them. They will deflect prevailing winds if placed on the north and west of the house and yard. They act as a snow fence, so plant them far enough from walks and buildings to prevent snow accumulation on driveways or walks. Vines

Vines may be used to hide unsightly buildings or soften and break up an otherwise solid expanse of wall or fence. They can disguise guy wires and hide power and telephone poles. Most vines will need some sort of support and are usually used in combination with a wall, fence, trellis or arbor (or even allowed to drape over a dead tree). When selecting vines, consider the type of support they will need – do they have tendrils that will Vines over a gate arouse curiosity and invite the visitor to enter to see what may lie beyond.

32

need something to wind around or do they have holdfasts which will cling to brick but may damage painted surfaces?

Creating the Prairie Xeriscape

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Fencing

From a xeriscape point of view, a fence may need repainting, but never watering and that makes it an excellent choice. Another advantage of fencing is its narrow spatial requirement – a few centimetres compared to a metre for hedges or a few metres for shrubs and trees. This is an important consideration on smaller urban lots. Other advantages include the "instant" quality of its installation and its relative permanency. Its disadvantages are its initial expense and periodic maintenance. Masonry walls

Walls are traditionally constructed of brick or stone. Choose a material that has already been used on your house or in your landscape for walkways or patio flooring. Walls require skill to build but are relatively permanent. Aesthetically, they lend an Old World charm to your landscape, giving privacy and wind protection and creating a favourable microclimate for plants with borderline hardiness.

Garden Ceilings Garden ceilings provide shade, shelter and the beauty of colour and texture. Trees, vines, roof overhangs, awnings, pergolas and trellises may all be used to advantage. Trees

Stone walls lend permanency and Old World charm to our gardens. They also provide a home to extremely drought tolerant plants such as hens and chicks.

When deciding on the placement of shade trees, think of where you want shade and the direction of the sun at the time of day you'll most likely be using that area. Use deciduous trees to provide shade for patios, decks or the south- and west-facing sides of a house. There, they provide shade and cooler temperatures during the heat of summer, but allow the warmth of the sun to penetrate during winter and early spring when their boughs are bare. A deck or patio may be constructed to include an existing tree or a space may be left so that a young tree of fairly small mature size may be planted. Your design should allow for the expanding trunk diameter of the tree as well as its water requirements. Interlocking bricks are easily removed as the growth of the trunk requires. Avoid selecting "messy" shade trees or nuisance trees near patios or decks. Among these are Manitoba maples (honeydew from aphids, twig and seed drop), elms (aphids, cankerworms, self-seeding), willows ("self-prune" during strong winds), poplars and cottonwoods (seed, sucker, drop twigs and sometimes "fluff") and large-fruited crabapples that drop their fruit in fall rather than retaining it through the winter. ('Spring Snow' is a

As Robert Frost once wrote, “Good fences make good neighbors.” They provide privacy while taking up minimal space. And they need not look like stockades. This one exudes warmth, craftsmanship and excellent design.

sterile flowering crabapple that develops no fruit.)

Design

Ch2_Design_Final.indd 33

33

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Grouping by Water Needs Using your site analysis, divide your yard into

Group these in the following areas:

separate areas for plants with low, moderate and high water needs. Use the most drought-tolerant plants (indicated by the icon

G

• areas with moisture-retentive soils

in the following areas:

• purposely contoured water catchment

• southern or western exposures

areas

• areas with the least water-retentive soil

• northern or eastern exposures

(soil that is sandy or lacks organic

matter)

• areas that are shaded or partially shaded

• areas with reflected light (from

white or aluminum siding, stucco or a



white fence), especially from south- or



west-facing structures • near heat-retentive surfaces (asphalt



quantities of organic matter) • areas of lower elevation

• areas with higher elevation



(clay, loam or soil containing generous

or concrete)



established trees • areas where snow accumulates in



winter and melts slowly in spring or



where water lingers after a heavy



• on slopes

and sheltered from prevailing winds • areas with no root competition from

rain or irrigation. This grouping of plants with higher water

• in the path of prevailing winds

needs is relatively small and is situated as close

• on the perimeter of rural properties

to the house as possible to make watering easi-

• near mature trees with competitive roots

er and more convenient.

• in full sun

Use plants that are moderately drought tol-

Extremely drought-tolerant plants in these

erant between these two extremes. Moderately

areas will need irrigation during establishment,

drought-tolerant plants (also listed in Part 2

G icon) will need supplemental

but will later require little if any supplemental

but without

water.

water during establishment and extended hot,

At the opposite extreme are plants with high water needs, including willow, birch, prim-

dry periods. Direct water from catchment areas towards beds containing these plants.

rose, tea rose, hosta and strawberry.

This formal succulent garden is composed of extremely droughttolerant plants.

34

Moderately drought-tolerant plants make up this informal pink border.

These plants will need much more water than natural precipitation can provide.

Creating the Prairie Xeriscape

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Trellises, arbors, pergolas and roof overhangs

These types of garden ceilings are usually draped with vines. They provide summer shade yet do not interfere with air circulation beneath. Grape, Virginia creeper, clematis and honeysuckle allow the spring and early summer sun to warm a deck or patio while still providing shade and cooler temperatures during the heat of summer.

Garden Flooring Flooring for outdoor use in the landscape can be of plant and non-plant materials. While grass is the most common flooring in conventional landscapes, in a xeriscape design much of our lawn is replaced with drought-tolerant ground covers and, in intensively used areas, with non-plant material. There is extensive use of decks and patios, which may require some upkeep on your part, but never water! Hard surfaces

Non-plant materials commonly used as flooring in the landscape include wood for decks, crushed stone, slate or gravel for

The bricks in this walk reflect the bricks of which the house is constructed, thereby unifying house and garden. Bellflowers lend charm while softening the hardscape.

informal paths and natural stone, brick, concrete block, poured concrete and interlocking concrete or clay brick for patios, walkways and driveways. Select materials that reflect the materials used in your house as well as the formality or informality of your landscape. Avoid hard surfaces that reflect light or absorb an undue amount of heat. Lawns

Lawns are pleasant to look at, resilient, comfortable to sit and walk on and safe for children. But they require more water than almost any other part of the landscape and are often planted much more extensively than their use dictates. In xeriscape designs, lawns are reduced to the area that is actually used as a lawn (rather than an expanse of green turf that is only looked at), shaped to conform to the delivery pattern of the sprinkler used to irrigate them and cared for just a bit differently than conventional lawns, all in an effort to conserve water. (See chapter 6.) Ground covers

Ground covers include low evergreen or deciduous shrubs, ornamental grasses, vines and perennials. They are useful

This slate path winds its way through an informal woodland garden.

where lawns are not practical, where a different colour, texture or height is desired or where a lower type of continuous plant material is needed to unify several trees and shrubs within a planting. In a xeriscape design, ground covers are chosen for their drought tolerance.

Design

Ch2_Design_Final.indd 35

35

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Low junipers and sedums are useful on terraces or steep slopes where lawns would be difficult to establish and maintain and would be wasteful of water. More aggressive plants such as Waldsteinia, windflower or bigfoot geranium excel in these situations. Although we think of vines as vertical, Virginia creeper and Manitoba grape are also useful horizontally and make excellent ground covers, especially on slopes or banks. Bergenia, creeping juniper and dwarf veronicas can unify tree-shrub borders while simultaneously preventing weed establishment and controlling erosion. When planted around a specimen tree or group of trees (such as daylilies at the base of a bur oak or bergenias under a flowering crabapple tree), ground covers tend to emphasize that tree or grouping as a focal point. Thyme, dwarf veronica, smaller sedums and other flowering alpine or rockery plants may be used as "pavement plantings" on the edge of and among paving stones, interlocking bricks, patio blocks or conventional bricks to soften and add colour to an Lambs ears is an ideal ground cover for a hot, dry area. The woolly texture has great appeal to all ages while the silver grey fits almost any colour scheme.

otherwise large expanse of hard surface forming a patio, walk, driveway or garden stairway. Do not plant them in the direct line of traffic, as they will not tolerate being trampled. Mulches

Organic mulches used to cover the soil surface in planting beds (see chapter 5) also constitute flooring material and in many instances serve a design function. They provide colour and texture, unify a large planting bed, especially when the plant material is still young and small. In a subtle way, they announce that this area has indeed been landscaped and would be better walked around than across! In beds with smaller plants or plants of low stature, use finer mulches or top-dress coarse mulching materials with coarse peat moss. Where plants are larger, coarser mulches may be applied. Mulches such as wood chips and post peelings can be used for informal paths and walkways.

Dirt is what's tracked onto your kitchen floor. Soil is Although we normally think of Virginia creeper in a vertical sense as a vine, it is also very useful on a horizontal plane as a ground cover on a slope or bank or other difficult situation.

36

what plants grow in.

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CHAPTER 3

Soil From the Ground Up Soil is basic to the concept of xeriscape. The quality of your soil makes a big difference to the health of your plants and how often you need to water. And high quality soil gives you more choices in the plants you can grow: rather than being restricted to those plants to which your soil is suited, you can change the soil and grow the plants you want to grow. We tend to take soil for granted, but more plant problems are related to soil than any other factor. All too often, we would rather look for a quick fix, like a pesticide or synthetic fertilizer, than deal with the soil itself. However, it is better to start from the ground up and ensure that the soil you work with has the capacity to supply plants with the oxygen, water and nutrients they need. Incorporating soil amendments solves many problems, enormously increasing the workability and productivity of your soil. Soil is important. It provides mechanical or physical support for plants – quite simply, a medium in which they can grow. Soil water is required for the hundreds of biochemical reactions that take place within a plant; it prevents them from wilting and provides them with nutrients and a cooling system.

What Is Soil? Soil forms a relatively shallow layer on the earth’s surface. It is dynamic. It has changed over the millennia since its formation and to a lesser degree over the past few days. These changes may involve moisture, temperature, organic matter content, microorganisms or nutrient levels and they often affect how well plants grow.

Incorporating organic matter into your soil increases its workability and productivity enormously. It’s much easier to do this before you plant than after the fact. But digging in organic matter to an established bed is well worth the effort.

Soil

37

Rock, Organic Matter, Water and Air Contrary to its appearance, only 50 percent of soil is solid. Most of this is formed from rock that has been worn down, broken up and eroded to form smaller and smaller particles of various sizes. A very small percentage, about 5 percent, of prairie soil is made up of organic matter, which is or was alive. It is mostly composed of decayed vegetation contributed by the roots of native grasses. Organic matter gives soil much of its ability to absorb and hold water along with the nutrients that are dissolved in the soil water. It improves the tilth (workability) of the soil and provides a slow release of nutrients. It also helps to maintain the pore structure of the soil – the spaces in between the solid soil Prairie soils contain about five percent organic matter. It developed over many centuries from the slowly decaying roots of the native perennial grasses that once covered the central and southern prairie landscape.

particles. The higher the organic matter content, the greater the soil’s ability to hold and store water and nutrients. Of the remaining 50 percent of the soil’s volume, ideally 25 percent is water and 25 percent is air. The soil atmosphere, located in the pore spaces surrounding the solid particles, is variable, but generally consists of 20 percent oxygen, 79 percent nitrogen and 1 percent carbon dioxide. All plant cells, including those of the roots, need oxygen. When soils are waterlogged and water fills the pore space, oxygen is unavailable and plants suffer. The relationship of air, water, soil and plants is discussed in chapter 4.

Soil Texture: Sand, Silt and Clay Soil texture refers to the relative proportion of sand, silt and clay in a given soil. The rock or mineral portion of soil is described in terms of the size of these individual particles. A loam soil has almost equal proportions of sand, silt and clay. It is the best for gardening because of its ease of workability. Sand has the largest particles (0.05 to 2.0 mm in diameter). They are visible to the naked eye, irregular in shape and gritty to the touch when wetted. A sandy soil drains easily and quickly after rain or irrigation, is easily worked and warms up quickly in the spring, but it has a very low moisture-holding capacity and must be watered frequently. It also has a low nutrient-holding capacity and must be fertilized more often than a clay soil. Sandy soils have a low moisture and nutrient holding capacity and should be well amended with organic matter. They are easily worked and warm up quickly in the spring.

38

Creating the Prairie Xeriscape

When vegetative cover or mulch is lacking, it is subject to wind and water erosion. Silt particles are intermediate in size (0.002 to 0.05 mm in diameter). They are irregular in shape and visible only with the aid of a microscope. Silt particles feel smooth and slippery to the touch when wetted.

Clay particles are the smallest of all (less than 0.002 mm in diameter) and are only visible with the aid of an electron microscope. Clay particles attract water as well as nutrients such as calcium, magnesium and potassium. When wet, clay is sticky to the touch. Clay soils hold large amounts of water and nutrients, but are often poorly drained. They warm up more slowly in the spring, which means a delay of a week or two in planting, shortening an already limited growing season. Because of their large water-holding capacity, they expand and contract with alternate freezing and thawing in spring and fall, causing root damage and heaving of plants out of the soil. Crusting and cracking are also common problems in clay soils. Crusting impedes water percolation and seedling emergence and encourages runoff. Cracking damages and dries out roots. Clay soils are often difficult to work. If too wet, they are gummy and impossible. If too dry, they can be similar to concrete.

Problems with Soil

Clay soils hold large amounts of water and nutrients but are poorly drained, can be difficult to work, and have a tendency to crust and crack. Amend them with equal volumes of large grained coarse sand and organic matter.

Besides being too sandy or too clay-like, soils may have poor structure or problems associated with pH or salt. Plants grow poorly on soils that lack aeration or adequate drainage, are unable to hold water or nutrients, are overly acidic or alkaline or are saline.

Hardpans Hardpans are compacted layers usually less than a metre (3 ft) below the soil surface. They make root penetration and water percolation more difficult and usually contribute to poor drainage and aeration. If the hardpan is immediately below the soil surface, the effective soil depth is limited, resulting in poor plant growth. Compaction problems are often the result of repeated use of heavy machinery on wet soils. Compaction destroys the structure of soil particles, reducing the pore space capable of holding air and water. Improving these soils requires digging below the hardpan, breaking it up and thoroughly incorporating generous amounts of organic matter. Alternatively, raised or bermed beds containing amended soil may be constructed above the hardpans. This is

Construct bermed or raised beds, well amended with organic matter, above hard pan, poorly drained or saline soils.

often an easy and effective alternative, but it is not conserving of water. The higher a bed is raised, the greater the amount of water lost to evaporation.

Soil

39

Very salt-tolerant trees and shrubs

• bearberry (Arctostaphylos uva-ursi) • buffaloberry (Shepherdia argentea) • cockspur hawthorn (Crataegus

pH pH is a measure of the acidity or alkalinity of a soil, measured on a scale of 0 to 14, with 0 being the acidic end of the scale, 7 neutral and 14 the alkaline (or basic) end. The pH scale is loga-

crus-galli)

rithmic rather than geometric: A pH of 6 is 10 times more acidic

• false indigo (Amorpha fruticosa)

than a pH of 7. A pH of 5 is 100 times more acidic than a pH of 7.

• Japanese barberry (Berberis thunbergii)

pH is important because it indicates availability of nutrients.

• late lilac (Syringa villosa)

At a neutral pH (7), most nutrients in the soil water are in a

• Russian olive (Elaeagnus angustifolia)

soluble form and can be absorbed and used by plants. Soil bac-

• sagebrush (Artemisia spp.)

teria and fungi are also active in this range. A pH of 6 to 7.5

• salt tree (Halimodendron halodendron)

is considered ideal for gardening and horticulture. As the pH

• sea buckthorn (Hippophae rhamnoides) • smooth sumac (Rhus glabra) • snowberry (Symphoricarpos spp.) • Ural false spirea (Sorbaria sorbifolia)

moves further away from this range, some nutrients become less soluble in the soil water and thus less available for plant use. Bacterial activity, important to the availability of nitrogen and other nutrients, is also reduced. Most southern and central prairie soils are basic or alkaline

Moderately salt-tolerant trees and shrubs

(with a pH greater than 7). This means that iron, an essential

• caragana (Caragana spp.)

trace element, although present in the soil, is often tied up in

• chokecherry (Prunus virginiana var.

an insoluble form and unavailable for plant use. This results in

melanocarpa)

chlorosis. At a pH much above 8, phosphorus, manganese, zinc,

• green ash (Fraxinus pennsylvanica

copper, cobalt and boron may also be unavailable.



var. subintegerrima)

• Manitoba maple (Acer negundo) • Rocky Mountain juniper

A prevalent urban myth is that our northern forest soils are acidic because of the acid pine and spruce needles that fall on

(Juniperus scopulorum)

the soil. This is untrue. The pH of a soil is largely determined by

• Tartarian honeysuckle (Lonicera tatarica)

the rock from which it originated, not the forest trees that grow

• wolfwillow (Elaeagnus commutata)

there. Northern forest soils tend to be slightly acidic. Although most plants grow well at a neutral pH, blueberries and azaleas will only grow in more acidic soils. Although possible, it is difficult to permanently raise or lower the pH of soils and it is generally unnecessary. However, if you have your soil tested, and the pH is below 6.0 or above 7.5, the soil testing laboratory may recommend that you try to change it. Lime is used to raise the pH of acidic soils; elemental sulfur, peat moss and organic matter are used to lower the pH of alkaline soils. Apply these in accordance with recommendations from the laboratory based on the results of a soil test. Even if our prairie soil is generously amended with peat moss, however, eventually the pH rises due to the alkalinity of rain and the surrounding soil.

Salinity Chlorosis, indicated by a yellow leaf blade and green veins, signals an iron deficiency due to high soil pH.

40

Creating the Prairie Xeriscape

Salinity is the measure of salts within a soil. It often occurs where the water table is relatively close to the soil surface. Salts are wicked to the surface through evaporation and capillary

action during the summer, when the evaporation rate is often greater than the precipitation rate. Over time, these salts accumulate and plant growth is adversely affected. Saline soils are bad for plant growth because instead of water moving from the soil into the plant, water is pulled from the relatively pure solution within the plant into the more concentrated solution of the saline soil water. Bathing in the Dead Sea or a mineral spa would do the same thing to our skin – dry it out! As water is pulled out of the plant, the plant wilts and dies. A white soil surface indicates the presence of salts. A soil test will tell you how bad it is. Saline soils can be improved by providing better drainage, deep watering and incorporating generous amounts of well-rotted organic material. Adding fresh manures with ammonia salts will make them worse.

Making Soil Better Soil amendments are generally organic materials such as compost, peat moss and composted manures that are added to the soil to improve its productivity. They do this by improving its

Saline soils, generally with an obvious white appearance, contain salts that hinder plant growth. For a list of salt-tolerant plants, see page 40.

aeration, drainage, nutrient- and water-holding capacity and tilth (workability). They may be added to large planting beds or individual planting holes, depending on their cost, availability, the plant material and the existing soil.

Amending planting holes

Always thoroughly incorporate amendments into the exist-

It is often more efficient and economical

ing soil. Never leave them as a surface layer. When soils of

to amend only the planting holes of trees

different textures are layered, water movement from one layer

and shrubs rather than an entire bed. Sandy

to the next is impeded. This leads to saturation of the upper lay-

soils will usually benefit from the addition

er and sideways rather than downward movement of the water before the second layer is wetted. Root penetration is often hindered, leading to shallow root development, leaving plants more vulnerable to cold, heat and drought. Thorough incorporation of soil amendments – so that a gradation exists from the amended

of organic matter to planting holes and clay soils from a mixture of organic matter and very coarse sand. Some studies have shown adding organic matter to planting holes in heavy clay causes too much water to be held by the

topsoil to the subsoil – encourages water percolation and root

amendment, and the roots lack oxygen.

development into the lower soil depths.

Once the amendments dry out, they are

If large quantities of amendment are to be added to a plant-

difficult to rewet. Roots do not move out

ing bed or vegetable garden, it may be beneficial to spread a 5

into the poorer surrounding soil, thus re-

to 7.5 cm (2–3 in.) layer, thoroughly incorporate it by tilling, then

ducing the soil volume from which they can

add another layer and perhaps even a third, rather than adding

absorb water and nutrients. If amendments

all of the amendment at once.

in a planting hole are thoroughly incorporated with the existing soil, however, both

Organic Amendments All organic soil amendments will eventually break down through microbial action. When conditions are consistently

in depth and laterally, these problems will not be as great. Alternatively, entire beds may be amended.

Soil

41

warm and moist, this happens quickly. Under dry prairie condiSynthetic versus organic fertilizers

tions and our limited growing season, the process is relatively

A fertilizer supplies nutrients (such as nitro-

slow. Organic matter breaks down sooner if the soil is frequently

gen, phosphorus and potassium) essential

tilled. Mulching is a better option in permanent plantings. It

for plant growth. Synthetic fertilizers are

allows a slower decomposition of organic matter accompanied

usually less expensive than organic fertil-

by a slower release of nutrients. As organic matter breaks down,

izers. They are water-soluble, have a predictable rate of release and are consistent in the percentage of nutrients they contain. Unfortunately, although they add nutrients to the soil, they do not improve its texture

it releases nutrients. It also improves the physical structure of the soil, its aeration and water- and nutrient-holding abilities. It is relatively easy to document nutrients released by organic matter. It is more difficult to place an economic value

or structure. Their solubility can lead to inef-

on improved soil structure, so as significant as this may be in

ficient use, leaching below the root zones of

the life of a gardener, its value is often underrated and ignored.

plants and contamination of groundwater. In

Bacteria and fungi play a critical role in decomposition and

a prairie xeriscape, it is better to use organic

disease control. The more diverse the microbial population, the

fertilizers.

less likely is the uncontrolled spread of a single harmful microbe.

Organic fertilizers are less concentrated

Some beneficial microbes are able to “fix” atmospheric nitrogen

than synthetic ones. They are held in a non-

in a form usable by plants. Others stimulate plant growth by

leachable form that is released slowly into

secreting hormones.

the soil. They require microbial activity for release, generally when temperatures are above 10°C (50°F). They are generally more costly per unit of nutrient, more bulky and their precise analysis is not known. However, they do things that inorganic fertilizers are

What does this have to do with a soil’s water- and nutrient-holding ability? Organic matter supplies both habitat and nutrients for microorganisms and thus increases the level of microbial or biological activity. As organic matter decomposes, it forms humus, which holds potassium, calcium, magnesium and

not able to: stimulate microbial activity, im-

hydrogen in the soil water in a form that is readily available to

prove soil structure, increase the water- and

plants but is not easily leached. Because humus attracts water

nutrient-holding ability of the soil and im-

molecules, a soil’s water-holding capacity is also increased.

prove its porosity. Plus, they are renewable.

Organic matter can hold almost twice as much water as clay. The addition of organic matter to sandy soils can dramatically improve nutrient availability and reduce nutrient leaching. Compost

Compost is living material on its way to becoming humus: the dark, crumbly, sweet-smelling stuff that is the result of decomposition. Composting recycles waste organic materials from your landscape by speeding up what normally occurs in nature by providing the ideal conditions in terms of oxygen and water. The end product is an excellent soil conditioner and slow-release fertilizer that would otherwise be lost forever to garbage dumps and landfills. The soil microorganisms that decompose the raw materials require oxygen, water and a balance of nitrogen (“green stuff” Composting recycles organic waste into an excellent soil conditioner and slow-release fertilizer.

42

Creating the Prairie Xeriscape

such as grass clippings, fresh kitchen waste and garden refuse) and carbon (“yellow stuff” such as dry grass, leaves and straw). Although commercial inoculants are available, soil and the

materials that go into the compost pile usually contain enough microorganisms, so a few shovelsful of soil will usually suffice. There are various methods of composting. Sheet composting involves spreading out the raw materials on the soil surface and incorporating them with a spade or a tiller. This is best done in

What to compost

• kitchen scraps such as fruit, vegetables,

tea bags, coffee grounds, eggshells

the fall on a vegetable garden area. In trench composting, dig a

• leaves

trench 45 cm (18 in.) deep and the same width in a garden area

• grass clippings

and fill it with kitchen scraps or grass clippings as they become

• garden refuse without seed heads

available and then cover it with soil. Rotate the location of the

• livestock manures

trench itself from season to season. Compost piles are a more concentrated method of composting. The finished product can be used anywhere in the landscape. Urban residents are more likely to use bins because of concerns about aesthetics and space. Many building plans are available

What not to compost

• meat and bones • weeds that have gone to seed • cat, dog, pig and human feces • diseased garden refuse

as well as ready-made commercial composters. Of course, compost may simply be put in a pile. The minimum effective size is 1 m3 (1 yd3). Smaller piles are prone to moisture and heat loss. Layer the contents of a pile or bin 10 to 20 cm (4–8 in.) deep, alternating high-carbon materials and high-nitrogen materials with a few centimetres (approximately an inch) of soil in between. Add enough water to keep the pile moist but not waterlogged. Turn the pile with a long-tined garden fork so that oxygen is present. If organic materials decay without oxygen (anaerobic decomposition), they will smell much like silage. With the right mixture of ingredients and enough volume, compost should heat to 70°C (160°F), hot enough to kill most weed seeds and decompose raw materials. On the prairies, it generally takes a full growing season to yield usable compost, but this depends on the materials used, their size (smaller particles decompose more quickly), the moisture and oxygen content of the pile and ambient temperature. Manures and Other Animal By-products

Organic fertilizers – for the most part farm animal manure – hold nutrients in a less leachable form than inorganic chemical fertilizers and release them more slowly. Manures may not be readily available in urban areas and are labour-intensive to spread. Their nitrogen content decreases with age, exposure to wind and rain and the degree of microbial activity present. Much is lost by leaching and volatilization (evaporation into the air). Bedding and litter mixed with manures

Composted animal manures are a great source of organic matter. As well, they hold nutrients in a less leachable form than inorganic chemical fertilizers, releasing them slowly into the soil.

lower the percentage of nitrogen but increase the amount of organic matter. If immediately incorporated into a vegetable garden or planting bed in the fall, nitrogen loss is reduced.

Soil

43

Fresh manure is high in ammonia and salts and will “burn” Making sense of manures and meals

or desiccate plants. It should be aged or composted for at least

The chart below shows the average percent-

a year. Composting allows the ammonia to volatilize into the

age of available nitrogen (N), phosphorus (P) and potassium (K) in animal manures and by-products.

air, salts to be leached out by rain and weed seeds to heat to the point where hopefully they may no longer be viable. Manures vary in their nutrient content depending on the

Product

N P K

fresh cow manure with bedding

0.5

0.3

0.5

dried poultry manure

4.0

3.0

3.0

dried rabbit manure

2.4

0.6

.05

fresh sheep manure

1.0

0.4

0.2

by-products of the slaughterhouse. They contain a higher

fresh horse manure

0.4

0.2

0.4

concentration of nutrients (including trace elements) but less

blood meal

10-15

1.3

0.7

organic matter than many other amendments mentioned. Blood

bone meal

2-4

22-24 0.2

meal and hoof and horn meal contain quick-release forms of

hoof and horn meal

10-14

1-2

0.0

nitrogen; bone meal has a slowly released form of phosphorus.

alfalfa pellets/meal

3.0

1.0

2.0

These products are relatively expensive and not always avail-

corn gluten meal

9-10

0.0

0.0

able, as many have been diverted into animal feeds.

type of animal, what it’s been eating and the age and storage conditions of the manure. Commercially dried manures are more costly than bulk manures. Blood meal, bone meal and hoof and horn meal are all

Peat Moss

Peat moss improves soil aeration, increases its ability to hold nutrients and water and adds organic matter to the soil. It Peat moss potential

decomposes at a moderate rate, but the coarser the material, the

The leaves and stems of sphagnum, from

slower the decomposition. Peat moss is very low in nutrient val-

which peat moss is derived, consist of a

ue, containing up to 3 percent nitrogen but few other nutrients.

single layer of large cells capable of holding 10 to 15 times their weight in water, a characteristic retained even when harvested, dried and pressed into bales. As well, it contains a compound called shagnol, which has mildly antiseptic properties and was

Its pH is between 3.0 and 4.5, making it useful for acid-loving plants such as azaleas and blueberries and for lowering the pH of alkaline soils. It is a consistent and lightweight product, but large quantities can be expensive. Moisten it prior to use. Leaf Mold

used until World War I as a wound dressing.

Leaf mold is a valuable soil amendment consisting mainly of

Peat moss was first used for horticultural

decayed leaves, which all too often we bag and send to the

purposes only a century ago. Thirty percent

dump. Leaves may be mowed with a lawn mower in the fall and

of the world’s supply is in Canada.

immediately spread and incorporated into a vegetable garden or annual flower bed, piled separately for later use or added to a compost pile. Mushroom Compost

This is the material that remains after mushrooms have been harvested. It generally begins as a mixture of animal manures and straw and has usually been heated enough to kill any soil organisms that would compete with the mushroom themselves. It has a low level of nutrients but is an excellent soil conditioner. It may contain salts. Wood Products: Sawdust, Chips and Ash

Sawdust and wood shavings may be added to clay soils to

44

Creating the Prairie Xeriscape

improve aeration and to sandy soils to increase their water- and nutrient-holding abilities. These products and ash are of interest if you happen to garden near a sawmill, do a lot of woodworking or heat with a woodstove. They are valuable amendments in moderation, but don’t overdo them. If used in large quantities (over 10 kg per 100 m2/20 lb per 1,000 ft2), they may raise the pH

Myth and reality: Nitrogen depletion, toxicity and acidity Wood products suffer from bad publicity regarding their effects on nitrogen, their toxicity to other plants and their “acid” nature. Wood shavings decompose slowly due

of the soil to which they are applied. Do not apply them near

to their high carbon and lignin content and

acid-loving plants such as azaleas or blueberries. Avoid direct

generally do not tie up nitrogen. Sawdust

contact with young plants and germinating seeds.

decomposes fairly rapidly and may tem-

Per tonne (ton), sawdust contains about 1.8 kg (4 lb) of nitro-

porarily tie up soil nitrogen. Sawdust of

gen, 0.9 kg (2 lb) of phosphorus, 1.8 kg (4 lb) of potassium, 2.7 kg

deciduous trees decomposes more quickly

(6 lb) of calcium and 0.2 kg (0.5 lb) of magnesium. Wood ash is

and is more likely to be a problem than that

25 percent calcium, 5 to 10 percent potassium and 1 to 2 percent

of coniferous trees. To be on the safe side,

phosphorus by weight, plus trace elements.

compost it before adding it to the soil.

Green Manures

Green manures, sometimes called cover crops, are seeded in summer and turned under once mature (but prior to seed formation) in late fall or spring of the following year. If left over

Monitor plants for signs of nitrogen deficiency when using wood amendments. Look for overall pale green or yellow foliage, especially on older growth. Except for a few species, none of which

winter, they protect the soil and trap snow. When incorporated,

are grown on the prairies, toxicity is not

they add nutrients and organic matter to soil. They are usually

considered a problem. Trees with phyto-

grown a full year prior to the area being planted. They are inex-

toxic properties include: western red cedar,

pensive (the only cost is seed), but take time and labour. Fall rye,

white pine (bark), black walnut, hemlock

alfalfa, sweet clover, oats, peas, lentils, millet and buckwheat

(bark) and redwood. Bark or sawdust from

have been used for this purpose.

green, newly milled trees will be more

Topsoil

If your topsoil is thin, add more. Topsoil is extremely variable from source to source. If you’re investing in a large quantity, obtain a sample and have it tested to determine its texture, the amount of organic material present and its salt content. If it’s an agricultural soil, you can often detect the presence of herbicides by a germination test using fresh pea or bean seeds. If seeds fail to germinate, it may indicate herbicide contamination.

toxic. Allowing these products to leach for six weeks reduces the problem. Toxic substances are usually destroyed by soil bacteria and fungi within a few weeks after the addition of sawdust or shavings to soil. Although most sawdust is slightly acid, it has no harmful effect on soils. Organic acids formed during decomposition break down quickly, and the final effect on soil pH is negligible.

Inorganic Amendments Inorganic soil amendments are added to improve soil texture, aiding aeration and drainage. They must be purchased and hauled, are variable in their durability and usually provide little or no nutrient value. Sand

Use sand in combination with an equal volume of organic material to lighten heavy clay soils. Sand improves drainage by creating larger pores. The sand should be coarse textured (with a particle diameter greater than 0.5 mm) and of irregular shape,

Soil

45

not small, rounded particles. If small, rounded particles of sand are added directly to clay, the resultant soil is similar to concrete. Washed, coarse silica sand (also called builders’ sand) is recommended. Very large quantities of coarse sand and organic matter are required to make a significant change. Experiment with a small area of clay to determine the optimum amount to be incorporated. Perlite and Vermiculite

Perlite is manufactured from a granite-like, volcanic rock, which is first crushed and then heated to 980°C (1800°F), causing its granules to expand and fill with air. It is white, inert, lightweight, Peat moss, capable of holding ten times its weight in water, is derived from the leaves and stems of Sphagnum species, plants native to our boreal forests.

has a neutral pH and holds few nutrients. It’s used indoors and in greenhouses in soilless media to increase soil aeration and drainage. Vermiculite is made by heating particles of raw mica to 870°C (1600°F), expanding them up to twelve times their normal volume. Like perlite, it is inert, lightweight and consistent and is used extensively indoors in soilless media to increase their ability to absorb water. Both perlite and vermiculite lack mechanical strength and in outdoor soils they soon collapse, impeding rather than enhancing drainage. They are not recommended for use outdoors. Hydrogels

These are inert polymer crystals that swell with water, which is then released slowly to plants as needed, preventing or delaying drought stress. They are presumed capable of soaking up and storing a hundred times their own weight in water. Full expansion of the polymers may take up to six hours. Plants will still need the same amount of water, but the use of hydrogels reduces the frequency of irrigation. They are best used in containers such as hanging baskets. Otherwise, they are not recommended for outdoor use.

In xeriscape design, plants are separated into zones according to their water needs.

Dried and baled, peat moss is an excellent amendment, adding organic matter and improving soil aeration as well as its ability to hold water.

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Creating the Prairie Xeriscape

CHAPTER 4

Irrigation Every Drop Counts When your landscape plants need more water than nature can provide, you can either grow different, more drought tolerant plants or add more water through irrigation. Your choice of plants influences how much extra water will be needed. On the prairies, with an average annual precipitation of 30 to 50 cm (12–20 in.), most conventional lawns and many other plants will require some degree of irrigation. If you choose very drought-tolerant plants, however, you may not need any extra water at all. The philosophy of xeriscape irrigation is to satisfy the needs of plants without wasting water. We’re beginning to understand just how scarce and precious our water resources are, so water conservation should be central to the design of your irrigation system. Whether you use a hose or install an underground irrigation system or any combination of the two, you can reduce water use by more than 20 percent through careful landscape design and irrigation options, grouping plants in zones according to their water needs and then coordinating and fine tuning both so that little water is wasted.

The Science of Water and Soil Knowing the relationship between soil and water and understanding why plants need water and how they absorb, store and conserve water will help you irrigate in a manner that encourages optimum plant growth while minimizing water waste and reducing water costs. As explained in the chapter on soils, solid matter makes up only about half of the volume of an average soil. Most of this

Conserving water from roofs is a technology that has been used for centuries. Water catchment containers can vary from traditional oak barrels to fiberglass, plastic, to metal. Many municipalities provide them to residents at low cost.

solid matter is broken-down rocks, varying in size from large particles of very coarse sand to microscopic particles of clay. The other half of the soil is the liquid or air that takes up the

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47

pore space surrounding the solid soil particles. The larger air Other Factors Affecting Water Movement Compacted soils have fewer pore spaces and therefore have less water available for plant use and reduced water-holding capacity. Shallow soils hold less moisture than

spaces are called macropores, the smaller spaces micropores.

When You Water or When It Rains... Water, whether from rainfall or irrigation, percolates into the soil from the surface, filling the pore spaces between the solid soil particles and forming a “wetting front.” The water displaces

deep soils. Stratification – the layering of soils of dif-

the air within the pore spaces, until the soil has reached the “sat-

ferent textures – interrupts and slows the

uration point.” This usually occurs for only short periods during

movement of water by capillary action and

and immediately after rainfall or irrigation.

impedes its downward percolation. An ex-

Once the pore spaces closest to the soil surface are filled, the

ample would be a layer of clay below a san-

water moves downward and to a lesser extent horizontally, fill-

dy soil or a layer of sand within a clay soil.

ing up the next layer of pores. Gradually, gravity pulls the water

The layer acts as a barrier until a relatively

downward, removing excess water from the larger pore spaces

high moisture level has been built up. Hardpans, often caused by repeated cultivation to the same depth, slow down the rate of water movement into the soil. They reduce the soil depth from which moisture can be drawn. Both stratification and hardpans may contribute to saturation, oxygen depletion and death or injury to plants.

of the upper soil layers, usually within forty-eight hours after a heavy rain or irrigation. The soil is then said to be at “field capacity.” It is moist because there is water in the micropores, but excess water will no longer drain from it. Below the wetting front, the soil remains dry. Optimal plant growth occurs at this point, when soil water is kept near field capacity and the pore space is approximately

Salts strengthen the hold soil particles

50 percent air and 50 percent water. Gravity has drained excess

have on water, thus decreasing the water

water from the larger pores and its place has been taken by air.

available to plants. Salts can be buffered to

The remaining water is held in the micropores. It is either used

some extent by the addition of generous

by plants or evaporates from the soil surface into the atmo-

amounts of organic matter.

sphere. Water that has moved below the rooting zone of plants is also unavailable to plants and is basically lost to their use. Plants can remove moisture from the soil quite rapidly until the soil particles and tiny micropores hold the remaining water so tightly that it is no longer available for plant use. The soil is then at the “permanent wilting point,” and if there is no rainfall or irrigation, plants usually die.

Soil Matters Different soils absorb and hold water at different rates. The amount of water the soil is able to absorb is referred to as its “moisture-holding capacity” and is directly related to the organic matter content of the soil and the soil texture. The greater the organic matter content, the more water a soil is able to hold. Soil texture refers to the relative proportion of sand, silt and clay Adding peat moss and other organic amendments to your soil increases its water-holding capacity.

48

Creating the Prairie Xeriscape

particles in a particular soil. Sandy soils absorb water quickly but have a low water-holding capacity, so they lose it quickly too. The same volume of water moves further and more rapidly in

sandy soils as compared to clay soils. If water is applied as drip irrigation, the wetting pattern is usually deeper but not as wide in a sandy soil compared to a heavier clay soil. The infiltration rate is the rate at which water is absorbed into the soil. Sandy soils have a fast infiltration rate but will have to be watered more frequently. Clay soils are able to absorb and hold a great deal of water but have a very slow infiltration rate and are prone to runoff and puddling. How does this apply to watering or irrigation? The plants themselves will require the same amount of water whether grown in a clay or sandy soil. But plants grown in a sandy soil will have to be watered more frequently to obtain the same volume of water. 2.5 cm (1 in.) of applied water will penetrate to a depth of about 30 cm (12 in.) in a sandy soil and to about 15 cm (6 in.) in a clay soil.

Water and Plants Plants are made of water. Water makes up 80 to 90 percent of annual and perennial plants by weight and about 50 percent of trees and shrubs. Plant growth requires enormous quantities of water. An average-sized tomato plant requires 115 L (30 U.S. gal.) of water in a growing season. A single 15 m (50 ft) silver maple is estimated

Plants use more water than we imagine. A mature silver maple is estimated to use 220 L per hour during a warm sunny summer day.

to use 220 L (60 U.S. gal.) per hour during a hot, sunny day. In a hardwood forest, each tree may transpire 30,000 L (8,000 U.S. gal.) of water per day during the summer. All chemical reactions in plants take place in solutions composed mainly of water. Both photosynthesis and nutrient transport depend on water. Soil nutrients are brought to the root, enter the root and are carried through the plant in water. It is the internal water pressure that causes cell walls to stretch and cells to grow. As each of the many thousand cells forming a plant enlarges slightly, we see the overall effect as plant growth. Water within the cell acts in much the same way as air in a balloon. It not only enables plants to grow, but it also allows them to stand upright. A plant that does not have enough water pressing against its cell walls appears wilted.

How Water Moves Through Plants Almost 99 percent of the water that enters a plant through its roots exits the leaves soon afterward as vapour. Why? In order to get water to its leaves, the plant must lose water through evaporation. This process, called transpiration, pulls water to the top

Water within each plant cell allows plants to stand upright. When plants do not have enough water pressing against their cell walls they begin to wilt.

Irrigation

49

of even the tallest trees. Each time a water molecule evaporates from the leaf at the top of the tree, xylem vessels pull up another molecule. Because of water’s strong tendency to hold together in drops, it takes less energy to pull the entire chain of molecules than it would to break it. If the soil is unable to supply enough water to maintain the chain, guard cells close the tiny holes in the leaves called stomates, preventing further water loss. A second major function of transpiration is cooling. As water evaporates from a leaf into the surrounding air, it removes heat from the plant. The effectiveness of this method is obvious when you consider the temperature difference of a lawn and an adjacent sidewalk on a hot day.

Photosynthesis: Relating Food Manufacture to Water Stomate closure caused by a lack of water in the soil reduces moisture loss but also cuts off the plant’s supply of carbon dioxide, preventing photosynthesis, the process by which plants manufacture sugar. Since photosynthesis is the primary means by which plants generate their food supply, frequent stoppages can lead to an overall decrease in plant growth. This is one of the main reasons why a plant growing under drought conditions will be smaller than a similar one with an abundant water supply.

Water and Roots Water passing through a cell membrane always moves from an area of higher water purity to an area of lower water purity. Because plant cells contain sugars, salts and other dissolved substances, the water in soil is usually more pure than the water in a plant. Therefore the relatively pure water from the soil diffuses through the thin wall of the root cell and moves into the less pure water of the root. Plant roots contain a high level of salts, particularly potassium salts, encouraging the diffusion of water from the soil into the root. This is why plants find life difficult on saline soils. The It is the tiny white feeder roots of plants that absorb water, not their leaves. Plant roots contain a high level of salts, especially potassium, which encourage the diffusion of water from the soil into the roots.

more pure water in the root flows out into the less pure water of the soil and the plant suffers a water deficit, causing wilting and often death.

Garden Practices that Conserve Water The first step in reducing water use is to choose your plant material carefully. Nature should be your guide. Select plants that are found naturally in the same environment as your garden. A birch tree from a cool, moist river valley will almost certainly

50

Creating the Prairie Xeriscape

decline and die on an arid site without considerable supplemental water. A drought-tolerant green ash from further up the slope of the same river valley will survive much more successfully in a dry garden. Ideally, water should be applied to the soil, where it can be absorbed by plant roots, rather than to the foliage. When watering established plants, always water deeply and thoroughly, to the depth of the root system and beyond to encourage deeper rooting. Roots will only grow where soil is moist. They will not extend into dry soil. Frequent shallow watering confines roots to the upper level of the soil, leaving plants with shallow roots and therefore prone to rapid drying between waterings. Enhanced root growth allows greater water uptake. A spring application of bone meal, which contains phosphorus, promotes root growth. Be aware of competition from aggressive shallowly-rooted plants with extensive, fibrous root systems. Lawns, ground covers and herbaceous weeds are particularly competitive and rob valuable soil moisture from newly planted trees. The shallow, far-reaching roots of poplar, Manitoba maple, Siberian elm and spruce, however, effectively compete for moisture intended for

The shallow, far-reaching roots of Manitoba maple are very competitive for soil moisture. Along with poplar, elms and spruce, they should not be planted near lawns, vegetable gardens or beds.

a nearby lawn, vegetable garden or flower bed. Concrete, pavement and large buildings increase air temperatures and limit water availability. Buildings may also funnel wind, often greatly increasing its velocity. Trees and shrubs in highly urbanized settings will lose more water than trees in natural, park-like settings.

Designing for Water Conservation Several aspects of design lend themselves to water conservation: developing irrigation zones, shaping irrigated areas to conform to sprinkler patterns, grading to prevent runoff and encouraging water catchment. You may want to create deeper soil profiles, well amended with compost, to improve the water-holding capacity of soil in specific planting beds such as perennial or mixed borders.

Zoning In conventional landscape design, we consider function, height, colour, texture and season of bloom, but seldom do we think of the water needs of plants except around ponds and streams or in exceptionally hot, dry areas. We often combine plants regardless of their drought tolerance and then water the entire bed to

Although undoubtedly attractive, unzoned beds that combine plants without regard to their water needs are wasteful of water. It is better to separate plants according to their water needs and then consider height, color, texture and season of bloom.

satisfy the plants that require the most water.

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51

Typical landscape water waste Much of the water directed towards plants never reaches them. The majority is lost to evaporation and runoff. Some of it ends up on non-target, unplanted areas and some is leached below the root zones of plants and effectively lost to their use. Evaporation losses are affected by temperature, relative humidity, wind, droplet size and water pressure. While it is impossible to control temperature and relative humidity, wind can be decreased by shelterbelts, screening with trees and shrubs and fencing. Evaporation losses can also be reduced by irrigating when it is calm and cool and the relative humidity is high, usually in the very early morning. A spray directed at a higher angle covers a greater area, but considerably more water is lost to evaporation and wind drift because the water is in the air longer and wind becomes stronger with increased height. The lower the “angle of trajectory,” the less wind drift and evaporation.

52

Overspray is water that ends up on non-target/ unplanted areas such as patios and driveways. It can be reduced by lowering water pressure or changing the spray-head location or type, the method of irrigation or the shape of the planted area.

In windy areas, an angle of no more than 25°

runoff and may require an alternate on/off irri-

above the horizon is recommended.

gation schedule or terracing to reduce runoff.

Higher pressure usually breaks up the

Overspray is water that is delivered beyond

stream of water into smaller droplets which are

the landscaped area, usually to adjacent drive-

more easily lost to evaporation and wind drift.

ways, walks, decks, patios or nonplanted areas.

Runoff is water that flows from the target

Overspray can be reduced by lowering water

area. It usually occurs when water is applied

pressure or changing the spray-head location

more quickly than it can be absorbed by the

or type, the method of irrigation or the shape of

soil. Infiltration rates are determined by soil

the planted area.

texture and slope. In any given soil texture,

Leaching occurs during and after excessive

water infiltrates quite readily when the soil is

rainfall or irrigation when water and min-

dry. Once the larger pore spaces are filled with

eral nutrients dissolved in the soil water are

water, the absorption rate falls off rapidly.

washed below the plants’ root zone. This rep-

Select a sprinkler with a delivery rate com-

resents a loss of both water and nutrients to

patible to the soil’s infiltration rate. If your

plants and possible contamination of ground-

existing irrigation system produces runoff,

water. Check to see how long your irrigation

schedule “off” periods during the course of the

system takes to moisten the soil to the desired

irrigation to allow for infiltration. Slopes of more

depth (generally 30–45 cm/12–18 in.) and then

than 10 percent are particularly vulnerable to

schedule irrigation accordingly.

Creating the Prairie Xeriscape

In xeriscape design, plants are first separated into zones according to their water needs and then arranged with design factors such as height or colour in mind. Plants are divided into those with low water needs (such as yucca, lilac and shrub roses), moderate water needs (cranesbill geranium, basswood and dogwood) and high water needs (birch, delphinium and hosta). By grouping plants into zones based on their water needs and then watering them accordingly, we make irrigation more efficient. Each landscape zone is served by a single type of irrigation and scheduled as a single unit. As well as plant needs, irrigation requirements for each zone should consider: soil type (clay, sand, silt or loam) and its infiltration rate; microclimate, including sun/shade, reflected light and heat, presence of heat-retentive hard surfaces and shelter/wind; root competition with neighbouring trees; and topography – slopes will have a different infiltration rate and need a different irrigation schedule than flat areas.

Shape and Grade To avoid compromising aesthetics, professional landscape designers usually develop the design first and then adjust the

All of the plants within this “hot” border of reds, oranges and yellows have moderate water needs. By grouping plants into zones based on their water needs and watering them accordingly, irrigation becomes more efficient and water conserving.

irrigation system to fit. However, knowing the type of irrigation head or emitter that is appropriate for a particular zone and then shaping the zone to fit the overall delivery pattern of the irrigation device to be used ensures more efficient use of water. By working back and forth between the design and the irrigation system and modifying one or both on paper as you go along, an attractive, water-conserving landscape can be achieved. Slopes and banks are an invitation to runoff. Conserve water by regrading to direct water towards plantings, terracing, providing water-catchment areas at the base of slopes with organic matter to improve water percolation and applying water slowly to prevent runoff. Depressions, called swales, at mid-slope or at the base are channels used to catch and redirect runoff water to where it can be used. Aerating sloped grassy areas increases water percolation. Ensure that the grade slopes away from buildings to avoid water in your basement or a neighbour’s. Be aware of local bylaws concerning the legalities of water movement across adjacent properties.

Water Catchment Water catchment means catching water – usually rainfall – that might otherwise be lost and directing it towards plantings

Swales are depressions in the landscape used to catch water and redirect it to where it can be used. They can be on a large scale as shown here or on a small scale within an urban lot.

or holding it for later use.

Irrigation

53

Bowl-shaped depressions around individual trees and shrubs ensure that irrigation and rainwater are directed towards root systems rather than lost as runoff to adjacent nonplanted soil. But water catchment can be done on a larger scale. The most obvious source of water catchment is our roofs. A 100 m2 (1,000 ft2) roof will catch an estimated 630 L (165 U.S. gal.) of water in the course of a 6 mm (¼ in.) rain. But as long as it is not going into our basements, most of us never think about where that water might be useful. A number of catchment options or combinations are available. By using plastic adapters, downspouts can be extended to nearby plantings. Cobblestone or brick swales (sometimes called dry stream beds) can also direct water from downspouts Dry stream beds are like swales in that they direct water from where there is too much (like a roof) to where it can be used in our landscapes.

to planting beds. Downspouts can funnel water into rain barrels or holding tanks for later use. These plastic or metal containers should be placed on a firm, level base and be equipped with a lockable lid, screened inlets to exclude birds and animals and an overflow mechanism to direct excess water away from house foundations. A bottom spigot to which a hose can be attached facilitates use. Drain rain barrels prior to freeze-up in the fall. You may be working with a public area and have a lot of water to deal with. If catchment is to be from a relatively large area of roof, a combination of roof and a slightly sloped driveway or parking area or a basement sump-pump, it might better take the form of a landscaped holding pond lined with vinyl, concrete or clay. Water can be delivered to plantings as needed by gravity or a pump. High volume extenders are also available By slightly sloping driveways and walkways towards landscape areas, you can cause water to run off onto adjacent lawns or beds rather than flowing directly to the street and storm sewers or simply puddling and then evaporating from the hard surface.

Irrigation – Delivering Water to Plants Extenders attached to downspouts direct water away from house foundations toward planted areas. High volume extenders, as shown here, are also available.

Scheduling Scheduling irrigation involves knowing the water needs of plants, the evapo-transpiration rates during the hottest, driest period of summer, the infiltration rate of the soil in which they are growing, the amount of water your sprinkler delivers and the microclimate in which the plants are situated.

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Creating the Prairie Xeriscape

Ideally, the entire root zone should be filled with water and the soil allowed to partially dry out prior to the next watering.

“Like laundry on a clothesline”

Plants are generally more tolerant of moderate drought than

Most water taken up by the plant is lost

prolonged saturation because saturation limits oxygen availability to the roots, effectively suffocating them. While the slogan for automated irrigation was once “set it and forget it,” such scheduling is usually based on presumed

through evaporation, and as with wet laundry on a clothesline, factors in the environment will speed or slow the rate of drying that occurs. Shade reduces the water needs of a plant

hot, dry weather and operated at that timing and duration

by lowering the surrounding air tempera-

throughout the growing season regardless of actual need. We

ture. The shaded side of a tree loses about

have all seen public and private sprinkler systems going at full

25 percent less water than the sunny side.

tilt in the midst of a torrential downpour and have shaken our

A forest tree shaded by many neighbouring

heads in wonder at technology overriding common sense.

trees loses considerably less water than a

Automated systems can be far more wasteful of water than

lone tree standing in full sun and exposed

human “hose draggers.” Timers and control panels can be com-

to wind. But while the forest tree may lose

plicated and intimidating and many people are reluctant to

less water, its roots must compete with

make adjustments and fine-tune them once they have been set

neighbouring trees for available soil mois-

by the installer. A far better approach is to explain your irrigation philosophy and needs to a professional irrigation specialist and install a system that is both adaptable and user-friendly. Some controls allow you to adapt to seasonal variations by overriding the pro-

ture to replenish water losses. Humidity affects water use. The humidity level over large areas of concrete is significantly lower than the humidity over a lawn or surrounding other living plants. In dry air, water evaporates more readily and plants

grammed amount so as to deliver less or more water. Irrigating

dry more quickly. Plants increase the humid-

on an “as needed” basis is the most efficient manner of schedul-

ity immediately around them by releasing

ing in terms of water use.

water through transpiration. In a dense tree

Moisture sensors and rain shut-off devices are used to over-

canopy, water lost through transpiration will

ride preset timers and automatically turn on or off irrigation

humidify the air, slowing the rate of water

systems. Automatic rain sensors override preset scheduling so

loss from other leaves.

that irrigation does not take place during rainfall. When a pre-

Wind greatly increases the rate of evapo-

determined amount of water accumulates in a collector cup,

ration from leaves. Plants exposed to wind

the system is shut off. Once the cup is empty, preset scheduling resumes. Empty tuna cans also work but are not “automatic”. Soil moisture sensors tend to be expensive, may need periodic replacement and may not be 100 percent reliable. Soil moisture

dry much faster than those in calm air. By reducing wind velocity, shelterbelts reduce water loss from the landscape plants they enclose. Temperature dramatically affects wa-

sensors such as tensiometres and gypsum blocks work best if

ter loss from plants. Plants lose water

installed in each zone. They indicate the amount of moisture

more quickly on hot days. Water uptake

available to plants and, coupled with automatic on and off valves,

is slowed by low soil temperatures. Ever-

determine scheduling. You will need to correlate soil moisture

greens often show dieback due to spring

levels with plant needs within each zone to determine at what

drying. On a hot spring day, the top of a

percent soil moisture the system should be turned on or off.

plant may become very warm, causing an increase in transpiration, but the roots re-

How Much Water? The amount of water needed by a particular plant will depend

main locked in cold soil and are unable to replenish the water as quickly as it is lost.

on: the type of plant, its age, size and root depth; weather;

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55

microclimate; soil; and competition from other plants. Small plants with shallow root systems will need to be watered more often but for shorter durations than will larger, deeper-rooted plants. As plants grow, irrigation can be less frequent but for longer periods of time. The larger the area of moist soil, the less danger of stress if watering is delayed for some reason. With established plants, begin by watering once a week and decrease (or less often, increase) the frequency of irrigation based on observation of the plants.

How Do I Know When to Irrigate Again? Rain sensors can over-ride prescheduled irrigation systems so they will not operate when there has been sufficient natural precipitation. Empty tuna cans strategically placed within an irrigation zone can also determine when you have watered enough.

Knowing when to water can be determined by the feel of the soil. If the soil is too dry to form a ball when a handful is firmly squeezed, you’ve waited too long to water. If it is moist enough to form a ball but is somewhat crumbly, it’s time to irrigate. If it forms a durable ball and is slick, there is no need to irrigate yet. Water before signs of moisture stress are evident. Wilt, colour change (as the soil dries out, lawns change from green to dull green to blue-grey to grey), leaf roll-up, burning of leaf tips and margins or, in extreme situations, leaf drop are all signals that plants are in need of water. By the time these symptoms are evident, damage will already have occurred. Ultimately, irrigation scheduling should be based on your cumulative experience with your plants, their micro-climate, soil and irrigation system.

The Best Time to Water... The optimum time to water is early morning, when it is calm, cool and relative humidity is high. Little water is lost to evaporation. Plants dry quickly once the sun rises, reducing the risk of foliage diseases such as powdery mildew, which proliferate rapidly under moist conditions. It is also a nonpeak time for domestic water use, so municipal water facilities are less likely to be overtaxed. If you do not opt for an underground system, installing a timer on a garden hose and sprinkler is well worth the effort.

Trees and Shrubs Are Not Lawns Watering your lawn does not mean you have watered the trees An automatic timer on a hoseend sprinkler allows you to water a predetermined amount without fear of forgetting to turn off the tap.

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Creating the Prairie Xeriscape

in it. Remember, a maple tree can use over 200 L (50 U.S. gal.) of water per hour. Regardless of their drought tolerance, newly planted trees and shrubs will need regular watering from planting time to

establishment – usually two or three growing seasons. Dig bowlshaped depressions around newly planted trees and shrubs to direct water towards the plants’ roots rather than onto adjacent soil. Applying an organic mulch of 10 cm (4 in.) reduces water loss to surface evaporation. Water – or check the soil to see if water is needed – twice a week during their first month and once a week for the remainder of that season. During the second and third season, water deeply twice a month or as needed. Mature trees should be watered during periods of extended drought at their drip line rather than at their trunk. The drip line is the soil area below the furthest extent of the tree’s branches. Feeder roots – those which absorb water and nutrients – usually end just beyond the drip line and are usually within the upper 40 cm (16 in.) of soil. Set a soaker hose under the drip line and leave it on until the soil is moist to that depth. Discontinue watering in late September or early October, when deciduous trees have coloured and begin to drop their leaves. This is your signal that they’re beginning to harden off for winter in response to progressively shorter days and colder temperatures. Continuous watering or the application of fertilizer in late fall may slow the process, leaving them vulnerable to

When trees or vines such as Virginia creeper begin to colour in the fall, this is your signal that it will soon be time to discontinue watering and allow plants to harden off for winter. Once leaves have fallen, water deeply prior to freeze-up.

winterkill. Once all of the leaves have fallen, give them several deep waterings prior to freeze-up. The objective is to allow them to harden off, yet enter winter dormancy with ample water in their tissue and the surrounding soil. This reduces vulnerability to late winter and early spring desiccation.

Irrigation Systems How you water your plants can vary from a hand-held watering can or hose, to a hose with a sprinkler, to an underground irrigation system.

Portable Systems There are a variety of portable sprinkler systems. Watering with a watering can involves time and patience to be done properly. It is really appropriate only for containers or small beds. Other portable irrigation methods, however, work well in a variety of applications. Many of us are hose draggers. We use a hose with one or more types of portable sprinklers and move them around as

Galvanized watering cans may become a collectors item but they are still appropriate for small beds and containers.

needed. While it may not be as convenient and involves more time and labour, there are a number of advantages to a “manual portable system.” It’s certainly less costly. It is also less

Irrigation

57

wasteful – hauling out a hose takes more effort than turning on a valve or flipping a switch, so we usually don’t do it unless we feel it’s necessary, thereby saving both water and money. A hose is also flexible (unless it’s vinyl and it’s early April). If we alter our landscape it does not necessitate excavating and redesigning an irrigation system. As with any type of irrigation, portable sprinklers should provide uniform coverage – the area next to the sprinkler should receive the same amount of water as the area at its farthest extent. The delivery rate of the sprinkler (called the precipitation rate) should not exceed the infiltration rate of the soil. This rate, Portable hose end sprinklers, regardless of type, should provide uniform coverage. The area next to the sprinkler should receive the same amount of water as the area at its furthest point.

which will be influenced by water pressure, is usually marked on the sprinkler or its packaging: “2.5” indicates that the sprinkler delivers 2.5 inches of water per hour. Sprinklers that cover a small area usually have a higher delivery rate than sprinklers that cover a larger area They require more frequent moving, but they water more deeply in a given period.

Types of portable sprinklers Impulse or impact sprinklers are usually considered the most efficient in terms of uniformity of coverage. They are available in a range of precipitation rates. Balanced coverage is obtained by moving the sprinkler to a number of locations and overlapping coverage. Revolving sprinklers have arms rotated by water pressure. If not well designed they do not provide uniform coverage. High pressure creates a poor distribution pattern. Low pressure may not provide sufficient force for rotation. Fixed sprinklers shoot water through a pattern of holes on their top. They are variable in quality ranging from excellent (a small metal design with no moving parts) to poor (low-quality plastics that leak and distribute most of the water close to the sprinkler). Consumer information on uniformity of coverage is seldom available. Oscillating sprinklers move back and forth, covering a square or rectangular area. They often deliver more water at the far ends of their pattern where they pause to reverse direction. Some have a pulsating feature designed to reduce this.

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Creating the Prairie Xeriscape

Portable sprinklers vary in their coverage and delivery rate. To ensure complete and even distribution, the amount of water should be measured at several locations during irrigation. Place a number of identical containers throughout the area to be watered. Variations of up to 20 percent are tolerable without harming plants. Remember, the pressure of your water system can vary as much as 15 or 20 psi over a few hours of watering on a hot summer day.

Underground Irrigation Systems At their most basic, underground irrigation systems consist of a pressurized water source, control valves, underground pipes and sprinkler heads or drip emitters. While underground systems for smaller landscapes may be manually activated, with the addition of an optional timer or control panel, each zone can be scheduled differently to meet the needs of plants within that zone. The controller or timer is a clock that opens and closes electrically operated valves on designated days for specified durations. Designing and installing a fully automated underground irrigation system involves a lot of homework and a professional installer who is sensitive to your philosophy of water use. Most irrigation companies are willing to work with homeowners to design an effective and efficient automated underground irrigation system. While underground systems are convenient and save time, they are more expensive than other types and their installation requires excavation. Properly installed, an underground system will provide uniform coverage of the area being watered. Many choices and combinations of timers, controls, pipes and sprinkler heads

Large areas of lawn are best irrigated with an underground system using rotary stream spray heads. Pressure must be adequate for these to operate efficiently.

are now available. Their efficiency, in terms of water savings, is related to their design, the scheduling of water delivery and monitoring and maintenance during operation. System Design

The design of a sprinkler system is based on precipitation rates. This is the amount of water that a system delivers at any point in the irrigated area. It is measured in inches per hour. Manufacturers’ rates do not take into account evaporation, wind loss or runoff. Sprinkler heads distribute water through pressure. If water pressure is low, coverage will not be adequate. If water is forced out of a spray head at too high a pressure, it will no longer form water drops but will tend to become a mister and much of the water will evaporate into the air rather than be used by plants.

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59

Types of sprinkler heads Sprinkler heads are either static and set at their operating height or of the “pop-up” variety, which automatically lift up when in use then return to their “seat,” out of the way of mowers and people, when not in use. Pop-up heads operate like a spring-loaded pipe. In the absence of water pressure, the spring pulls the nozzle down. When water is turned on, the pressure of the water pushes the nozzle up. Regardless of whether they are stationary or pop-up, sprinkler heads are of several types: fan spray, rotary stream spray or bubbler.

Fan spray heads Fan spray heads emit fine sheets or fans of water. In lawns, they are usually set to pop up about 10 cm (4 in.), allowing clearance over long grass. In beds, sprinklers can pop up as high as 30 cm (12 in.) or nozzles can be set on fixed risers at whatever height is most practical for a particular type of plant. These heads are most efficient for annuals, perennials, ground covers and lawns. They operate at 20 to 30 psi and cover a radius of 1.5 to 5 m (5–16 ft). They are one of the most flexible and efficient systems for small landscape areas. Fan sprays have no moving parts and cover the entire area to be watered simultaneously. They distribute a fine, uniform spray of water droplets, but because the holes are smaller, their nozzles plug easily. They have a fixed spray pattern. Nozzles are calibrated to provide uniform coverage when different spray patterns from different nozzles are combined within a single zone. Variable arcs are available so spray patterns can be adjusted for proper coverage of awkward angles. Precipitation rates vary from 4 to 7.5 cm (1.5–3 in.) per hour.

Rotary stream sprays These heads are useful in large, open lawn areas on acreages, farmyards, parks and golf courses. Water pressure (30 to 80 psi) is used to power an impact (sometimes called impulse or gear-driven) mechanism, which delivers single or multiple streams of water from a rotating sprinkler head. Its range is usually 9 to 18 m (30–60 ft) but can be reduced to 6 m (20 ft) or extended to 34 m (110 ft). Where full or part circle coverage is combined in one zone, nozzles should be selected to provide balanced coverage. Precipitation rates (5–20 mm per hour/0.2-0.8 in. per hour) are somewhat low because water is spread over a larger area.

Bubblers Bubblers deliver water to a smaller area simultaneously. This type of head is best suited for tree wells, shrub beds and mixed planting beds of ground covers, annuals, perennials and shrubs. Bubblers have a range of up to 1.5 m (5 ft) and can apply from 2–7.5 L (0.5–2 U.S. gal.) per minute. Runoff may occur if they are left on too long or if the soil within the planting bed has not been prepared properly to maximize infiltration.

60

Creating the Prairie Xeriscape

Sprinkler heads should be spaced according to their rated performance, matching their water-delivery rate to the infiltra-

Fan spray heads

tion rate of the soil. On a square metre basis, it is cheaper to

Advantages:

install fewer sprinkler heads that each cover a larger area than

• parts are readily available at low cost

it is to install a larger number of sprinklers, each of which covers

• wide selection of nozzles

a smaller area.

• operate at low pressure

Sprinklers are about 85 percent efficient, in that 15 percent of the water dispersed is never absorbed by plants. Sprinkler heads should deliver water as close to the ground as possible to reduce evaporation losses and wind deflection. Spray heads normally have a trajectory of 23° to 30°. The lower end of this range reduces wind drift and evaporation. Within each zone, heads operating from the same valve should be of the same type and apply the same amount of

• reduced spray distance ensures greater

control in smaller landscapes

Disadvantages:

• debris may block nozzle • precipitation rate is fairly high, which may cause runoff on slopes and puddling on heavier soils that have a slower infiltration capacity

• under high pressure, the spray may break

up, causing excessive wind drift and misting

water to the area they cover. For example, a full circle spray

• under low pressure, the spray distance

head would apply 11 L (3 U.S. gal.) per minute on a 4.5-m (15

may be reduced, resulting in incomplete coverage

ft) radius. A matching spray head that covers only a half circle should apply 5.5 L (1.5 U.S. gal.) per minute because the area of

• because it requires many heads, the

system is more expensive to install.

coverage is one half that of the full circle. Maintenance

Rotary stream sprays

Besides the usual fall winterization and drainage, which

Advantages:

increases the life and lowers maintenance costs of irrigation

• economical system for area covered

components, maintenance from a xeriscape perspective means

• fewer materials required for installation

observation. Overhead systems should be checked after instal-

• slower precipitation rates result in less

lation and then monthly during the growing season: Within each zone, do sprinkler heads pop up and then return to their seat? Are any heads broken or blocked? Is the spray pattern

runoff

Disadvantages:

• high pressure can cause some heads to

uniform? Is pressure too high, creating fog or mist instead of



drops? Is pressure too low, so that coverage is not complete?

• low pressure prevents heads from

Are there slow leaks, usually indicated by a higher-than-normal water bill or localized wet or “lush” areas that may show algae



rotate quickly, causing misting or reducing coverage rotating, reducing coverage and causing pop-up problems

• strong winds elongate spray patterns

growth? Is the duration of the irrigation sufficient to water the

• longer operating time required to obtain

soil to an adequate depth to satisfy the needs of plants within



each zone (an amount that may change through the growing season with weather changes)? Is the spray pattern covering the intended areas? Also look at excess evaporation due to high trajectory angles of sprinklers. Is there runoff, overspray into non-target areas or excessive watering below the root zones of plants? Do delivery rates exceed infiltration rates? Once problems have been pinpointed, make adjustments to

necessary precipitation

Bubblers Advantages:

• useful for tree wells, shrub beds and mixed

plantings in smaller landscapes

Disadvantages:

• runoff or puddling if left on too long • require thorough bed preparation

the system to improve water efficiency.

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61

Drip irrigation

Drip Irrigation Drip irrigation systems (also called trickle, microirrigation, low-

Advantages

flow or low-volume irrigation) apply water slowly and under low

• easy and relatively inexpensive to install

pressure to the root zone of each plant, maintaining near opti-



and requires less excavation than under-ground systems

• less water is needed since very little

mum levels of soil moisture. Drip systems are close to 100 percent efficient, in that almost

is lost to evaporation, wind or runoff and none is applied to unplanted or weedy areas or hard surfaces

all of the water is delivered to the root zone of the plant. But

• energy savings due to lower pumping

ground covers or most flower beds. They work extremely well



where nonspreading plants are grown in rows (although for

costs and lower pressure

• because of the low flow rates, soil is

seldom saturated to the exclusion of oxygen

they are not suited to the entire landscape – certainly not lawns,

design purposes, these rows may be curved). Drip irrigation is most often used in vegetable gardens, young shelterbelts or tree

• results in fewer weeds, reducing

plantings, with fruit such as strawberries and raspberries and



in orchards.

maintenance and pesticide use

• plant stress is reduced • no damage to plants by water impact • fewer disease problems because the

foliage remains dry

• because only the soil immediately

surrounding each plant is wet, drip irrigation does not interfere with other gardening tasks

• because these systems require lower

Maintenance

Lateral lines should be flushed out immediately after installation or any repairs to the system, prior to the first irrigation each spring, monthly during the growing season and at the end of each season to remove any accumulated sediment. Remove the clamp at the end of each lateral line and turn on the water for five to ten minutes until all particles have been flushed out.

water volume and pressure, they lend themselves to rainwater collection as long as good filters are in place

Disadvantages

• because you can’t actually see what’s happening below the wetted surface, gardeners may initially lack confidence in the system; digging a few times to check the depth of water infiltration is reassuring

• the system requires a filtration system since emitters are easily clogged with fine soil, organic particles and algae

• most systems require pressure regulation • lateral lines are vulnerable to damage from machinery, hoeing, birds and animals

• emitters must be checked regularly to ensure that they are working

• there is potential for salt accumulation at the edge of the wetted area

• winterization must be carried out with

62

care to avoid damage to the lines; systems designed with a valve placed at terminus of pipe run aid in quick and thorough draining of water

Creating the Prairie Xeriscape

Drip irrigation can be used in ground beds (right) as well as in containers (left). It applies water slowly and under low pressure to the root zones of individual plants, giving them near optimum levels of soil moisture.

Components of drip irrigation systems Drip systems are composed of a head or con-

the length within which emitters will deliver a

trol system, a main delivery line and lateral

uniform amount of water.

lines with emitters. The head

Emitters deliver 2 to 15 L (0.5–4.0 U.S. gal.) of water per hour and are usually placed next to

The head consists of a control station with a

individual plants along the lateral lines. Water

pressure regulator, filter, back-flow preventer

emitted from the line moves by capillary action

and control valve. Optional timers are available.

beneath the soil surface. The actual size of the

Water flows into the head, where it is measured,

wetted area of soil is determined by the soil

filtered and regulated through pressure and tim-

texture, the delivery rate of the emitter and the

ing. Soil or organic particles must be removed

duration of irrigation.

by filtering to prevent blockage of the emitters.

If salts are present in the soil, water released

Because emitters are designed to operate at a

from an emitter generally moves the salts away

specific pressure, pressure regulators are used to

from the plant towards the perimeter of the

reduce water pressure to a rate that is compat-

wetted area.

ible with non-pressure compensating emitters.

Conventionally, drip irrigation is sched-

High pressure on the lateral lines can cause the

uled more frequently than irrigation with

connections to come apart.

overhead systems and wets a relatively small

Main line

volume of soil, which plants deplete rather

A main line, usually buried and constructed of

quickly. Scheduling drip irrigation so that it is

polyethylene plastic pipe, carries water under

less frequent but wets a larger volume of soil

pressure from the head to the lateral lines,

encourages deeper rooting.

which branch from it and have control valves

To prevent clogging, most emitters have a

for each zone.

flushing action when the system is turned on

Lateral lines

or pressurized. As the pressure starts to climb, a

Lateral lines are designed in conjunction with

spurt of water from the emitter flushes particles

the emitters selected for a specific project. They

from the outlet.

are often covered with a mulch, for aesthetic

There are two main types of emitters: line

reasons, to prevent damage and to protect the

source, which is manufactured with a series of

tubing from deterioration caused by ultraviolet

regularly spaced outlets punched along a pipe;

light. If the system is more permanent, they are

and point source, which is punched where

buried at least 30 cm (12 in.) deep.

required at the time the system is installed.

Emitters

Emitters are rated in litres (or gallons) of

Each emitter along the lateral lines should pro-

water per hour, with normal rates of 2, 4 or 8

vide the same amount of water, plus or minus

litres (0.5, 1 or 2 gal.) per hour. They are avail-

10 percent. This is done by supplying water at

able in single outlet units or as multiple units

a set pressure (pressure regulating) or lowering

with up to eight outlets.

the pressure to a specified range at each emitter (pressure compensating). Each lateral line is designed to have a specific “allowed length of run.” This may be up to 120 m (400 ft) and is

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63

Other Options: Soaker Hoses and Porous Pipe Soaker hoses are long tubes of rubber or plastic with rows of tiny holes. They are connected to a garden hose and laid on the soil surface along the side of plant rows with the holes facing up or down. Facing the holes down reduces evaporation losses considerably but also limits the area that is wetted. If facing downward, the soaker hose may be covered with mulch. Soaker hoses deliver water fairly equally along their length provided they are no longer than 15 m (50 ft). Although cheaper than drip, they are not considered as efficient because of variation in hole sizes, although the use of lasers in the manufacture Composite rubber porous pipe is laid on or just below the soil surface. Little water is lost to evaporation, wind or to runoff.

of newer products has made them more reliable. Soaker hoses are portable but may be left in place indefinitely. The thin plastic types are easily damaged. Composite rubber porous pipe is a type of subsurface irrigation that was developed in the 1970s for crop use. Rubber chips

Soaker hoses Advantages

• excellent for drip line of mature trees • portable

are bonded together to form a hose with numerous holes along its length. Lines are buried 15 to 30 cm (6–12 in.) below the soil surface and water moves down through the soil by capillary action similar to line source emitters.

Disadvantages

• subject to wind losses if facing up • limited area is irrigated if facing down • limited length for even delivery • variations in hole size • easily damaged Composite rubber porous pipe Advantages

• similar to those of drip irrigation Disadvantages

• a tendency to under-water • clogging • root intrusion • animal damage • because the entire system is hidden,

it is more difficult to monitor than other types of irrigation and problems only become evident as plants start to wilt and die

• the bonding or rubber can break down

and change flow rates

• variations in chip sizes and material

64

densities cause variations in hole sizes and lead to uneven watering

Creating the Prairie Xeriscape

The three most obvious benefits of mulching are water conservation, weed control and soil improvement.

CHAPTER 5

Mulch Imitating Nature A careful look at the floor of a northern coniferous forest, an aspen bluff or our native grasslands should tell you a lot about mulching, not only about the product, but also about the process. For centuries, plants have been dropping leaves, twigs and branches onto the soil below. These form a layer of undecayed and decaying organic matter, eventually rotting and returning nutrients to the soil for reuse by other plants, as well as improving the soil structure. In the process, the self-made mulch conserves moisture by insulating the soil against temperature extremes and limits germination of weed seedlings by excluding light and forming a physical barrier. In contrast, gardens have traditionally been tidy places where bare soil is best, with not a single leaf allowed to fall onto a border. This is one of the values that lingers from agricultural practices of a bygone era. Farmers now know better, but while in agriculture change is essential, these practices continue unchallenged in our gardens: “black dirt” tilled within an inch of its life is still seen by some as a virtue. It’s time we looked at some of these practices with an eye to what’s actually going on rather than what our neighbours might think.

Why Mulch? Mulching is an integral part of the recycling process, using organic materials, many of which were formerly regarded as waste and sent to landfills, to safeguard soil and water. The three most obvious benefits of mulching are water conservation, weed control and soil improvement. It has other functions as well, including protecting plant roots from heat and cold and

Forest floors are naturally mulched with fallen leaves, needles and cones. These form a layer of organic matter, eventually rotting and returning nutrients to the soil, improving its structure, and conserving moisture.

keeping fruit clean. But what appears to be a simple process on the surface is really an intricate recycling of nutrients.

Mulch

65

Water Conservation There are many ways in which mulch conserves water. Weed suppression is one. Weeds compete with other plants for water. If weeds are controlled by mulch, more water is available to landscape plants. Organic mulches cool the soil, lowering temperatures at a 2.5 cm (1 in.) depth by as much as 6° to 8°C (11°–14°F). Cooler soils result in less evaporation. The percentage of soil moisture in mulched plots is approximately twice as high as in unmulched plots. A 5 cm (2 in.) layer of pine needles reduces evaporation by 65 percent compared to an unmulched soil. If the mulch layer itself absorbs moisture, it more than compensates for this in its reduction of evaporation of water from the soil. Soil under mulch is generally softer because it is protected from compaction and water impact. This increases water percolation and decreases runoff. By protecting the soil from wind, mulch further reduces evaporation. The surface of a planting bed mulched with a coarse-textured material is usually raised by 5 to 10 cm (2–4 in.). In many cases, this increased height and rougher texture is sufficient to act as a snow trap. The snow insulates the plants over winter and provides added moisture when it melts in the spring.

Weed Control Weeds compete with landscape plants for space, light, nutriHollyhock (Alcea rosea) is short-lived, but will self-seed if left unmulched.

ents and water. If you were to examine carefully the top several centimetres of soil, you would find thousands of weed seeds waiting to germinate. To germinate, they generally need moisture, warmth and light. The mulch layer prevents germination by excluding light. And if a few weeds do germinate, the physical barrier formed by the mulch makes their emergence almost

A cautionary note

impossible. Likewise, weed seeds that blow onto the surface of

Although it will stop many weed seeds

the mulch find it difficult to root through the mulch into the

from germinating, the mulch layer will also

soil below.

prevent self-seeding annuals, biennials and perennials from perpetuating themselves. Group such plants as hollyhocks and forget-me-nots together in the same bed and forego the mulch.

Controlling weeds by mulching avoids the root damage to plants that cultivation‚ either by tiller or hoe, so often inflicts. Damaged roots result in weaker plants that are less able to absorb water and soil nutrients and in suckering by some woody plants. Mulching suppresses weeds without damaging roots or stimulating unwanted suckering. And it is a much more environmentally friendly practice than the use of chemical herbicides.

66

Creating the Prairie Xeriscape

Soil Improvement and Conservation Mulched soil is far less prone to erosion and the loss of valuable topsoil. Mulch prevents crusting of the soil surface caused by the impact of water droplets, which hinders seedling emergence and water percolation. Crusting causes runoff; mulch allows slow and steady percolation. Maintaining more even soil moisture makes heavy soils less prone to the cracking and root tearing that occur as the soil dries. The word is derived from the Middle English molsh or the German molsch, meaning soft or rotten, a reference to decaying organic matter. As the mulch layer decays, it adds organic matter to the soil, releasing nutrients and improving soil aggregation (the clumping together of soil particles with increased stability and less susceptibility to erosion). This results in better aeration as well as water- and nutrient-holding ability. Less fluctuation in moisture and temperature and more organic matter causes increased microbial activity within the soil, resulting in greater nutrient availability and better plant growth. Finally, the mulch layer acts as a cushion, preventing compaction of heavier soils as we go about our garden chores. It also cushions falling fruit, in many cases preventing bruising.

Temperature Modification A mulch layer insulates the soil below, moderating temperature extremes and preventing sudden temperature swings. By cooling the soil surface during the hot days of summer, mulch

Mulch reduces water and mud splash onto foliage, fruit and vegetables, thereby reducing the spread of soil-borne diseases (such as grey mould or botrytis on strawberries) caused by water splashing onto foliage and fruit.

encourages healthy roots and prevents root injury caused by excessively high soil temperatures. In spring and fall, mulch reduces the freeze-thaw cycles of heavy soils which causes heaving of young plants and root injury to others. Mulch is especially beneficial to evergreens, which lose water through transpiration twelve months of the year. Mulch postpones hard freezing of the soil in fall, so trees can withdraw water from the soil for a longer period. This may reduce winter desiccation and browning, although it may also delay “hardening off” and the onset of dormancy, resulting in winter injury. Mulch keeps the soil cooler in early spring, preventing premature emergence of spring bulbs, which might be nipped by frost.

Reduced Water Splash Mulch absorbs water and almost entirely eliminates mud and water splash. This has the obvious effect of keeping flowers or strawberries clean and more aesthetically pleasing. Less obvi-

Mulch

67

ously, it greatly reduces the spread of soil-borne diseases, caused by fungal spores and bacteria carried by water splashing onto the foliage and fruit.

Design Functions Mulches add subtle colour and texture to our yards. Because they are so diverse, mulches can be used on a wide range of landscapes from the natural to the very formal. They unify planting beds, especially when the plants themselves are young, small and seemingly widely spaced within the bed. They let the world know that, indeed, this is a bed and should be walked around rather than through. Mulching materials such as post peelings and bark chips can also serve as a ground cover for utility areas or be used for garden paths or walkways. Mulch keeps mowers and string trimmers at a safe distance from specimen trees on a lawn, protecting the tree trunks from damage caused by overzealous operators. Shredded post peelings are an ideal mulch for perennials, conserving moisture and preventing weed seed germination.

It is more visually pleasing to use coarser mulches around larger plants and finer mulches around smaller plants.

Applying and Maintaining Mulch Preparation Prior to applying any mulch, ensure that the area is relatively smooth and weed free, especially of perennial weeds such as dandelion, thistle and perennial grasses. A mulch layer of 10 cm (4 in.) will not kill these weeds. Eliminate weeds through continuous cultivation or solarization (described in chapter 6).

When to Mulch Mulch can be applied at almost any time through the growing season when it is available. Although the majority of mulches are maintained on a permanent basis, there are some instances where mulches are seasonal. A summer mulch is applied to annual beds and vegetable gardens once the soil has warmed to about 20°C (68°F) and root growth is active. Its main function is to suppress weeds and conserve water. At the end of the growing season, it is either Mulch keeps lawn mowers and string trimmers at a safe distance from specimen trees on a lawn, protecting the trunks from damage caused by overzealous operators.

68

Creating the Prairie Xeriscape

composted elsewhere or incorporated into the soil. A winter mulch is used to protect tender perennial plants from temperature variations through the winter as well as from drying winter winds. It is applied over semi-hardy plants such as strawberries and tea roses just prior to freeze-up. It is removed in

Problems with mulch There are problems associated with mulch, but not as many as we might imagine. As Kathleen K. Meserve observed in an article written over forty years ago, “in the case of mulch, the price is mice.” Theoretically, many mulches provide an excellent home in which mice can procreate and raise families. Most damage occurs under the snow in winter when other food supplies are limited. The mice may girdle the bark and cambium layer of trees and shrubs. Yet in over three decades of mulching on five acres, I have not noticed an increased rodent problem. Two resident cats have them thoroughly under control. Fire is another potential hazard in extensively mulched beds, particularly if using straw, evergreen needles or cones or peat moss. A “No Smoking” sign is your best prevention.

Contrary to what one might think, coarse mulches actually discourage slugs. By rasping the slug’s tender body parts, these mulches cause dehydration and death.

vegetable garden, make a concerted effort to get

Fresh sawdust, straw or grass clippings may

rid of them before mulching. (Not an easy task!)

cause a temporary nitrogen deficiency because

If the mulch layer is too deep‚ over 10 or

the soil bacteria that break down these prod-

12 cm (4–5 in.)‚ it may cause oxygen depletion

ucts use nitrogen as a source of energy. Once

in the soil atmosphere. This is more likely to

the mulch is decayed, nitrogen is again released

affect shallow-rooted trees in poorly drained

for plant use. My own experience with using

or heavy soils that are prone to waterlogging.

these materials as a mulch is that they break

The use of mulch on poorly drained sites may

down very slowly under our mostly arid prairie

worsen the problem. Correcting drainage prob-

conditions and seldom if ever cause a nitrogen

lems, developing berms or using the area as a

deficiency. To be on the safe side, you may wish

bog garden or water catchment area are alter-

to spread corn gluten meal or alfalfa pellets on

natives to consider.

the soil surface prior to applying the mulch.

Fine-textured mulches like peat moss can

Hardwood chips from deciduous trees decom-

wick moisture from the soil. They should only

pose more slowly than straw, reducing the

be used as a cosmetic dressing over materials

possibility of a nitrogen deficiency.

such as grass clippings. Applied in this manner,

Slugs prefer a dark, moist, cool environment

they will not draw moisture from the soil below.

and life under many mulches would seem an

Acidification is usually not a problem on our

ideal habitat. Yet contrary to what we might

alkaline soils. It is an urban myth that a mulch

initially assume, the coarse texture of many

of evergreen needles and cones will acidify the

mulches actually reduces slug populations by

soil, preventing the growth of nearby plants.

rasping and dehydrating their bodies. If slugs

Our prairie soils are mostly alkaline and very

have been a problem in your flower beds or

well “buffered” to prevent pH change.

Mulch

69

spring once plant growth resumes, often being placed on the soil around these plants to conserve moisture, control weeds and prevent mud splash onto flowers or fruit during the growing season.

How Deep? The depth and evenness of the mulch layer is critical. A layer of 10 cm (4 in.) is ideal. Less than this depth will not work! A more shallow layer may conserve some water and mitigate some temperature change, but it will not suppress weeds. It is much better to mulch a smaller area to the recommended depth than to mulch a larger area at a shallow depth and be disappointed with the results. A depth greater than 12.5 to 15 cm (5–6 in.) may inhibit gas exchange between the soil atmosphere and the air above, resulting in oxygen depletion and injury to plant roots. More is not necessarily better! One cubic metre (1 yd3) of most materials, spread 10 cm (4 in.) deep, will cover about 7.5 m2 (80 ft2). Apply mulch carefully around low herbaceous plants, taking care not to smother them. Keep the mulch about 15 to 20 cm (6–8 in.) away from the trunks of trees.

Water and Mulch Before applying mulch, ensure that the plants within the bed are watered to a depth of 30 to 45 cm (12-18 in.) depending on the depth of their feeder roots. Apply the mulch layer and water again so that the mulch is thoroughly moist. Deeper but less frequent watering is the key.

Mulches should be free of weeds, harmful insects, disease or materials toxic to plants (and pets). If they are locally available, free or of low cost, easily applied and not easily blown by wind, so much the better.

Mulch Renewal Planting beds that are permanently mulched will need topping up with a few additional centimetres of mulch every few years. The timing of this will depend on the type, depth and durability of the mulch used. All organic mulches will eventually decay, adding nutrients and organic matter to the soil below. Unless the bed is to be totally renovated, new mulch is simply placed on top of the original layer. The old mulch is not incorporated into the soil.

Types of Mulches What makes a good mulch? Some of the characteristics of good mulches are local availability, low or no cost and ease of application. It also helps if they are not easily blown about by wind and are free of weeds, harmful insects, disease or materials toxic to plants. Many mulches are by-products of local industries and might

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Creating the Prairie Xeriscape

otherwise end up in the landfill. Their availability varies from one geographic area to another. While sea hay, spent hops and cocoa hulls are not readily available in the prairie region, we still have much to choose from. Grass clippings are free for the taking, as are leaves. Post peelings (waste material in the production of fence posts) generally involve the cost of transportation. Decorative bark is mostly shipped into the prairies and is therefore more expensive.

Organic Mulches Grass Clippings

Grass clippings are the universal mulch: readily available, free and fairly easy to apply. Commonly heard objections to their use include their smell, the introduction of grass into planting beds, 2,4-D contamination and appearance. If used as soon as they are cut, there is no smell associated with grass clippings. When left in plastic bags, they heat and begin to decompose anaerobically without oxygen, in much the

Selecting a mulch Annual flower beds Grass clippings overlaid with coarse peat moss, all of which are incorporated into the soil at the end of the growing season

Perennial beds Grass clippings overlaid with coarse peat moss, chopped or shredded post peelings

Tree and shrub beds Wood chips, coarse bark, evergreen needles and cones, flax shives, post peelings

Vegetable gardens Plastic, straw, grass clippings, biodegradable films

same way as silage and with much the same smell. Although it is often recommended that they be allowed to dry on cement surfaces in 2.5 cm (1 in.) layers prior to use, this is not necessary. If lawns are mowed when the grass is under 10 cm (4 in.) in height, no lawn grass seeds should be introduced. What may be introduced is annual bluegrass (Poa annua), which flowers and produces seed at very low heights. It is considered a weed and is able to colonize lawns and flower beds. By watering deeply but less frequently and overseeding bare patches in your lawn with recommended cultivars in early spring, you can control annual bluegrass in your lawn. If you’re using clippings from a lawn to which 2,4-D or other herbicides have been applied, these clippings should be composted for three mowings after the application. They may then be safely used as mulch, as 2,4-D breaks down within thirty days after application under summer conditions. Apply grass clippings loosely to a depth of 10 cm (4 in.). If you find the appearance of grass clippings on flower beds displeasing, top-dress with a few centimetres (1 in.) of coarse peat moss. Remember, it is the grass clippings that are doing the work. The thin layer of peat moss is merely cosmetic. Coarse Sphagnum Peat Moss

Peat moss is partially decayed sphagnum moss from northern peat bogs. It can be costly and coarser grades may be difficult to

Grass clippings are universally available and free. Use them as a mulch where appearance is not important such as vegetable and fruit gardens. If you find their appearance displeasing on flower beds, top-dress them with a few centimetres (1 in.) of coarse peat moss.

obtain, but it is excellent when used as a thin top dressing over

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71

grass clippings in annual or perennial flower beds. Peat moss is Elm chips as mulch

attractive, lightweight and weed- and insect-free. It is best moist-

Dutch elm disease is caused by a fungus

ened prior to spreading and wetted again afterwards. If allowed

that is spread from one tree to another by elm bark beetles. In order for the elm bark beetle to lay its eggs, branches must be dead or dying and have their bark intact. “Brood galleries” where eggs are laid are tunnelled immediately under the bark.

to dry out completely, it may initially resist rewetting. A 100 dm3 (3.8 ft3) bale will cover 50 m2 (150 ft2) to a 2.5 cm (1 in) depth. Shredded Bark or Post Peelings

Post peelings are a by-product of fence posts. Posts are run through a debarker, which removes the bark in thick strips.

Elm bark beetles find elm trees by smell.

Peelings are low cost but may be manufactured a long way from

They will be attracted to chipped elm wood

your garden and transportation is expensive. They are coarse-

and may hover around it, but as long as the

textured, suitable for tree and shrub beds, garden paths and

chips are small, it is highly unlikely that they

utility areas. They have an attractive colour and smell and are

will be able to raise young on elm chipper

slow to break down. Some have been shredded to make them

debris used as mulch.

finer textured and more suitable to perennial and mixed borders.

Check local regulations prior to using elm chips as mulch. In Manitoba, it is recommended that elm chips not be used in areas where Dutch elm disease is a problem because of concerns about attracting the beetles into these areas. In Saskatchewan, elm bark chips must be burned or buried

Once applied to the soil surface, the pieces hold together and do not blow, allow free water percolation and resist compaction. Decorative Bark

This is a more chunky material, usually brownish red in colour and dried prior to bagging. It is produced specifically for the landscape industry and can be expensive if used over large

and cannot be used as mulch. In Alberta,

areas. Decorative bark resists compaction and allows free water

their use is legal if the chips are under 2.5 cm

percolation. Until the area is irrigated, it may blow. It is used in

(1 in.) in diameter.

tree-shrub beds where appearance is important. Chipper Debris

For many decades, material pruned from trees was sent to landfills. Because of the escalating cost of maintaining these sites and the associated increased user fees, most tree prunings are now being chipped and either composted or used as mulch. Chips may be free for the hauling from municipal pruning crews, utility companies (which routinely prune under their lines or along easements) or private pruning companies. Transportation costs are extra. The texture, composition and attractiveness of wood chips varies depending on the species and size of the material being pruned and the time of year. In summer, chipper debris includes leaves. In winter it does not. Christmas trees are often chipped at municipal sites and these mulches will likely include tinsel! If a pruning company has been drilling out stumps, soil may be Post peelings are an ideal and long lasting mulch, allowing free water percolation, resisting compaction and seldom blowing, but transportation costs can make them expensive.

included. This is not a good thing, as weed seeds that blow onto the soil may readily colonize in the mulch. Chipper debris is used in tree-shrub beds as well as shelterbelt plantings. As a mulch, it is coarse-textured and allows free water percolation; the pieces often interlock, reducing blowing or scattering. It weathers to a grey colour over time. Durability is related

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Creating the Prairie Xeriscape

to the size of the chips and the depth of application, but it generally lasts three to seven years under dry prairie conditions. Sawdust and Wood Shavings

Sawdust and wood shavings may be obtained free from sawmills, lumber mills, retail lumber stores and local high school or community college shop teachers. They are widely available and used to mulch small fruit, trees, shrubs, vegetables, row crops, hardy spring bulbs such as tulips and daffodils and gladioli. They compact and decompose relatively quickly. With minimal soil contact, breakdown is slow and nitrogen depletion is generally not a problem. They improve the soil as they decompose. If you think nitrogen depletion may be a problem, apply a light sprinkling of corn gluten meal or alfalfa pellets prior to spreading the sawdust or wood shavings. Evergreen Needles and Cones

There is a pervasive and perverse tendency to attempt to grow lawns under evergreens. Lower branches are removed, mutilating once graceful conifers, to allow headspace for the mower operator, topsoil is brought in and still the grass fails. Grass was never meant to grow under evergreens. Think about our coniferous forests: the forest floor is carpeted with

Chunky and usually brownish red in colour, decorative bark is lightweight and may blow until irrigated. It’s attractive, allows free water percolation and resists compaction.

cones and needles, mulching the soil, retaining moisture and supplying nutrients. Why not emulate nature and allow your own evergreens to grow with lower branches intact and a natural mulch of their own cones and needles? If the soil surface under your evergreens is bare, begin by covering it with any of the recommended mulches. Recycled chipped Christmas trees are a good start. Then let the cones and needles fall! They look good, do not compact, allow free water percolation and decompose slowly. Straw

Wheat, rye, oat, barley and flax straw are widely available and inexpensive. They are used with coarse-textured plants or where appearance is not important: small bush fruits, orchards, vegetables, shelterbelts and newly planted trees. Straw allows good water percolation, conserves water and cools the soil, buffering it from day-night temperature changes. It is often used as a winter mulch to protect strawberries and tender roses. If shredded, it is fine for use on flower beds. Flax straw is particularly durable and will need renewal less often than other straws. Hay is generally considered more weedy, but old hay is often used on shelterbelts to conserve moisture. Problems associated with the use of straw include mice,

Imitate nature! Grass was never meant to grow under evergreens. Leave the lower branches of your spruce intact and simply let the cones and needles fall.

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73

increased fire risk, the introduction of grain as weeds and sometimes a temporary nitrogen depletion. Flax Shives

Flax shives are a by-product of the flax straw used in the production of paper. Shives form a dense mat, preventing weed germination by light exclusion. They are an excellent mulch for perennial beds and tree-shrub borders. Apply flax shives to a depth of 10 cm (4 in.), keeping them 15 cm (6 in.) away from tree trunks to discourage rodent damage to trunks. Mowed Leaves

Bagged every autumn by zealous gardeners, leaves are a readily available mulch that all too often ends up in the landfill. If leaves are falling thickly over your lawn, simply shred them with your lawn mower and rake them onto adjacent tree and shrub beds, the vegetable garden, annual flower beds and perennial borders to a depth of 20 to 25 cm (8–10 in.). By spring they will have all but disappeared. Newspapers Flax shives, a by-product of flax straw used in the production of paper, forms a dense mat, preventing weed germination and conserving water.

Although less aesthetically pleasing, heavy layers of newspapers have been used as mulch where appearance doesn’t matter. They should be wetted or weighed down with rocks or boards to keep them in place.

Inorganic Mulches Inorganic mulches, such as plastic sheeting, landscape cloth and rocks, are more durable than organic mulches, but are usually manufactured from non-renewable materials and do not benefit the soil. Organic mulches are preferred and recommended. Plastic

Plastic (polyethylene), usually available in rolls, is among the cheapest of the inorganic mulches. In landscape applications it is almost always covered with a more attractive organic mulch to protect it from ultraviolet light and wear and tear. Ultraviolet light resistant products are recommended. Plastic mulches control weeds and allow for air exchange between the soil atmosphere and the air above, but only permit water penetration through the openings of planting holes. Plants mulched with plastic should be irrigated with a drip system. Tomatoes, peppers, eggplants, cucumbers, squash, melon An excellent and long-lasting mulch for perennial beds and tree-shrub borders, flax shives should be applied to a depth of 10 cm (4 in.).

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Creating the Prairie Xeriscape

and sweet corn respond well to all types of plastic mulch, usually producing earlier crops with higher yields, cleaner fruit and less disease. Clear plastic mulches create a greenhouse effect, resulting

Mulching new shelterbelts: A special application For many years, shelterbelts were kept weed

they conserve moisture, prevent soil erosion

free using tillage, either by machinery or, early

and prevent weed seeds from germinating by

on, by hand hoeing. Both are labour intensive

blocking light. Because they are impermeable

and are often carried out too close to the young

to water, they are best used in conjunction with

trees and at too great a depth. The net result is

drip irrigation.

damaged roots, suckering and excessive evaporation due to the depth of tillage.

Areas to be planted should be level, weed free and without clods so the plastic can be

Using mulch to control weeds in newly

laid flat. Available in 450 m (1,500 ft) rolls, they

planted shelterbelts is a better alternative. It

usually contain an ultraviolet inhibitor and

is more environmentally friendly and has the

are laid in place over the newly planted trees

added benefits of trapping moisture while min-

with a mechanical applicator. The tree seed-

imizing evaporation and reducing wind erosion

lings are then pulled through slits cut in the

and soil crusting.

plastic. Seedlings should not be allowed to rub

Mulches recommended for shelterbelt trees

against the plastic. The plastic is pinned to the

include individual sheet mulches, roll mulches,

soil at each tree with special staples or a rock.

wood chips and flax shives.

The edges of the plastic sheet are secured

Individual sheet mulches

Individual sheet mulches are porous, allow

with soil rolled onto them by the mechanical applicator.

water to reach the soil and are effective in con-

Permeable woven plastic rolls of 100 m

trolling weeds. Lightweight and easy to apply,

(300 ft) and 150 m (500 ft) are also available but

most contain ultraviolet inhibitors and last

are more expensive. They contain ultraviolet

about three years. By that time, the trees are

inhibitors, are very durable and are permeable

taller than surrounding weeds and are able to

to water. They are applied the same way as the

compete for light, space, nutrients and moisture.

plastic rolls.

The sheets are made of porous plastic, fabric

Wood chips or chipper debris

pad, straw glued to paper or recycled paper coat-

Wood chips prevent weed germination by

ed with wax. They vary in size, but a minimum

excluding light, maintain a cool soil tempera-

size of 0.6 x 0.6 m (2 x 2 ft) is recommended. Mow

ture and reduce water evaporation from the

weeds prior to planting trees to reduce rodent

soil. They should be applied to a depth of 10

habitat and make tree planting and mulch

cm (4 in.) and kept 15 cm (6 in.) from the tree

application easier. Apply the mulch as soon as

trunks to discourage rodent damage.

the young trees are planted. Secure with rocks

Flax shives

or special mulch staples. Using clods of soil is

Flax shives are a by-product of flax straw used

not recommended because they eventually

in the production of paper. They form a dense

crumble, providing a site for weed colonization.

mat, preventing weed germination by light

Roll mulches

exclusion and conserve soil moisture. Apply to

Black plastic roll mulches are used for shelter-

a depth of 10 cm (4 in.), keeping shives 15 cm

belt and wildlife plantings. Like sheet mulches,

(6 in.) from tree trunks.

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75

in very high soil temperatures during hot, sunny weather. Some degree of soil warming promotes root growth of heat-loving plants, but during prolonged periods of extremely hot weather, soil temperatures under clear plastic mulch may rise high enough to harm plants. Black plastic is less effective than clear plastic for soil warming, but it has the advantage of controlling weed growth. It is laid over level, weed-free soil. Slits are made at appropriate intervals and vegetable seedlings planted into the soil through the slits. Drip irrigation lines are laid with emitters serving each plant. Biodegradable mulches, made from products such as starch film, are intended for vegetable gardens.

Although water does not penetrate it, soil moisture below the plastic is retained. Newer biodegradable mulches, intended for vegetable gardens and made of products such as starch films, are also available. Landscape Cloth

These fabrics are made of woven or bonded polypropylene or nonwoven polyester. Woven fabrics allow water, fertilizer and air to penetrate, reduce surface evaporation and block weeds. Stronger and more durable than plastic sheeting, they are also more costly. Like plastic, they are usually covered with a decorative organic mulch when used in a landscape situation. Nonwoven polyester fabrics last longer and are more resistant to degradation than polypropylene, but are also more expensive. Before applying these fabrics, grade the area so that it is level and remove any weeds. Lay the fabric over the soil and cut slits where plants are to be placed. Once planted, place a minimum of 5 cm (2 in.) of organic mulch over the fabric to improve its appearance, reduce wear and protect it from ultraviolet light. By applying 10 cm (4 in.) of organic mulch, there is no need for Organic mulches, applied to a depth of 10 cm (4 in.) are effective, attractive, allow for the free percolation of water, and eliminate the need for landscape cloth.

landscape cloth. Rocks and Gravel

Rocks and gravel are available in many sizes and colours. Larger rocks may be used in rock gardens or as a structural part of the landscape and rounded, river-washed cobbles make attractive dry stream beds. The use of crushed rock and gravel as mulch, however, is not recommended. Although long-lasting, they are

Xeriscape is not “Zeroscape”

costly in terms of the energy input required to mine, crush and

Rocks do not improve the soil and smaller

transport them and they should be considered a non-renewable

rock aggregates are more mobile than gen-

resource. They are often used over plastic sheeting, but if weeds

erally believed, moving with foot traffic as

germinate in soil blown onto the rocks, removing them is hard

well as lawn mowers. Rocks are often used in xeriscaping, but their presence is more indicative of a “zeroscape” than a “xeriscape.”

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Creating the Prairie Xeriscape

on the knuckles. They reflect heat and light, raising temperatures and providing a rather inhospitable microclimate for most plants as well as people.

CHAPTER 6

Lawns Less Is Better Lawns are among our landscape’s biggest consumers of water. To look good, our traditional lawn grasses need more water than is available through natural precipitation on the prairies. It is estimated that 50 percent of summer household water is used on the landscape and the vast majority of this is applied to lawns. Historically, lawns were once natural meadows used as public space or “commons” in towns and villages in Europe – places where livestock could be grazed and fairs and meetings held. In the eighteenth and nineteenth centuries, lawns surrounded the homes of rural gentry and were cropped short by sheep. The invention of the lawn mower in the 1830s made lawns manageable even for the urban middle class. Since World War II and the advent of chemical pesticides, lawns have become almost a suburban status symbol. They occupy the largest amount of space in our landscape – a reflection of North Americans’ outdated concept of space and low population – and encourage a quest for perfection that motivates some of us to over-apply water, fertilizer and pesticides in their care.

Benefits of Lawns Lawns are resilient, comfortable and safe places for play and leisure. As a design component in the landscape, they serve as “negative space,” unifying the yard and accenting flower beds and mixed borders. Lawns reduce dust, glare and air pollution and help control erosion and runoff. Grass also lowers summer air and surface temperatures through transpiration. As water inside the plant evaporates through the tiny openings in the leaf surface called

Lawns provide the “negative space” that emphasizes flower beds, mixed borders and specimen trees in our landscapes.

stomates, it changes to vapour. Every gram of water that does

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77

this extracts 540 calories of heat from the plant’s surface, cooling the atmosphere around it. Lawns provide a perception of space and openness that is dear to the prairie dweller. That long sward of green lawn is psychologically therapeutic, giving us a sense of quiet, calm and well-being.

The Downside Conventional lawns must be watered. The costs involved in watering include the cost of the water itself as well as the equipment used to deliver it. This equipment may vary from a hose with a manually attached sprinkler to an elaborate automated underground irrigation system. Lawns are costly to establish and to maintain over the many decades of their life. Mowing involves equipment and Conventional lawns are labour intensive and must be mowed, watered and fertilized.

its maintenance, as well as gas and oil or electricity. Fertilizers and pesticides are generally applied, often at higher rates than needed. Nutrients and chemicals applied to the lawn may end up polluting waterways and aquifers. Finally, we invest a lot of time in the establishment and maintenance of our lawns, but few of us consider mowing a labour of love.

Rethinking Lawns Function Take a second look at the amount of turf you have and consider what you actually do with it. Survey the lawn areas of your landscape. What is the function of each area? How is each area used by your household?

The intimate Some of your lawn area is indeed used for leisure. You sit on it or lie on it, a toddler toddles on it, a teenager sunbathes. Your contact is generally of an intimate nature. This area of lawn should be left as conventional lawn, but perhaps redesigned to the pattern of your irrigation system so as to conserve water. A soft, resilient surface, lawns are a comfortable and safe place for play and leisure. A toddler can toddle, a teenager sunbath, and we can walk barefoot on them. And Boris the cat can enjoy quality outdoor time.

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Creating the Prairie Xeriscape

Some parts of your lawn may be so intensively used that they may be better converted to “hard surfaces” such as decks or patios. These can withstand heavy amounts of human traffic and need no water, fertilizer or mowing. Such areas are usually immediately adjacent to the house. Could some of your lawn be converted to hard surface area?

The hardly-used-at-all Other areas of your lawn are there simply by default. They are seldom walked on unless you are behind a mower. These are usually peripheral to the area of more intense use and may consist of odd strips or difficult-to-reach corners. Long, narrow areas between the street and the sidewalk or between the sidewalk and the driveway are almost never used as lawn. These are easily replaced with low maintenance, drought-tolerant ground covers.

The visual sward Many areas of a conventional lawn are seen but not actually used. Their function is almost purely visual. Entire front lawns could easily be converted to beds of drought-tolerant ground covers, flowers, shrubs and ornamental grasses to provide colour, texture and form. They would become much more interesting and, once established, involve less maintenance. In rural areas, on farms and acreages, large areas of lawn are there only as a visual sward of green. They are usually composed of rough bunch-type grasses and were never intended to be walked or sat upon. They are never watered or fertilized and are mowed only as needed. These may be left as they are or overseeded with more recently developed low-maintenance grass cultivars. They may be visually broken up by mass plant-

A lawn under a tree is difficult to mow. Why not replace it with a low maintenance, drought tolerant ground cover? Here the soft grey foliage of snow-in-summer (Cerastium tomentosum) echoes the grey foliage of the Russian olive above it.

ings of drought-tolerant perennials, ornamental grasses or tree-shrub borders.

Options If your household makes little or no use of the existing lawn, there are several options to consider. You may want to retain a conventional lawn but reduce its area to that which is actually used. Reshape the portion of the lawn that is retained so that it conforms to the pattern of a standard sprinkler, thereby reducing water wastage. You may refrain from irrigating entirely, although accepting summer browning involves a greater tolerance for seasonal changes than most of us have. It may necessitate developing a fairly thick skin to resist pressure from more conventional neighbours. Alternatively, the lawn can be eliminated entirely.

Retain, but... Size and location

How much lawn does your household use as lawn? Why not replace that which is hardly used at all with ground covers, flower beds or mixed borders that require less work and fewer inputs?

Consider the size and location of your existing lawn. It should be placed where it will be used as a lawn. This may be close to

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79

Removing an existing lawn If your lawn is in poor condition because of

assurance that the kill will be fully effective.

poor site preparation or you decide to use a

Some subsequent weeding will be necessary.

more drought-tolerant species, you must first remove the existing lawn. Some methods are more labour intensive than others. Some are (almost!) instant, while others involve an entire growing season. Regardless of which method you use, try to retain and incorporate existing organic matter.

Physical removal Sod is cut to a depth of 5 cm (2 in.) with a mechanical sod cutter or a sharp spade, removed and either composted or used elsewhere. The disadvantages of this method are that it is very labour intensive and that organic matter – the old turf – is permanently removed from the site. Because the finished grade is reduced by several centimetres (a few inches), topsoil will have to be added, costing additional time, labour and expense.

Turning sod upside-down

80

Cultivation Repeated rototilling while keeping the area fallow for a growing season retains the old sod as organic matter but takes time. It also breaks down soil structure and encourages the loss of organic matter.

Soil solarization Mow the lawn and then water it deeply to moisten the soil (moist soil conducts heat more readily than dry soil) and encourage fast, succulent growth. Then cover the area with black plastic, anchoring its edges with rocks, bricks or clods of earth to hold it tightly against the soil. Leave the plastic in place until the grass is dead, about three to six weeks. The black plastic prevents the grass from photosynthesizing. The intense heat generated underneath the plastic kills vegetation. This method works best during the heat of the summer when daytime

Turning the sod upside-down in place retains

temperatures are above 30°C (85°F) for a week

organic matter but is labour intensive. It takes

or two. It is less effective during cooler spring

several weeks to kill the sod and there is no

and fall weather.

Creating the Prairie Xeriscape

a patio, deck or back door. It may be under a tree that provides shade. It may be next to a swimming pool, swing set or sandbox – wherever the members of your household sit, lie down and recreate, where they go barefoot and are actually in intimate contact with the lawn. The size of your lawn will depend on household use. Observing your family at play and at leisure over a period of several weeks during the summer will determine this.

Shape Regardless of whether the sprinkler head that delivers water to your lawn is part of an underground system or attached to the end of the hose, consider the shape of its delivery pattern. To use water more efficiently, shape your lawn to coincide with the shape in which your water is delivered (or how it will be delivered if you are installing a new irrigation system). Outline the shape of your proposed lawn with a garden hose. Then set up the sprinkler you will be using and modify the shape of the lawn until it coincides with the delivery pattern of your sprinkler. Round, square and oval lawn areas are generally more

Fleeceflower or bistorta (Persicaria bistorta), best in full sun, provides dense basal foliage and bright pink bottle brush flowers.

conserving of water. The more rectangular the lawn area, the less efficient is the irrigation and the greater the loss of water. Lawns with the same area need increasingly more water as their perimeter increases. This does not mean that the lawn itself must be square or circular. Adjacent flower and shrub beds can soften the geometry while still ensuring that the area as a whole is water efficient.

Replace With... Drought-tolerant alternatives Small areas of lawn in odd corners and long, narrow grassed strips are easily replaced with drought-tolerant annuals, perennials, ornamental grasses and ground covers. Larger areas of lawn can be replaced with layered, mixed borders. (For ideas on the development of such borders, consult chapter 2; for selection of plants, see section 2.) Lawns adjacent to large expanses of reflective aluminum or white siding, white stucco or cement are particularly susceptible to drought stress caused by reflected heat and light. Nor are these spaces conducive to leisure activities. They are better planted with drought-tolerant ground covers.

‘Calgary Carpet’ juniper forms a bright green, evergreen ground cover for full sun or partial shade.

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81 81

Hard surfaces Some areas of a conventional lawn can be replaced with hard surfaces. Although wooden decks require upkeep, they remain a popular choice. Patios should also be considered. Crushed gravel, sand or organic mulches such as post peelings can be used for paths. Avoid large areas of cement or asphalt, which absorb heat or reflect light and aggravate drought conditions.

Drought-tolerant grasses Substitute drought-tolerant grasses for those large expanses of conventional lawn that are seen from a distance but seldom used. Drought-tolerant grasses are usually bunch-type grasses, which form small clumps with spaces between. These spaces are less evident if the lawn is seeded thickly and mowed regularly to 15 cm (6 in.). In smaller urban yards this may not be easy, since many conventional mowers cut at a maximum height of 10 cm (4 in.) The ride-on mowers used by most rural dwellers have a higher maximum cutting height. This multi-level deck provides lots of people space and easy access to the lawn. Note the tree that will one day provide shade from afternoon sun.

Ground covers made easy If you plan to replace existing lawn areas

In large rural yards the conventional lawn and the “distant” lawn can be separated by gently curving borders of massed drought-tolerant perennials or ornamental grasses (see chapter 2). The difference between the two types of lawns is not likely to be noticed, at least not by “a man riding by on a fast horse.”

Water-Conserving Practices Establishing a New Lawn

with ground covers such as junipers or day-

The vast majority of lawn problems can be traced to poor soil

lilies, simply dig generous-sized planting

preparation during the establishment of the lawn. Most of these

holes into the existing sod. Amend the soil

are related to insufficient topsoil or organic matter, poor grading

within these planting holes and water well

or persistent perennial weeds.

after planting. Apply a mulch layer of 10 to 15 cm (4–6 in.) over the remaining lawn. The mulch layer will kill most (but not necessarily all) of the grass.

The importance of proper site and soil preparation cannot be overemphasized. The benefits of good site preparation include water conservation and lower maintenance inputs – including your time – during the lifetime of the lawn. If you are establishing or renovating a small area of lawn using grasses that will be irrigated, the following water-conserving practices are particularly important. If you are dealing with large areas of lawn that will not be irrigated, some of these practices will not be practical.

Removal of debris If the site has been the scene of recent construction, remove (rather than bury) all building materials. When simply covered, these materials may cause problems with water percolation or

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Creating the Prairie Xeriscape

toxicity to plants. They may also lead to subsequent sinking and settling of the soil and disturbance of the final grade. They

Overseeding rather than renovating

may limit the depth of rooting of the lawn, causing heat- and

Sometimes it is easier to overseed an ex-

drought-stress.

Weed control

isting lawn with a more drought-tolerant species rather than totally renovating it. This procedure involves mowing the lawn

Weeds rob lawns of moisture and nutrients, shade and crowd

as short as possible, removing thatch and

out lawn grass and may harbour diseases and insects. Purchased

other debris, top-dressing with 1 cm (½ in.)

topsoil should have been screened to remove rhizomes of quack

of soil well amended with organic matter

grass and other perennial weeds. If you are establishing a lawn

and overseeding at up to twice the normal

on existing soil, there are several options for the control of perennial weeds. All of these are more effective if you first water the soil well to encourage the emergence and growth of weed seeds, roots or rhizomes present within the soil. After the weeds have emerged but while they are still small and have not gone to seed, you can either solarize or till.

seeding rate with a drought-tolerant grass species or mix. The grass seed is raked in, rolled so that it is in firm contact with the soil and kept moist for several weeks. This is not a foolproof method and germination and establishment is seldom 100 percent. Because watering also encourages the

To solarize, cover the area with black plastic for about six

growth of the original sod, the new grass

weeks during the heat of midsummer. The excessive heat gener-

may have difficulty rooting through the old

ated through this process (called solarization) kills almost all

sod and into the soil below.

vegetation. Once weeds are dead, incorporate them into the soil. Tilling involves hand digging or rototilling the area three or four times during the growing season. Water well between tillings to encourage all perennial weed rhizomes or seeds to grow. Avoid cultivation when the soil is wet.

Grading Prior to spreading topsoil, establish the final grade of the subsoil. Soil should be sloped at about 2 degrees away from buildings, driveways, sidewalks and patios. This ensures that excess rain or irrigation water flows away from foundations and walkways and that ice does not form on hard surfaces. Steep slopes are awkward for sitting and other forms of human leisure and are difficult surfaces on which to establish a lawn. Mowing, fertilizing, watering and weeding are also difficult or dangerous on slopes. If slopes cannot be eliminated, it is better that the area be terraced and planted with alternative groundcover varieties. If the lawn is to be sodded, the final grade, once topsoil has been spread, should be 2 cm (3/4 in.) lower than adjacent hard surfaces so that the sod will be level with sidewalks and driveways.

Topsoil Remove and stockpile existing topsoil prior to establishing the grade. A minimum of 15 cm (6 in.) of topsoil containing at least 5 percent organic matter is recommended. More is almost always

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Seeding versus sodding There are advantages and disadvantages to

If using several species or cultivars, mix

both methods of lawn establishment. Site and

the seeds together prior to spreading. Use a

soil preparation are identical.

cyclone-type bag spreader or a push-type centrifugal or drop spreader. For more uniform

Seeding Seeding offers more choices in the type of grass

need in half, set your spreader at the lowest

to be used. Although cheaper than sodding,

possible setting and spread half of the seed in a

it takes considerably longer and involves much

north-south direction and the other half in an

more labour over an extended establishment

east-west direction. Use a roller to ensure that

period.

the seed is in firm contact with the soil.

Use high-quality seed. Canada No. 1 grass

Care after seeding is critical. Young grass

seed allows only 0.5 percent weed seed on a

seedlings are very sensitive to heat and drought

weight basis and requires that the seed be 85

and should never be allowed to dry out. Even

percent pure and have a germination rate of

moisture is especially critical during hot, dry,

70 percent.

windy weather.

Sow grass seed when conditions are most

Watering seedlings is quite different from

favourable for its germination and least favour-

watering an established lawn. It should be fre-

able for germination of weed seeds. Weed seeds

quent and light, with little pressure and fine

germinate readily in spring when cultivation

droplets. As the root system penetrates deeper,

has brought them close to the soil surface and

so should the depth of irrigation. The frequency

light, moisture and temperature conditions are

of irrigation is gradually decreased as the depth

optimal for their growth. Cool-season grasses

of irrigation is increased.

are best sown in mid to late summer. There is

Mowing stimulates tillering and rhizome

less weed competition and six to eight weeks

production, increasing the density of the

remain for establishment prior to the onset of

lawn. Mow a newly seeded lawn to 7.5 cm

winter. Because natural rainfall is at its lowest

(3 in.) when the grass reaches 11 cm (4.5 in.)

at this time of year, irrigation is usually neces-

in height. By leaving the grass slightly higher,

sary during the establishment period.

you will provide a greater leaf surface area for

Seeding rates are usually given as a range.

food (carbohydrates) manufacture through

Use higher rates if you are unable to water;

photosynthesis and will enhance rooting. It

on slopes, banks or areas prone to erosion; or

is particularly important during the estab-

if you want an established lawn as quickly as

lishment period not to weaken the plants

possible. Denser seeding rates result in thicker

by removing more than one-third of the leaf

lawns sooner. To determine the amount of seed

blade at each mowing. Ensure that the blades

needed, divide the number of square metres

of your lawn mower are sharp. Do not use a

in the area to be seeded by 100 and multiply

newly seeded lawn until after its second or

by the seeding rate. Seeding rates are given by

third mowing.

genus or species later in this chapter.

84

distribution, divide the amount of seed you

Creating the Prairie Xeriscape

Sodding Sod produces an almost instant lawn. It

thirty hours. If left in piles, it is very vulnerable

immediately reduces erosion and runoff and

to heating and drying. Upon delivery, place sod

involves much less fuss and maintenance dur-

in the shade, cover it with a tarp and lay it as

ing establishment than seeding. It is, however,

quickly as possible.

more expensive and your choice of grass is more limited. Site preparation is the same. If slopes and other difficult sites are to be grassed, sod is preferred to seeding.

Rake and moisten the soil just prior to sodding. Do not lay sod on dry, crusted soil. A minimum of 15 cm (6 in.) of topsoil is recommended for sodding. More is better. Begin sodding at a building or sidewalk or

Sodding can be carried out through most of

along a straight line created by a taunt string.

the growing season as long as rooting can occur

Lay the sod in brickwork fashion. Sod should

prior to freeze-up. More water will be needed

be laid perpendicular to slopes, starting at the

during the heat of midsummer. If possible,

bottom and working upward. Roll after laying

select a sod grown in the same soil texture as

to eliminate any unevenness of the soil and to

that in your yard. This will ensure better water

put the sod in firm contact with the soil. Water

percolation and faster root penetration of the

thoroughly, through the sod and 15 cm (6 in.)

sod into the soil.

into the topsoil below. Sod has a very limited

Good-quality sod will have been grown

root system and is very vulnerable to drying

from seed under irrigation. It is dense, weed

out. To quote Dennis McKernan of Olds College

free and holds together when handled. Sod

in Alberta, sod “is a transplanted plant that has

pieces should be uniform in size and thickness.

had most of its roots cut off in the harvest-

Sod less than 2 cm (¾ in.) establishes more

ing process.” If allowed to dry out, sod pieces

quickly than thicker sod. Sod should be har-

contract and leave gaps, which must then be

vested, delivered and laid within twenty-four to

hand-filled with soil, a laborious process.

Sod provides an instant lawn with little fuss or maintenance once it is laid. On the downside, it is more expensive than seed and your choice of species may be more limited.

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85

better. Prior to spreading the topsoil, rototill the subsoil so that differences in soil texture do not form an artificial layer that impedes water percolation or root penetration. Apply half of the topsoil and rototill, then apply the second half and rototill again. The object is to have a gradation between the topsoil and subsoil rather than two distinctly different soil types, which can impede water percolation.

Organic matter Incorporate 6 to 10 cm (2–4 in.) of organic matter – well-rotted manure, compost, peat moss or spent mushroom compost (see chapter 3) – into the topsoil to improve its nutrient and waterholding ability. This is an important practice that can make a big difference to the success or failure of a lawn.

Soak to settle Before seeding or sodding, water the area thoroughly over a few Kentucky bluegrass lawns should be mowed when they reach about 12 cm (4.5 in.) in height, cutting to 7.5 cm (3 in.). Ensure that the mower blades are sharp.

weeks to ensure final settling of the soil and to encourage any remaining weeds to germinate so that they can be controlled before the lawn is seeded or sodded.

Lawn Maintenance from a Xeriscape Perspective The way you subsequently water, mow, fertilize and weed your lawn also makes a difference to water consumption.

Water To maintain a lush, green appearance, conventional Kentucky bluegrass lawns need a minimum of 2.5 cm (1 in.) of water per week in spring and fall and up to 4 cm (1.5 in.) during the heat of summer. If this is not provided by rainfall, it must be supplied through irrigation. Delay watering your lawn until the top several centimetres (few inches) of soil moisture from spring snow melt has dried out. During the growing season, water only when the soil surface has begun to dry out. After each watering, the soil should be moist to a depth of 20 centimetres (8 in.) or more. Ideally Water your lawn only when the soil surface has begun to dry out. After irrigation, the soil should be moist to a depth of 20 cm (8 in.) or more.

this will be several centimetres (a few inches) below the root zone of the lawn. Deep root development is one of the major factors in drought tolerance, regardless of grass species. This is accomplished through deep and thorough soil preparation and deep, infrequent watering. Plants initially absorb water near the soil surface and then at progressively greater depths as water

86

Creating the Prairie Xeriscape

percolates into the soil. Watering deeply but less frequently also discourages warm-season weeds and annual bluegrass,

Too much water

which thrive on shallow but frequent irrigation.

Many lawns receive twice as much water

If you decide to retain a fairly large lawn, separate it into irrigation zones according to water needs. Lawns in the shade of buildings will require less water. Areas requiring more water include those with heavy use and associated wear, those adjacent to large masses of cement or reflective siding and those

as they require. The City of Edmonton recommends 20 to 30 mm (¾-1 in.) of water per week, delivered in larger droplets close to the ground. The amount of water actually received can be determined by a rain gauge as described in chapter 4.

in competition with the root systems of trees. Where turf density is low, there is a greater loss of water from the soil surface through evaporation. Lawns on slopes or banks, especially those with a south- or west-facing exposure, will also require more water, but irrigation may have to be interrupted to prevent runoff.

Lawn Colour Alerts

Irrigation systems may apply water at a faster rate than

Lawn grasses are “colour coded” to indi-

can be absorbed into the soil. The result is runoff onto side-

cate drought-stress, turning from a bright

walks and streets. Time the irrigation cycle so that what is

or dark green to blue grey. “Foot printing”

applied can be absorbed. Heavier clay soils will require an

and colour change indicate a need for wa-

interrupted schedule, with fifteen minutes on and thirty min-

ter. Water before these signs are evident.

utes off, for efficient absorption. Water during the coolest time of the day when winds are calm, usually in the early morning before 7 a.m. Excessive watering after applying fertilizer may cause it to leach below the root zone of the grass and contaminate the water table. Depending on soil type, only 10 mm (1/2 in.) or less of water is needed to bring these products into the root zone where they will be used.

Mowing From a human perspective, we mow our lawns because they are more comfortable to sit on at 7.5 cm (3 in.) than at 30 cm (12 in.). Culturally, our perception of a lawn is a short green sward rather than a hayfield or a meadow. Mowing the lawn makes it thicker because mowing removes hormones in the expanding leaf that would otherwise inhibit additional shoots from being initiated from the crown. However, it is important to understand the relationship between root- and top-growth. Short grass blades have a smaller area capable of photosynthesizing and producing food for the plant. Mowing too short reduces vigour by reducing the ability of the plant to

By using a mulching mower that cuts clippings into smaller pieces and returns them to the lawn, you can reduce fertilizer requirements by as much as 15 percent.

manufacture food. If food manufacture is limited, the root system, which depends on the leaves for its sustenance, will be reduced. As mowing height is lowered, the root mass becomes smaller. A

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small root system limits the plant’s ability to take up water and Organic versus chemical fertilizer: Advantages and disadvantages When you purchase a bag of chemical fertilizer, it’s generally more concentrated, in pellet or granulated form and easy to apply. The percentage of nitrogen, phosphorus

soil nutrients, making it more vulnerable to the stresses of heat, drought, cold or heavy wear. Higher-cut grass is more tolerant of stress, especially during the heat of summer. Older recommendations stated that lawns should be cut to 5 cm (2 in.), with mowing recommended when the lawn reached

and potassium (N,P,K) is written on the la-

7.5 cm (3 in.) in height, thus reducing the blade height by one-

bel. Most are soluble and quickly available

third. More recent recommendations encourage waiting until

for plant use.

the lawn is about 12 cm (4.5 in.) in height and cutting to 7.5 cm

But there are disadvantages to chemical fertilizers. If over-applied they can “burn”

(3 in.). You are still only removing one-third of the grass blade while obtaining all of the benefits.

your lawn. They are easily leached into the

Taller grass shades and cools the soil surface, reducing mois-

groundwater and may raise the salt level of

ture loss caused by evaporation. The height of the grass, coupled

your soil to the point where it is toxic. As

with its increased density, reduces weed seed germination,

well, they add no organic matter to the soil. Organic fertilizers also have both advantages and disadvantages. They are bulky to handle and may be awkward to apply. Their precise analysis may be unknown. They may take several weeks to become “avail-

which conserves still more water and reduces herbicide use. Grass grown in the shade will especially benefit from a higher cut because the increased leaf area compensates for the lack of direct sunlight falling on the leaf surface. Keep the blades of the mower sharp. Dull blades produce a

able” for plant use. But they benefit the soil

ragged cut, increasing the cut surface area of the leaf and asso-

in ways that chemical nutrients never can,

ciated moisture loss. The cut surface turns an unsightly grey

adding organic matter that improves its

green. The opportunity for disease entry is also increased.

workability as well as its water- and nutrientholding ability. What’s more, organic fertilizers provide a hospitable environment for the many beneficial microorganisms that help fight off plant diseases.

Mowing patterns should be changed regularly to reduce wear patterns.

Fertilizers and Herbicides Poor fertility leads to low lawn density and more weeds. Increasing fertility and mowing height produces more shade on the soil surface, reducing weed seed germination. The overuse of chemical fertilizers, however, may lead to excessive growth, fertilizer “burn” and the leaching of nutrients with associated water contamination. Heavy nitrogen applications stimulate shoot growth at the expense of the root system, leaving the root system less capable of supplying water and dissolved nutrients to the top growth. Grass is then more vulnerable to heat- and drought-stress and accompanying wilt. Lawn grasses grown with deep but less frequent irrigation and lower nitrogen levels are less prone to wilting. Among the organic nutrients recommended for lawns are compost, composted manure, alfalfa pellets or meal and

Alfalfa pellets are an organic fertilizer containing 3 percent nitrogen,1 percent phosphorus, and 2 percent potassium.

88

Creating the Prairie Xeriscape

corn gluten meal. Lawn clippings are also a source of nutrients. Fertilizer is used to compensate for wear – use of the lawn – and tear – mowing of the lawn. Each mowing removes nutrients. Returning clippings to the lawn recycles nutrients,

reducing fertilizer requirements by as much as 15 percent and reducing nitrogen inputs required by as much as 0.5 kg/100 m2(1 lb/1,000 ft2) per year. Use a mulching mower to cut clippings into smaller pieces, which decompose faster and are less likely to contribute to a thick thatch layer. Over time, as clippings are recycled within the lawn, fertilizer requirements will continue to decrease somewhat. Restrictions on the use of herbicides for urban yards are becoming more common due to growing concerns about their effect on the environment and human health. Even if there is no ban in your community, consider using some of the newly introduced organic herbicide alternatives. Corn gluten meal has no effect on established weeds, but will prevent the germination of several annual and perennial weeds – including dandelion – if applied in spring about two weeks prior to their expected germination. A word of caution: if you are in the process of over-seeding an existing lawn, it will prevent those seeds from germinating as well. Other recent options include Fiesta, an iron-chelated product that

Corn gluten meal prevents the germination of several lawn weeds, including dandelions, but will not effect established weeds. Do not apply if you have recently seeded or over-seeded your lawn.

controls dandelions and other broadleaf lawn weeds, and Sarritor, a strain of Sclerotinia minor, a fungal disease specific to dandelions. Studies at the Prairie Turfgrass Research Centre in Olds, Alberta have shown that these three alternatives may be less effective, with reduced weed control, than traditional chemical herbicides. On the positive side, they do not pose any danger to human health or the environment.

Grass Species Visually, grass species are not that different, but it is important to plant a mixture of two or more species and a few cultivars within each of these species, rather than growing a monoculture of one grass species. Follow the adage of not putting all of your eggs in one basket. If drought, cold or pestilence knocks out one grass species or cultivar, you will still

Corn gluten meal is easily applied in a conventional fertilizer spreader.

have a lawn. Conventional lawns – those that are irrigated, fertilized and regularly mowed – are composed of rhizome-forming grasses which knit together to form a sod. On the prairies, lawns are usually a mixture of Kentucky bluegrass and creeping red fescue. More recently, some turf specialists are recommending the replacement of Kentucky bluegrass with chewings fescue. Because of its lower demand for water, fertilizer and pesticides

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89

and its higher tolerance for shade and drought, chewings fescue is often part of a dryland mixture. Most prairie turf grasses are categorized as cool-season grasses. They grow best (and are bright green) in spring and fall when daytime temperatures range from 16 to 24°C (60– 75°F) and soil temperatures are low. Growth is consistent as long as they do not go into moisture stress. During the heat and drought of midsummer, they may respond by decreasing leaf growth and becoming dormant. Although the crown of the plant remains alive, they “go brown.” Watering allows the turf to remain green through the summer. The growth cycle of cool-season grasses peaks in spring (May and early June), Kentucky bluegrass (Poa pratensis) is hardy, deep green, fine textured and long lived. Use a blend of several cultivars.

Best drought-tolerant selections Twenty-five grasses were evaluated over three summers by the Prairie Turfgrass Research Centre in Olds, Alberta. The trials determined how quickly these grasses established from seeding; their ability to

September and October. Root growth remains active until soil temperatures drop below 10°C. Frost rapidly decreases the soil temperatures and growth is restricted until soil temperatures increase the following spring. Non-irrigated lawns – those found on most farmyards and acreages – are composed of bunch grasses such as wheatgrasses and sheep fescue. These generally have a clumpy growth habit and seldom form a true knitted sod. While they thicken and spread over time, they remain individual, tuft-like plants. If seed-

withstand drought; their mature height; and

ed thickly at the time of establishment and mowed regularly, they

their competitiveness with weeds.

fill in more quickly.

Blue grama grass, ‘Elbee’ northern wheat-

Sod-forming grasses recover from damage, wear and tear

grass, ‘Spartan’ hard fescue and ‘Fairway’

more quickly due to their rhizomatous nature. Bunch grasses are

crested wheatgrass exhibited the best of

much slower to recover because they have fewer growing points.

these characteristics, combining low mow-

“Miracle” dryland grasses are sometimes marketed as sub-

ing height, drought tolerance and competi-

stitutes for conventional lawn areas. Many of these are bunch

tiveness with weeds. There was, of course, a

grasses and do not provide a comfortable surface for a human

consistent relationship between the ability of a grass to establish itself quickly from seed and its ability to compete with weeds. On the downside, blue gramas and wheatgrasses were not found to produce a tight

90

producing lush top growth as well as root growth, and again in

body. If your intention is to lie down or walk barefoot on your lawn, you’re better off with the conventional sod-forming grasses.

stand of turf. In contrast, some of the fine-

High-Maintenance, Irrigated Lawns

textured fescues currently being tested as

A conventional prairie lawn is almost always composed of

low-maintenance lawns are proving drought-

Kentucky bluegrass and creeping red fescue. Together these

and shade-tolerant and require less fertilizer.

form an ideal lawn on which to sit, play or walk. They also have

They establish quickly when seeded at the

excellent recuperative potential – if damaged by heavy wear,

recommended rate and generally need to

disease or drought, they recover quickly. But these lawns are

be mowed only once a month, but they are

only maintained by significant inputs of water and fertilizer and

not very tolerant of traffic.

regular mowing.

Creating the Prairie Xeriscape

Kentucky bluegrass (Poa pratensis) Kentucky bluegrass was introduced to North America from

White Dutch clover

Europe during the colonial era. Hardy, deep green, fine textured

Remember the popular song, “I’m look-

and long lived, it is a cool-season grass that spreads by tillers – by sending up new shoots closely adjacent to the original clump – and rhizomes. It forms a dense, hard-wearing sod with roots typically reaching to 15 cm (6 in.) below the surface and occasionally to 25 cm (10 in.). Most cultivars have good spring and

ing over a four-leaf clover”? How long has it been since you went searching for fourleafed clover in your lawn? Prior to World War II, white Dutch clover was an important part of almost all lawn mixtures. With the advent of broadleaf her-

fall colour. Some cultivars become brown during extended hot,

bicides meant to rid lawns of all weeds, clo-

dry periods but green up when watered. Tiller production and

ver lost its place as there was no chemical

root growth are stimulated by shorter days and cooler tempera-

that could eliminate weeds and not affect

tures. They generally stand heavy wear and recover quickly.

the clover. Yet if clover composes 5 percent

Kentucky bluegrass does poorly in shade and under condi-

of a lawn seed mixture, it will supply about

tions of drought or poor fertility. Under high humidity (generally

half the nitrogen needed for a healthy lawn.

not a problem on the prairies), many cultivars are prone to pow-

Many prairie cities have recently reintro-

dery mildew. Kentucky bluegrass requires high inputs of water,

duced clover into their parks’ lawns.

fertilizer and mowing to look good and wear well. A blend of several (of which there are hundreds) cultivars should be used. When selecting a cultivar or mixture, ensure that it is hardy to the zone in which you live rather than one that is mass-marketed through national chain stores. Most cultivars of Kentucky bluegrass appear to have good cold tolerance, but many of the turf seed mixtures marketed through box stores contain perennial ryegrass, which is not cold tolerant. Testing at the Prairie Turfgrass Research Centre showed that -15°C was the lowest temperature these varieties could withstand. The following are older cultivars of Kentuky bluegrass that are recommended for the prairies and are often part of mixtures: ‘Adelphi’ (1972) is dense, low growing and dark green, with good heat tolerance and disease resistance. It looks good despite low maintenance and has excellent low-temperature colour retention and spring green-up. It establishes quickly. ‘Banff’ is a dwarf cultivar with good all-season colour. It is resistant to both powdery mildew and snow mold. It is very winter hardy. ‘Baron’ (1970) is a dark green, dwarf cultivar with high density. It establishes quickly and has good disease resistance, except for susceptibility to snow mold. ‘Birka’ (1968) is a medium- to fine-textured, medium-dark

White Dutch clover, once a valued part of our lawns, is making a well deserved comeback. If it composes 5 percent of a lawn seed mixture, it will supply about 50 percent of the lawn’s required nitrogen.

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green, dwarf cultivar. It is shade tolerant, resistant to powdery mildew and responds well under low-maintenance conditions. ‘Nugget’ (1965) is dense and low growing. It was developed in Alaska and is resistant to powdery mildew and snow mold. It is somewhat shade tolerant but has poor low-temperature colour retention and spring green-up and poor heat tolerance. It is very wear tolerant. ‘Park’ (1975) is a blend of fifteen selected strains from Minnesota. It germinates quickly, with good seedling vigour and has a rapid establishment rate. Its fertility requirements are low, but it is susceptible to snow mold. New varieties are being developed and released all of the time and local institutional testing may be two to three years after their introduction. The following are among the more recently introduced cultivars available for the prairies: ‘Alene’ is very hardy, with early spring green-up and drought tolerance. ‘Alpine,’ a dark green, dense cultivar with quick spring greenup, is both heat- and cold-tolerant and resistant to powdery mildew. ‘Golden Nugget’ (a cross of ‘Limousine’ and ‘Nugget’) is dense, dwarf, medium-dark green, has excellent wear tolerance and is disease resistant. ‘Limousine’ scored very high in the 2004 turf-grass trials conducted by Olds College. It is dense, wear and shade tolerant, Creeping red fescue, seen here unmowed, is the other major component of irrigated lawns. It is low growing, fine textured, medium to dark green, and tolerates shade, low fertility and drought.

disease resistant and germinates quickly. ‘Marquis’ is drought resistant with good sod-forming ability. ‘Midnight’ is very dark blue green, dense, drought tolerant, disease resistant and will grow in full sun to light shade. ‘Orfeo’ has quick germination and establishment, is shade tolerant and is moderately salt tolerant. ‘Quantum Leap’ (a cross of ‘Limousine’ and ‘Midnight’) is dark green, shade- and heat-tolerant and resistant to disease and chinch bugs. ‘Rugby II’ is dark green, shade tolerant and disease resistant. ‘Touchdown’ has excellent spring green-up, is very wear tolerant and is resistant to powdery mildew. SEEDING RATE: 0.5–0.7 kg/100 m2 (1–1.5 lb/1,000 ft2)

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Creating the Prairie Xeriscape

Creeping red fescue (Festuca rubra var. rubra) Creeping red fescue, also native to Europe, is a low-growing, fine-textured, medium to dark green grass with narrow, stiff blades. It can be mowed to 7.5 cm (3 in.). It spreads by tillering and rhizomes. Its root system is dense and fibrous. It has moderate “wear resistance” and stands up well to foot traffic and use, but has poor recuperative ability due to weak rhizomes. It is tolerant of shade, low fertility and drought. It does not tolerate wet soils or excessive nitrogen and discolours in hot or dry weather. Seed germinates within two weeks. Creeping red fescue blends well with Kentucky bluegrass, but requires only 20 percent of the nitrogen needed by Kentucky bluegrass. It is believed to have a weak allelopathic effect, inhibiting the germination and/or growth of some other plants (but apparently not chickweed!). Recommended cultivars of creeping red fescue include: ‘Boreal’ (Alberta, 1966) is a very hardy, fine-textured, medium blue green grass that is quick to establish and has a deep root system. ‘Dawson’ (British Columbia) is a fine textured, medium blue green. ‘Jasper’ (Alberta) is dark blue green and coarser than many of the fescues. SEEDING RATE: 1.6–2.0 kg/100 m2 (3.5–4.5 lb/1,000 ft2)

Low-Maintenance, Non-irrigated Lawns

Non-irrigated lawns require occasional mowing but never water or fertilizer.

Low-maintenance grasses are those species and cultivars that persist with few inputs, requiring little water, fertilizer or mowing. Instead of being smooth and soft, they tend to be clumpy, lumpy and rather harsh on the human hide. One does not walk barefoot on them. They are usually mowed at 7.5 to 15 cm (3–6 in.) – somewhat higher than conventional lawn grasses – and removal of 40 percent of the leaf blade is considered acceptable. These grasses are best viewed from a distance but fit in nicely with the xeriscape concept. Once established, they require only occasional mowing and almost no irrigation or fertilizer.

Fescues (Festuca spp.) Although fescues are considered bunch grasses, many of the newer cultivars have been selected because they lack this

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93

characteristic. They are slow to establish, but once established may have extensive root systems. Fescues have low water and fertility needs and are adapted to many soil types. Chewings fescue (Festuca rubra var. commutata) is native to Europe and has narrow, dark blue green leaves. It can be mixed with creeping red fescue and Kentucky bluegrass in conventional lawns. It reproduces by tillering. It is shadeand drought-tolerant and is adapted to infertile, acid soils. It is believed to be weakly allelopathic, exuding a compound from its roots that inhibits the germination and/or growth of other plants. Chewings fescue and creeping red fescue make a good blend, similar in height to a conventional lawn but requiring less water, fertilizer and mowing. Recommended chewings fescue cultivars include: ‘Agram’ is fine textured, medium blue-green and very disease resistant. ‘Arctared’ is fine textured, dark green, with a rapid establishment rate. Generally composed of fescues, Canada bluegrass, wheatgrasses or Russian wildrye, non-irrigated lawns are visually attractive but are not a soft resilient surface.

‘Banner’ and ‘Victory’ are fine-textured, dark blue-green, dwarf cultivars with good disease resistance. ‘Longfellow II’ is a fine-textured, dark green, shadetolerant cultivar with excellent disease- and insectresistance. ‘Silhouette’ forms a dense turf that performs well in sun or shade and has excellent drought tolerance. Sheep fescue (F. ovina) is strongly clumping and blue green in colour. It has good drought tolerance and is widely adaptive, from dry to moist soils and from basic to acidic. It is indigenous to both Europe and North America. ‘Nakiska’ is a relatively new cultivar with a less clumpy habit. It is especially recommended for reclamation and for sandy or gravelly soils. It is shade tolerant and survives under taller-growing species. ‘Azay’ has been used successfully on toboggan hills. Hard fescue (F. ovina var. duriuscula), native to Europe, has a mature height of 15 to 25 cm (6–10 in.), with wider blades and a more greyish-green colour than other fescues. It is slow growing and slow to establish, but once established forms a low ground cover that is competitive with weeds. Growth slows down but does not stop during the heat of the summer.

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It is both drought- and shade-tolerant. Newer cultivars seem less clumpy and many contain endophtyes – naturally builtin biological controls against insects such as sod webworms and chinch bugs. Recommended hard fescue cultivars include: ‘Aurora’ is dark blue green and fine textured with a 7.5 to 15 cm (3–6 in.) mowing height and good drought tolerance. ‘Biljart’ (Netherlands, 1963) is dense, deep green, very fine textured, tufted and drought resistant. It is considered one of the best turf-type hard fescue cultivars. ‘Durar’ (1949) is more clumpy but both drought resistant and shade tolerant. ‘Eureko II’ is a dark green, dense bunch grass that spreads slowly through tillering. Once established, it tolerates drought, low fertility and shade on well-drained sites. It is endophyte enhanced for disease and insect protection. ‘Reliant’ is another good low-maintenance cultivar. ‘Spartan’ is dark blue with a 7.5 to 15 cm (3–6 in.) mowing height and it blends in well with bluegrasses. Once established, it is aggressive and competitive with weeds. ‘Spartan II’ has improved heat tolerance and is endophyte enhanced, shade tolerant, disease resistant and adapted to low fertility. It is low growing. SEEDING RATE: 1.6–2.0 kg/100 m (3.5–4.5 lb/1,000 ft ) 2

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Canada bluegrass (Poa compressa) Shorter growing (10–30 cm/4–12 in.) and coarser than Kentucky

Sheep fescue and hard fescue are both widely used for non-irrigated lawns. They are drought-tolerant and although they may require occasional mowing, they do not need to be fertilized or irrigated.

bluegrass, Canada bluegrass is blue green in colour and adapted to soils from moist to dry and infertile and from acid to basic. Native to western Eurasia, it may be native or introduced to North America. Although it has a fibrous root system with extensive rhizomes, its growth habit is clumpy. It is tolerant of wear, stress and drought and is disease resistant. ‘Reubens’ is less clumpy to non-clumpy, with a 10 cm (4 in.) mowing height. It requires far fewer inputs than Kentucky bluegrass and has early spring green-up. It tolerates acid soils. SEEDING RATE: 0.5–1 kg/100 m2 (1–2 lb/1,000 ft2)

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Wheatgrasses (Agropyron spp.) Although very drought tolerant, wheatgrasses show a strong clumping habit and are less dense than other grasses. Crested wheatgrass (Agropyron cristatum, syn. A. pectiniforme) is native to Siberia but has become naturalized in some areas of North America. It is a clumping bunch grass with excellent drought tolerance. Some cultivars are lower growing than the standard 20 to 40 cm (8–16 in.). The species seeds readily and if allowed to set seed will become invasive once established, particularly if planted near or among native grass species. ‘Fairway’ crested wheatgrass remains one of the best grasses for non-irrigated lawns. Its leaves are green and somewhat wider than those of Kentucky bluegrass. Native to the cold, dry regions of Siberia, it is shorter, denser and finer stemmed than the species, as well as slower growing. It is an upright bunch grass with an extensive and deep fibrous root system. It has a good germination and establishment rate and propagates naturally by seed. Drought tolerant, cold hardy and tolerant of mowing, it is adapted to a wide range of soils. It becomes brown during Crested wheatgrass is a clumping bunch grass with excellent drought tolerance. ‘Fairway’ is one of the best cultivars.

hot, dry periods. Very competitive with weeds and useful in erosion control, it is invasive and should not be mixed with native grass species. Northern wheatgrass (A. dasystachyum), a native species, is relatively low growing at 20 to 30 cm (8–12 in.). With a strong spreading habit and extensive rhizomes, it establishes

Say No to Bromegrass Smooth bromegrass (Bromus inermis) is no

quickly and is well adapted to slopes, banks and sandy soils. Greyish green in colour, it has a clumpy appearance.

longer recommended for non-irrigated

The cultivar ‘Elbee’ has excellent drought tolerance and

areas (or irrigated lawns) because of its ag-

is widely used for reclamation.

gressive nature. Bromegrass is an open, coarse-textured, cool-season grass that is drought tolerant and requires little fertility. Native to Europe, Siberia and China, it spreads by rhizomes and seed and has an extensive root system. It is intolerant of close mowing, not resilient to wear and becomes brown during extended drought. Extremely invasive, it naturalizes quickly and is very competitive with native grass species.

Streambank wheatgrass (A. riparium) is a dryland species used in pure stands or in mixtures with small amounts of Kentucky bluegrass. Native to North America, including western Canada, it is a low-growing, sod-forming grass, with narrow leaves and stems 30 to 80 cm (12–30 in.) high. It has vigorous rhizomes, is long-lived and colonizes both by seed and its spreading root system. It flourishes on well-drained soils, withstands mowing and is highly competitive with weeds under dryland conditions. Long recommended for farm lawns, it establishes quickly with good germination and seedling vigour. SEEDING RATE: 1.4–2.3 kg/100 m2 (3–5 lb/1,000 ft2)

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Russian wild ryegrass (Elymus junceus) This dryland grass species is used in pure stands or in mixtures with small amounts of Kentucky bluegrass. Native to western Siberia, it is used primarily as a pasture grass, a reclamation species and for sand dune stabilization. It is a tall (1 m/3–4 ft), densely tufted bunch grass with a deep root system. It is easily propagated by seed, reseeding itself naturally if left unmowed. It is adapted to both light and heavy soils, as well as alkaline and saline soils. It is intolerant of shade, but is tolerant of traffic and is not as invasive of adjacent areas as crested wheatgrass. It is considered one of the best grasses for nonirrigated farmyards and lawns. Many of the improved cultivars lack seedling vigour and may take two to three years to become established. An exception is ‘Cabree,’ which has outstanding seedling vigour. Other cultivars include ‘Mayak,’ ‘Sawki,’ ‘Swift,’ ‘Tom’ and ‘Piper.’ SEEDING RATE: 2.3 kg/100 m2 (5 lb/1,000 ft2)

Russian wild ryegrass is used primarily for pastures, reclamation and sand dune stabilization. It is adapted to a variety of soils and is one of the best grasses for non-irrigated lawns.

Native grasses Native grasses come in many colours and textures and together form a mosaic rather than a uniform swath. They change through the seasons as conditions of temperature and precipitation change. Once established, native grasses will perform well if allowed to grow to maturity. Most do not tolerate the intensive use we give our conventional lawns. These grasses have generally been used in low-maintenance situations where their primary function is visual. Native grasses should be kept separate from traditional lawn and pasture grasses, with which they will seldom successfully compete, especially during the establishment stages. Bromegrass and crested wheatgrasses are particularly aggressive and will choke out native grasses, which are much slower to establish. Mixing aggressive pasture grasses and non-aggressive native species is seldom successful. Although much more readily available than it was a few decades ago, native grass seed may still be relatively expensive. Use local seed sources, as plants will be better adapted to the region in which they are growing than the same species from a more distant location. Blue grama (Bouteloua gracilis) was one of the top grasses in low-maintenance trials conducted by the Prairie Turfgrass

Needle and thread grass (Stipa comata), one of our native grasses, is well used in low maintenance situations where its primary function is visual. It will not tolerate the intensive use we give our conventional lawns.

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Research Centre in Olds, Alberta. Although it is a densely tufted bunch grass of up to 20 cm (8 in.) in height, blue grama will form a sod cover in about a year if mowed monthly through the summer. The narrow, grey green leaves are curly. It has excellent heat- and drought-tolerance, but poor shade tolerance. It is well adapted to both clay and sandy soils and is an important pasture species. Other native grasses being used in restoration projects or for non-irrigated spaces include: • needle and thread grass (Stipa comata) • tufted hair grass (Deschampsia caespitosa) • big bluestem (Andropogon gerardii) • little bluestem (Schizachyrium scoparium) • western wheatgrass (Agropyron smithii) • northern wheatgrass (Agropyron dasystachyum) Western wheatgrass is valuable as a salt-tolerant species in saline soils.

Tufted hair grass (Deschampsia caespitosa) is another native grass that is lovely to look at but will not tolerant the wear we give our conventional lawns. Nor will it compete with pasture grasses.

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“We plant flowers and vegetables for ourselves, but trees we plant for future generations.”

PART 2

Xeriscape Plants Many dought-tolerant plants have been part of prairie gardens for years, but until now we may have thought of them only as attractive plants.

About Part 2 The plants featured in the following chapters are all drought tolerant. Those that are extremely so are designated by the icon/symbol

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The rest are

moderately drought tolerant or are “drought tolerant once established” and have developed mature root systems. Note that although the common name is listed first, all plants in this section are listed alphabetically by genus and species name.

PREVIOUS PAGE: ‘Autumn Magic’, an aronia or chokeberry (Aronia melanocarpa) selection from the University of British Columbia Botanic Garden, is noted for its glossy leaves and brilliant reddish-purple fall foliage. It is up to 1.5m/5 ft in height.

CHAPTER 7

Trees & Shrubs We plant flowers and vegetables for ourselves, but trees we plant for future generations. By the time a tree reaches its mature height, we will probably be long gone from that particular garden. Settlers who came to the almost treeless prairies were quick to plant trees and shrubs and without that investment in the future, the prairies would be a very different and much more difficult place in which to live and garden. Ranging from extremely low ground covers to towering evergreens, the woody ornamentals with the greatest drought tolerance have made the greatest difference. Some of the first trees and shrubs planted by settlers were native to the prairies, found in river valleys, coulees, in our northern forests or areas like the Cypress Hills. Others were very deliberately introduced from similar climates of Asia. Many others are the result of an early generation of prairie plant breeders seeking to develop trees and shrubs with beauty and disease resistance that would be hardy here. Among these horticultural pioneers were Frank Skinner, Bert Porter, W. J. Boughen, Les Kerr, Percy Wright, George Bugnet and John Wallace, along with the early Agriculture Canada Research Stations at Indian Head, Saskatchewan, Beaverlodge, Alberta and Morden, Manitoba. More recently, individuals such as Rick Durand, Bob Bors, Wilbur Ronald, Lynn Collicut and Dale Herman have made introductions that have added beauty to the prairie landscape.

Subalpine fir (Abies lasiocarpa)

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If any conifer should have much wider availability and use, it’s

Trees and shrubs provide the backbone of this drought tolerant mixed borders: a dwarf blue spruce, Swiss stone pine, and tightly pruned cotoneaster. Giving variety to the pathway are veronica in the slate wall and fernleaf peonies above it.

subalpine fir. A handsome evergreen with dense, bright green, flat needles that are exceptionally soft and huggable, subalpine fir has a narrow stately form and a spread of only 2 to 3 m (6.5–10 ft). It stands like an exclamation point on your landscape!

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The common name refers to its native habitat, the subalpine forest zone of the Rocky Mountains, from Alberta and British Columbia and as far afield as Alaska to New Mexico, at elevations up to 2,300 m (7,500 ft). To ensure hardiness, it’s crucial that the seed source of the trees you purchase be from its coldest range. Trees from Alberta are hardy to zone 2 of the prairies. Abies is from the Latin word abire, to rise, a reference to its height (15 m/50 ft), while lasiocarpa is from the Greek lasios, meaning shaggy and carpos, fruit, describing the attractive, dark purple, oblong cones of about 7.5 cm (3 in.). The bark is smooth and ash grey. CARE: Plant in full sun on well-drained soil. It is extremely

drought tolerant once established and is insect- and disease-free. USE: Its relatively slender girth makes it suitable for both large and small areas, as a specimen tree, for screening or hiding utility poles.

Maple (Acer spp.) Subalpine fir (Abies lasiocarpa) has soft needles and a small base, and is like an exclamation point in your landscape.

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Of the many maples familiar to prairie gardeners, only the ginnala maple and the Manitoba maple are both hardy and drought tolerant. The genus name is from the Latin word for sharp and describes the hard wood, used by the Romans for making spear handles. Although their foliage is quite different, both trees have two-winged samara that distribute seed through the wind. Amur or ginnala maple (Acer ginnala) is an absolute standout for fall colour, varying from yellow to orange to red, becoming bright scarlet at its best. It is native to China, Japan, Siberia and Manchuria, including the Amur River valley, from which it takes one of its common names. The species name, from the Greek ginnos, a small mule, refers to the plant’s size and toughness. Fast growing, it is considered either a large shrub or, if pruned to a single trunk, a small, rounded tree of about 4.5 m (15 ft). The leaves are three-lobed, with the middle lobe longer than the side lobes. The leaf veins and petioles are red, as are the paired, winged seed pods or samaras, later ripening

The Amur or ginnala maple (Acer ginnala) is a small tough tree with outstanding orange-red fall foliage.

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to a straw colour. These are much showier than the inconspicuous greenish-white flowers, produced in May.

Among the selections: ‘Atomic’ (‘Durglobe’) is a multi-stemmed shrub with brilliant fall colour. It has a rounded form with a height and spread of only 3 m (10 ft). Selected by Rick Durand, a Manitoba plant breeder, it is suitable for hedging. ‘Bailey’s Compact’ is 4 m (13 ft) in height and turns yellow to orange-scarlet in fall. ‘Durone’ (‘Ventura’) is a hybrid of Tartarian and Amur maple developed by Rick Durand. It is hardy to zone 2 and resistant to lime-induced iron chlorosis. It reaches 6 m (20 ft) in height, with a spread of 4.5 m (15 ft). ‘Flame’ has a rounded form and is slightly smaller than the species (4 m/13 ft height and spread). It has a single trunk and as its name suggests, intense orange red fall colour. ‘Royal Crown’ (‘JeFUM’) is a University of Minnesota introduction with a clump form, 6 m (20 ft) in height with a spread of 4.5 m (15 ft) and resistance to lime-induced iron chlorosis. CARE: Amur maple prefers well-drained soil with a pH below

7.0 and full sunlight for best fall colour, although it tolerates partial shade. Susceptible to lime-induced iron chlorosis in alkaline soils, some of the newer introductions have been selected for resistance to this problem.

‘Durone’ (‘Ventura’) maple is a hybrid of Tartarian and Amur maple developed by Rick Durand and hardy to zone 2.

USE: It is an excellent choice for smaller urban yards or massed in larger spaces, as an informal untrimmed hedge or for screening. It’s a tough little tree for dry, windy, inhospitable situations. The seeds, retained through winter, are a treat for grosbeaks and other birds. Manitoba Maple, box elder (A. negundo). Familiarity sometimes breeds contempt, but without Manitoba maple or box elder, life would have been considerably more difficult for early prairie settlers, for whom it provided shelter and shade. It still has a place in larger landscapes. As the common name implies, Manitoba maple is native to the prairies and has been used extensively as a shelterbelt, shade and boulevard tree. The whitish wood is similar to that of the boxwood, hence the other common name, box elder. It is fast growing, reaching a height of 15 m (50 ft) or more during its sixty-year lifespan. The leaves resemble those of ash: compound with three to seven irregular lobes. Male and female flowers are on separate trees. The female flower is greenish yellow, in drooping clusters. The male

‘Baron’ is a seedless male selection of Manitoba maple (Acer negundo).

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flower is a dense red tassel. Both appear before the leaves. Only the female trees produce seeds, in winged, V-shaped seed pods that persist into winter. If you don’t want seedlings, purchase a male tree. ‘Baron,’ introduced from the Agriculture Canada Research Station at Morden, Manitoba, is a male (seedless) selection of about 15 m (50 ft) with an upright, oval to round growth habit and bright yellow fall foliage. CARE: Manitoba maples are adapted to full sun and a wide

range of soils. They do not do as well in shade. Problems include sensitivity to 2,4-D (especially in shelterbelts when adjacent fields are sprayed) and their attractiveness to aphids, which excrete sticky “honeydew” onto decks, picnic tables and vehicles parked below the tree canopy. They are also occasionally attacked by cankerworms and red and black box elder bugs. USE: In spite of their faults, they are invaluable for large land-

Female Manitoba maple trees (A. negundo) have flowers in long drooping racemes and will produce seeds. Male trees will not.

scapes and dry, windy sites. Although unsuited to smaller urban lots, they are excellent for shelterbelts, farmsteads or acreages and kids will find them second to none for tree houses and climbing. As well, they provide food and cover for a wide variety of birds and may be tapped for maple syrup.

Saskatoon berry (Amelanchier alnifolia)

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Long used by Indigenous peoples and early European settlers, saskatoons have now become a major commercial fruit crop on the prairies. The species name, alnifolia, means alder-like leaves, referring to its similarity to another native prairie shrub. Well known for its sweet edible fruit, the saskatoon also has ornamental flowers and attractive gold fall foliage colour. The dense, erect clusters of fragrant white flowers appear in May, followed by dark blue berries in midsummer. It shows tremendous variation in form in the wild, with heights generally ranging from 2.7 to 4.5 m (9–15 ft) and spreads of 1 to 2 m (3–7 ft). Consider a cultivar’s ultimate height and spread as well as its tendency to sucker when making your selection. Some are better suited to larger lots and some to smaller urban yards. Among the selections are: ‘Honeywood’ (2–3 m/7–10 ft), introduced by Bert Porter of

Saskatoon berries (Amelanchier alnifolia) are extremely drought tolerant with the bonus of lovely flowers in early spring and delicious fruit in mid-summer.

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Honeywood Nursery, has large clusters of large fruit and begins fruiting at an early age. ‘Martin’ (2.7 m/9 ft), a seedling of ‘Thiessen,’ was selected by Dieter Martin of Langham, Saskatchewan for its large fruit, exceptional flavour and uniform ripening.

‘Northline’ (1.5 m/5 ft) was one of the early introductions from John Wallace of Beaverlodge Nursery in Alberta. Selected in the 1960s, it is very productive but suckers freely. ‘Smoky’ (3.7 m/12 ft), introduced in 1952, was part of a hedge on the Beaverlodge Experimental Farm. It has medium-size sweet fruit and suckers freely. ‘Thiessen’ (4.5 m/15 ft) was introduced by George Krahn of Lakeshore Nurseries. It blooms early and produces large fruit. CARE: Saskatoons grow on a wide range of soils, in sun or par-

tial shade. They are less fruitful in shade. They are extremely drought tolerant once established. If grown within a few kilometres of junipers, they may become infected with saskatoon-juniper rust, especially following warm, rainy springs. Orange lesions on the leaves and fruit of the saskatoon plants characterize this fungal disease. USE: Saskatoons are excellent as part of an informal shrub

border, as a small specimen tree or tree grouping. They are widely used in shelterbelts, naturalization and transition zones in large rural landscapes, where they provide cover and food for birds. The flowers and edible berries are a bonus.

Leadplant and false indigo (Amorpha spp.)

Long used by Indigenous peoples and early settlers, saskatoon berries are now an important commercial fruit crop on the prairies.

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Sometimes botanical names can be misleading. The Greek word for this genus, amorphos, means shapeless or deformed and describes the single-petalled flowers, conveying a rather dismal description. In reality, the spikes of small blue-purple flowers with their bright orange stamens that appear in June and July are very attractive, especially against the fine-textured silver foliage. Both species mentioned here tend to be rather sprawling, limiting their use to informal landscape situations. Native to areas of the prairies as well as the American Midwest, both false indigo and the leadplant have pinnately compound leaves. Leadplant (Amorpha canescens) is up to 1 m (3 ft) in height. The species name, canescens, means ashy-grey, a reference to the leaves. The common name arose from the mistaken belief that the presence of this shrub indicated lead deposits in the soil. False indigo (A. fruticosa) is closely related to leadplant (both are members of the pea family and are able to fix nitrogen) but taller. The common name alludes to its use as a blue dye. A shrub of 1 to 1.2 m (3–4 ft), it is mound-like when young but may become leggy and somewhat sprawling with age.

False indigo (Amorpha fruticosa) has fine foliage, lovely blue flowers, and can fix nitrogen.

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CARE: Both grow well in poor, dry soils in full sun and are saline

tolerant. In partial shade, they flower less and sprawl more. USE: Because of its suckering habit, leadplant is useful for

naturalization, stabilizing soil and roadside plantings. Due to its form, false indigo is not often seen in well-manicured landscapes either, but it is useful in a rural naturalized setting. It is a nectar plant for butterflies. Both can be found at nurseries specializing in native plants.

Bearberry, kinnikinnick (Arctostaphylos uva-ursi)

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In Russia, the leaves were once used for both tanning leather and tea. The Greek word arctos means bear, while staphyle means a bunch of grapes. Uva-ursi repeats the concept, meaning bear’s grapes. Both the common and botanical names refer to bears’ fondness for the fruit. Bearberry (Arctostaphylos uva-ursi) is an attractive, low, evergreen ground cover.

An evergreen woody ground cover, bearberry is circumpolar in the northern hemisphere and native to the prairies. It forms a prostrate mat about 15 cm (6 in.) in height. Its thick, glossy green leaves generally turn bronzy green in winter. The pinkand-white flowers are urn-shaped. The fruit is bright scarlet, 1 cm (less than 0.5 in.) in diameter and persists through winter. ‘Vancouver Jade,’ a University of British Columbia introduction, is readily available, though less hardy than the species. Plant in a protected location. CARE: Bearberry grows in full sun to full shade on a range of

well-drained, acid or alkaline soils and is saline tolerant as well. It is difficult to transplant successfully from the wild, so it is best to purchase containerized plants. USE: This excellent ground cover fits in well in a perennial bor-

der or rock garden. Birds (and bears) enjoy the berries.

Chokeberry, aronia (Aronia melanocarpa) Native to a wide sweep of eastern North America from Minnesota to Tennessee, chokeberry or aronia has only been commercially available on the prairies for the last decade but has proved itself hardy and drought tolerant, with multi-season landscape value. The fruit resembles mountain ash, hence the genus name Aronia, which is from the Greek aria, referring to a species of mountain Eventually forming colonies through suckering, chokeberry (Aronia melanocarpa) has white flowers in spring.

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ash, while melanocarpa (black fruit) describes the berries. The common name alludes to the astringency of the raw fruit. About 1 to 1.2 m (3–4 ft) in height, aronia eventually forms large colonies through suckering. The oval, dark green, serrated

leaves are simple and alternate and turn a brilliant red in the fall. Dense, flat clusters of fragrant, white flowers are produced in late spring, developing into small (1 cm/0.5 in. diameter), purplish-black berries by late summer. ‘Autumn Magic’ (up to 1.5 m/5 ft) was selected from the University of British Columbia Botanic Garden for its glossy leaves, overall form, larger fruit and brilliant reddish-purple autumn foliage. CARE: Adapted to a range of soils, aronia grows in full sun to

partial shade and is drought tolerant once established. It is pest- and disease-free. USE: Excellent as a mass planting or for naturalization, it is best placed in a larger landscape where it has room to expand. The fruit can be processed into jams and jellies.

Sagebrush (Artemisia spp.)

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Members of this genus have been noted for their medicinal qualities since classical times. The genus name honours Artemis, the Greek goddess of chastity. In our landscapes, they are valued for their silver foliage and ability to thrive in difficult situations.

Aronia produces dark blue berries suitable for jams and jellies in late summer and the foliage turns a brilliant red in the fall.

Both are native to the prairies. Aromatic hoary sagebrush (Artemisia cana) is a low, muchbranched shrub, generally about 0.6 m (2 ft) in height. With a twisted, gnarled appearance and shredding bark, it has character and in many ways epitomizes the tough Canadian prairies. The species name, cana, is from the Latin meaning grey white and describes the silver foliage. The small hairy leaves are alternate, sessile, narrow and pointed. Young twigs are grey and have tiny hairs. Small yellow flowers in narrow leafy clusters appear in July and August. It suckers moderately. Big sagebrush (A. tridentata) has two qualities that make its grey white foliage of interest to gardeners: its pungent, sagelike fragrance and the felt-like texture. A rather rare prairie shrub, big sagebrush has a single short trunk and grows to about 1.2 m (4 ft) in height. Tridentata describes the three teeth found at the tip of each leaf. The bark becomes shredded with age. The silver leaves are wedge-shaped. CARE: Grow in full sun in well-drained soil. Big sagebrush may

be pruned in spring to stimulate new growth. USE: Both are useful for naturalization, mass plantings and transition areas in large rural landscapes on dry, difficult sites.

Aromatic hoary sagebrush (Artemisia cana) shown here and the big sagebrush (A. tridentata) are useful for naturalization and mass plantings on dry, difficult sites.

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They provide a sharp contrast when planted next to shrubs with red purple foliage, such as barberries, ninebarks or purple chokecherries. They are generally available only at nurseries specializing in native plant material.

Japanese barberry (Berberis thunbergii) It’s hard to believe that we once landscaped without barberries. The genus as a whole was long banned in the prairies because some of the species were alternate carriers of stem rust of wheat. Japanese barberry is not a carrier and restrictions were lifted on its use and importation into the prairie provinces by Agriculture Canada in 2001. The genus name is derived from the Arabic word for its fruit, berberys, while the species name honours Carl P. Thunberg (1743–1828), a plant collector in Japan and colleague Introduced about a decade ago, ‘Emerald Carousel’ barberry (Berberis thunbergii x B. koreana) has brilliant red fruit and foliage in the fall.

of Linnaeus, the father of modern-day plant nomenclature. It’s called “barb” berry for a reason: the sharp, needle-like spines along the stems mean that it’s lovely to look at but decidedly not huggable. Native to Japan, these shrubs are dense, rounded and multi-stemmed. Most of the cultivars range in height from 0.6 to 1.8 m (2–6 ft) and are grown primarily for their colourful foliage, generally yellow or pink purple. The leaves are deciduous in the prairie climate. The small yellow flowers are inconspicuous and usually hidden by the foliage. The bright red berries sometimes persist through the winter. The species is rarely available, but there are many cultivars: ‘Burgundy Carousel,’ only 0.6 m (2 ft) in height with a 1 m (3 ft) spread, has purple summer foliage, becoming deep purple in fall. ‘Cherry Bomb’ is 1.2 m (4 ft) height and spread and deep crimson all season with an open, branching form. ‘Concorde’, a dwarf at only 0.6 m (2 ft) in height, with a spread of 1 m (3 ft), is slow growing and deep red purple. ‘Emerald Carousel,’ with a height and spread of 1 m (3 ft), is a hybrid of B. thunbergii and B. Koreana. It has deep green foliage, orange in spring and turning reddish in fall. ‘Golden Nugget’ is compact and mounded, 30 to 60 cm (12– 24 in) in height and spread. New spring growth is golden with

‘Golden Nugget’ barberry (B. thunbergii) is compact and mounded with lovely golden-orange foliage in spring.

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orange tones, becoming golden during summer and orange pink in fall. ‘Jade Carousel,’ 1 m (3 ft) in height with a spread of 1.2 m (4 ft), has green foliage turning red in fall.

‘Rose Glow,’ 1 m (3 ft) in height and spread, is a 1957 Dutch introduction, with mottled rose pink foliage in spring, becoming deep purple by fall. ‘Royal Burgundy’ is very dwarf, 0.6 m (2 ft) in height and spread, with burgundy foliage in summer, turning deeper burgundy in fall. ‘Royal Cloak’ is one of the larger cultivars (1.2 to 2.4m/ 4–8 ft) in height and spread), upright and arching with dark reddish-purple foliage. ‘Ruby Carousel,’ 1 m (3 ft) in height and spread, has reddishpurple foliage in summer and fall. ‘Sunsation’ is vase-shaped and more upright, reaching 1.2 m (4 ft) in height and spread. It is yellow in summer with golden hues in fall. CARE: Place in full sun or light shade in well-drained soil.

Drought tolerant once established, they may die back if exposed to very cold temperatures in late fall or early winter without an insulating snow cover. The purple types seem more susceptible, but often recover by midsummer. USE: Plant barberries in a mixed or shrub border, rock garden, as an informal untrimmed hedge or as a mass planting.

Caragana, pea shrub (Caragana spp.)

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As much of a prairie icon as our rapidly disappearing grain

One of the most popular barberries, ‘Rose Glow’ has mottled pink foliage in spring and is about 1 m (3 ft) in height and spread.

elevators, the once ubiquitous hedge of common caragana can hardly be considered ornamental, but many of its cultivars are both useful and attractive. First introduced to western Canada from Siberia in the 1880s, caragana is native to Russia, Siberia, Mongolia and China. It is well adapted to prairie conditions and is still used extensively for hedging and farm shelterbelts. It is among the most shade tolerant of our shrubs. Caragana arborescens, the common caragana of shelterbelts, is about 4.5 m (15 ft) in height, upright and spreading. It becomes leggy with age if not rejuvenated by pruning it to ground level every ten to fifteen years. The pinnately compound leaves give the plant a fine-textured appearance. A member of the legume family, it has yellow, pea-like flowers that are borne profusely in June, followed by long pods, which split open audibly during the hot days of August. Seeds germinate readily in nearby cultivated garden areas and naturalize in adjacent bush or woods.

Anyone who grew up on the prairies is familiar with pea shrub or caragana (Caragana spp.) and its yellow, pea-like flowers borne so profusely in June.

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Among its more valuable landscape cultivars are: Fern-leafed caragana (C. arborescens ’Lorbergii’) is a genetic mutation or “sport.” It is about 1.8 m (6 ft) in height, with extremely fine-textured leaves resembling those of the asparagus fern. It is generally grafted onto a “standard” stem of ‘Sutherland’ caragana. It may be oddly attractive as a specimen plant or in a mixed border in a smaller landscape. Weeping caragana (C. arborescens ‘Pendula’) has normal caragana foliage but a weeping habit. It is also generally grafted onto a standard. On its own roots, it is useful as a ground cover, particularly on a bank or slope. Its twisted stems are attractive in winter. ‘Sutherland’ caragana (C. arborescens ‘Sutherland’) has a narrow, upright columnar form of 2.7 to 3.7 m (9–12 ft). It can be used where a vertical accent is needed, for screening or hiding utility poles. It does not tend to sucker. ‘Walker’ caragana (C. arborescens ’Walker’) is both weeping and fine-leaved and therefore of great value. Although generally available grafted onto a standard, it is useful on its own roots as a ground cover or cascading over a ‘Walker’ caragana (C. arborescens ‘Walker’) is usually grafted onto a standard and has a weeping form.

retaining wall. Globe caragana (C. frutex ‘Globosa’) is compact (1 m/3 ft in height and spread) and carries its foliage right to the base. It does not flower. In a more formal landscape, it can be used as a low hedge. It’s also excellent for hiding smaller outdoor electrical or air conditioning units. Pygmy caragana (C. pygmaea) is fine-textured, moundshaped, non-suckering and about 1 m (3 ft) in height and spread. Because it is spiny, it’s valuable as a barrier planting or impenetrable low hedge. CARE: Extremely drought tolerant, caraganas are also salt tolerant. They do best in full sun but will also grow in shade (as anyone living with an old shelterbelt will testify). Plant in well-drained soil; caraganas do not tolerate flooding. Suckers arising from the rootstock onto which cultivars have been grafted should be removed. Caraganas are sometimes attacked by blister beetles.

Globe caragana (C. frutex) has a perfect globe form and is ideal for low hedging in a more formal landscape.

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USE: Depending on the selection, caraganas may be used as specimen plants, high or low hedges, screening, ground covers or in shelterbelts. They are excellent for “traffic control” (such as barrier plantings to discourage children from chasing a ball into a farm septic field) and provide cover for wildlife.

Because of their size and tendency to sucker and self-seed, only a few are suitable for smaller yards.

‘Delta’ hackberry (Celtis occidentalis) For a “lakeside” tree, the ‘Delta’ hackberry has proven itself surprisingly drought tolerant. Native to eastern North America, this selection of hackberry is from a stand on the southern shore of Lake Manitoba north of Portage la Prairie. For years I assumed that ‘Delta’ referred to its location, presumably where a river entered the lake. In fact, the name results from a tradition of naming railway stations with the letters of the Greek alphabet. This area is now called Delta Beach. Upright, reaching to about 15 m (50 ft) in height, oval to rounded in form and slow growing, hackberry resembles the American elm, to which it is related. The hackberry, however, does not get Dutch elm disease. The oval, green leaves are pointed, asymmetrical at their base and turn pale yellow in fall. The bark is a light grey brown, becoming attractively ridged and warty with age. The flowers are inconspicuous. The reddish-purple fruit, a drupe, resembles a cherry on a long stalk and is well liked and dispersed by birds. CARE: Suited to a wide range of soil and moisture conditions,

hackberry performs best in full sun but tolerates moderate shade. USE: A smaller version of the elm, it is a good substitute as a shade tree, singly in smaller spaces and grouped in larger ones.

Closely related to American elm but free of Dutch elm disease, ‘Delta’ hackberry (Celtis occidentalis) is an ideal shade tree.

Red-osier dogwood (Cornus sericea, syn. C. stolonifera) Although often found growing wild on the edge of sloughs or bush in moist parts of the prairies, red-osier dogwood is surprisingly adaptable and moderately drought tolerant once established. Cornus is from the Latin corneolus, meaning horn and describes the hard wood, while sericea means silky, a reference to the hairy stems. The bark of this shrub was once used to cure mange (thus the common name, dogwood) as well as for dyeing and tanning. It has an irregular but somewhat mound-like form, with a height and width of 1.8 to 2.7 m (6–9 ft). The green leaves, opposite and simple, are prominently veined, oval and with pointed tips, turning red purple in fall. The small, white, flat-topped clusters of flowers in May and June give rise to bluish-white berries. The stems are dull red, becoming greyish with age and increased diameter (not unlike people).

Red-osier dogwood (Cornus sericea) has white flowers in the spring followed by bluish-white berries, red purple foliage in fall, and red stems through winter.

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Among the cultivars are: ‘Arctic Fire’ has a height and spread of 1 m (3 ft), with dark red winter twigs and a compact form. ‘Cardinal’ (1.8 m/6 ft in height and spread) is from Minnesota. The bark goes from green yellow in summer to brilliant red in winter. The dark green foliage changes to red purple in fall. ‘Isanti,’ another Minnesota introduction, is compact (1.2 m/ 4 ft in height, with a spread of 1.5 m/5 ft), dense and slowgrowing – a good choice for smaller spaces. Its dark green foliage changes to red purple in fall. ‘Kelsey’ is a dwarf dogwood (0.6–1 m/2–3 ft in height) with red stems in winter. ‘Silver and Gold’ is larger (1.8 m/6 ft in height and spread). It has variegated green foliage with a white margin and yellow stems and good winter value. CARE: Red-osier dogwoods grow well in full sun to partial

‘Arctic Fire’, a recent introduction of red-osier dogwood (Cornus sericea), has dark red winter twigs.

shade, with the best fall foliage colour in full sun. They tolerate a range of soils. Although they do better with even moisture, they are moderately drought tolerant once established. Water well until then. The oldest stems can be removed at ground level to promote new growth with a bright red stem colour to enhance your winter landscape. USE: They are well placed in shrub borders, as foundation plantings or used in naturalization, mass plantings and wildlife plantings.

Hazelnut (Corylus spp.) We can grow the large and hardy ‘Kerr’ hazelnut on the prairies thanks to the breeding work of Les Kerr, the last superintendant of the Sutherland Tree Nursery (now the Forestry Farm Park in Saskatoon). Corylus, the Greek name for hazelnut, is derived from the word korys, meaning helmet, while cornuta means horned. Both describe the small, edible nut that is enclosed by two leaf-like bracts (the green husk) that resemble a helmet and come to a point or horn. Both American hazelnut (Corylus americana) and beaked The beaked hazelnut (Corylus cornuta) is native to the dry woods of the prairies and is useful for naturalizing where its suckering will be an asset.

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hazelnut (C. cornuta) are native to the dry thickets and woods of the prairies. These large shrubs are about 1.8 to 2.7 m (6–9 ft) in height, upright and spreading. Multi-stemmed plants, they can become open and leggy with age, more so in shade. Because of

their suckering nature, they form a thicket over time. The alternate leaves are simple, irregularly toothed, with a pointed tip, turning yellow in autumn. Inconspicuous, yellow-brown, catkinlike flowers are borne in April. American hazelnut has bracts that barely cover the larger nuts (1.5 cm/0.5 in. in diameter), while the nut of the beaked hazelnut is enclosed. Male and female flowers occur on the same plant. Although it is widely stated that pollen from a different plant is required to produce edible nuts, a few isolated, single plants have been observed to produce abundantly, perhaps because of their hybrid nature. These small round nuts were once roasted or ground into flour. ‘Kerr’ is hardy, with a larger nut. It is believed to be a hybrid of C. avellana and either C. americana or C. cornuta. CARE: Grow hazelnuts in sun or partial shade on well-drained

soils with protection from wind. USE: Useful for wildlife plantings and naturalizing, hazelnuts should be placed where suckering will be an asset rather than a problem. The nuts are eaten by blue jays, bears and squirrels.

Cotoneaster (Cotoneaster spp.)

With its bronzy-red fall foliage, red berries, and herringbone pattern, it’s hard to beat ground cotoneaster (C. horizontalis) as a ground cover. In colder areas of the prairies, place it in a protected location.

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When I see a cotoneaster clipped as a formal hedge, I wonder why bother? Only a bit higher and wider in their natural form, an unclipped hedge saves an enormous amount of labour and is much less vulnerable to disease. Native to Asia, cotoneasters are a variable group of shrubs with small leaves, some of which turn scarlet in the fall and small red or dark blue berries. They range from low ground covers to taller shrubs. The genus name is from the Latin cotoneum, meaning quince, and refers to the quince-like appearance of the fruit. Ground cotoneaster (C. horizontalis var. perpusillus) is useful as a ground cover, but performs better in a more protected location. Up to 30 cm (12 in.) in height, it has a unique herringbone branching habit and shiny, dark green, rounded leaves. Hedge cotoneaster (C. lucidus) remains one of the best formal hedges available to prairie gardeners. It has a compact form and the small, dark green leaves turn a brilliant orange red in the fall when grown in full sun. Shaded plants are more yellow. The species name, lucidus, means shiny and describes the lustrous foliage. Untrimmed, hedge cotoneaster can attain a height of about 2.5 m (8 ft). The flowers are small and inconspicuous, the fruit dark blue to black.

Hedge cotoneaster (Cotoneaster lucidus) has been the hedge of choice in prairie towns and cities since the beginning of settlement. Its scarlet-orange fall colour is outstanding. Trimming is labour intensive.

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CARE: Cotoneasters prefer open locations in sun or shade

and well-drained soils. Hedge cotoneaster may need renewal pruning every decade or so. This involves cutting it to ground level in early spring before the leaves emerge. It is susceptible to silverleaf, a mycoplasma disease and fireblight, a bacterial organism. Both can be spread through pruning if tools are not disinfected with a 5 percent bleach solution or 70 percent isopropyl alcohol after each cut. Pear slugs can be a problem in mid to late summer and are best controlled with a strong jet of cold water from a garden hose. USE: While hedge cotoneaster is ideal for formal or informal

hedges or as a specimen plant in mixed borders, ground cotoneaster is valuable in a rock garden or cascading over a low retaining wall. They are valued for their colourful fruit and fall foliage as well as for food and cover for birds. ‘Arnold’ hawthorn (C. arnoldiana) has long been grown on the prairies. Beautiful but slow growing, it’s not for those who demand instant gratification.

Hawthorn (Crataegus spp.)

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Large shrubs or small trees resembling a crabapple in fruit and form, hawthorns are attractive in spring when in flower and in fall when in fruit. The fruit is generally red or dark brown and about 1 cm (0.5 in.) in diameter. The common name is a combination of the word haw, meaning a hedge or enclosure, for which they are commonly used in England and thorn, describing their armament: sharp, woody thorns. Many more species and selections were available a decade ago than are currently found at prairie garden centres. Native species such as Columbia hawthorn (Crataegus columbiana), Douglas hawthorn (C. douglasii) and cockspur hawthorn (C. crus-galli) are excellent for naturalizing, bank stabilization and wildlife habitat, but their availability is generally limited to nurseries specializing in native plant material. Among the ornamental landscape hawthorns are: ‘Arnold’ hawthorn (C. arnoldiana, syn. C. mollis), long grown on the prairies but very slow, is not a good choice for those who want instant gratification. An attractive small tree of 3.7 m (12 ft), it has single white flowers, protective thorns and large, scarlet fruits that are fleshy, tasty and were once used medicinally. It is easily pruned to a single trunk.

‘Toba’ hawthorn (C. mordenensis) combines fragrant, double pink flowers with diseaseresistance, a small size, and a thornless disposition.

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‘Snowbird’ (C. mordenensis), a seedling of ‘Toba,’ is said to be hardier and perhaps better suited to zone 2. Upright and round-headed, up to 4.6 m (15 ft) in height, it is thornless and has double white flowers in June, followed by bright crimson

berries. The deeply lobed, serrated, dark green foliage turns yellow orange in fall and is resistant to rust. ‘Toba’ hawthorn (C. mordenensis), a hybrid of ‘Paul’s Scarlet’ and C. succulenta, was introduced by the Agriculture Canada Research Station at Morden, Manitoba. It has glossy green foliage that turns yellow orange in fall and fragrant, double, pink flowers. Highly resistant to the foliage rust that plagues some hawthorns, its small size (4.3 m/14 ft in height with a 3.7 m/12 ft spread) and lack of thorns make it ideal for a smaller landscape. The trunk twists with age, giving it additional visual appeal. CARE: Hawthorns do well in full sun on a variety of soils as long

as drainage is adequate. USE: Its size, flowers and fruit make it an excellent but under-

used tree in the small urban yard or grouped in larger spaces. The native species are used in shelterbelt and wildlife plantings, where their sharp thorns preclude predators, providing food and protected nesting sites for birds.

Broom (Cytisus spp.) They are no longer used in the manufacture of brooms, but their flowers will sweep you away. Brooms are members of the pea family and mostly native to Europe. The genus name, Cytisus, is

Brooms should be much more readily available than they are. Prostrate bloom (Cytisus decumbens) is ideal for a rock garden with its low stature and bright yellow flowers in early spring.

the Greek name for clover, to which the trifoliate leaves are similar. The yellow, pea-like flowers are produced on new wood in summer. Used medicinally for centuries, the fresh seed pods are said to have intoxicating effects if ingested, but when roasted produce a beverage similar to coffee. Prostrate broom (Cytisus decumbens) is short (10–15 cm/4–6 in.) with a spread of up to 1 m (3 ft) and small leaves held close to the stem. It blooms in early summer with bright yellow flowers singly or in clusters along the stem. Spike broom (C. nigricans var. elongates), at 0.6 to 1 m (2–3 ft), has a profusion of yellow flowers on new wood during July and August. The species name, nigricans, meaning “black,” refers to the flowers that blacken when dried. CARE: Plant in full sun in well-drained soil. Deep rooted, they

are difficult to transplant once established. They thrive in infertile soil. USE: These brightly flowering shrubs are ideal in a mixed

border, shrub border or rock garden.

Spike broom (C. nigricans var. elongates), only 0.6 to 1 m (2–3 ft) in height, has a profusion of bloom in July and August.

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Diervilla, dwarf bush honeysuckle (Diervilla lonicera) Although native to the dry and rocky woodlands of Saskatchewan and Manitoba and with a wide natural range from Newfoundland to North Carolina, diervilla has only recently become commercially available. It’s a very welcome addition to our landscapes. It was named to honour M. Dierville, a French physician who travelled to Canada in 1699–1700 and first introduced this plant to European gardens. Both the species name, lonicera and the common name, dwarf bush honeysuckle, refer to its similarity to bush honeysuckle. It was long used by the Woods Cree to soothe sore eyes and to promote lactation. A low (0.6 to 1.2 m/2–4 ft), well-branched shrub with a suckering habit, it is grown mainly for its foliage. The simple, opposite leaves are tapered and long, with toothed margins with a fringe of short hairs. They emerge tinged with bronze in spring, are a glossy bronze green through summer and turn reddish orange in fall. Clusters of small, funnel-shaped, two-lipped yellow flowers are ‘Cool Splash’, a new introduction of diervilla (Diervilla lonicera) has attractive variegated foliage. It is worthy of trial in protected locations.

found in the leaf axils and stem tips in June and early July. The stems are green to reddish when young, maturing to grey brown. ‘Cool Splash’ (1 m/3 ft height and spread) has variegated greenand-white foliage. Not yet widely tested in the colder regions of the prairies, it is worthy of trial in protected locations. ‘Copper’ was selected for its more intense spring and fall colour. CARE: Diervilla will grow in a wide range of soils as long as

they are well drained, in partial shade to full sun. Water until established. Although drought tolerant, the more moisture it has, the faster it will spread. USE: Because of its tendency to sucker, it is extremely valuable for mass planting, as a ground cover under shade trees, for naturalization or for stabilizing banks or slopes. The tubular flowers are attractive to hummingbirds.

Russian olive and wolfwillow (Elaeagnus spp.)

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Members of this genus have attractive silver foliage, small silver berries and fragrant but inconspicuous flowers. They are particularly attractive when placed next to shrubs with purple red foliage. Elaeagnus is from the Greek word eleia meaning oil, a reference to the fruit, which somewhat resemble olives. With retained silver foliage and fruit through winter, Russian olive (Elaeagnus angustifolia) adds to the fourth season of our landscape and is extremely drought tolerant.

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Russian olive (Elaeagnus angustifolia) is to dry areas what willows are to wet sites. Both have a large and billowy “willowy” appearance. The species name, angustifolia, means narrow leafed.

Native to Europe and Asia, Russian olive is a graceful, finetextured tree, ranging in height from 4.5 to 7.5 m (15–25 ft). Leaves, twigs, flowers and fruit are all covered in minute grey scales, giving it a silvery appearance. The long, narrow leaves are retained through most of the winter, lending it a permanent “hoarfrosted” look. The inconspicuous yellow and silver flowers, borne in early June, are highly fragrant and are followed by inedible olive-like fruit. Thorny and non-thorny forms are available. CARE: Russian olives do best in full sun in well-drained soils.

They are salt tolerant but will not tolerate flooding or poor drainage. Some clones may suffer winter injury. USE: These trees are used as specimen or shade trees, in

screen plantings and in shelterbelts. The silver foliage contrasts well with evergreens and shrubs with red and purple foliage. Birds consume the fruit.

The tiny yellow and silver flowers of Russian olive (E. angustifolia) are inconspicuous but very fragrant.

Wolfwillow (E. commutata) is native to the prairies and casts its sweet scent along fence lines in May, bringing nostalgic memories of walking to school to those who grew up in rural areas. An upright and sometimes leggy shrub of up to 2.5 m (8 ft), it suckers freely, soon forming thickets. Place it with care. The branches and leaves are covered with silvery scales. The fragrant, tubular, four-petalled flowers are inconspicuous, silver outside and yellow within. The small, silver fruit is dry and mealy. ‘Silverscape’ (‘Jefmorg’) is a sterile hybrid of Russian olive and wolfwillow of only 1.8 m (6 ft) in height and with less suckering than wolfwillow. ‘Zempin’ is an improved selection, widely available in Europe but much less so here in Canada. About 3.5 to 4.5 m (12–15 ft) in height, it has very dark (almost black) branches and intense, contrasting silver foliage. It suckers freely. CARE: Plant in full sun in a variety of soils. It is saline tolerant. USE: Wolfwillow is used for wildlife plantings, naturalization, reclamation and on banks and slopes to control erosion. It provides food and cover for birds and is a bee nectar source. It is infrequently found grafted onto Russian olive rootstock (to prevent suckering), making it valuable in a shrub border, especially if planted where one can smell the fragrance in spring.

Wolfwillow (E. commutata), native to the prairies, casts its sweet scent along fence lines in May.

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Ash (Fraxinus spp.)

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Ash are large, tall and long-lived trees with attractive, opposite, pinnately compound leaves. Because of their deep root systems, they do not compete with lawns or understory plantings. The genus name is from the Roman name for a European ash species, while the common name, ash, is derived from the Norse aska, meaning man. Why? The Norse god Odin was believed to have carved the first man from an ash branch. ’Mancana’ ash (Fraxinus mandshurica ‘Mancana’) has to be one of the toughest and most adaptable prairie trees. Introduced by the Agriculture Canada Morden Research Centre and available since the mid 1990s, it has a dense oval to rounded canopy, lustrous green compound leaves (each with nine to ten leaflets) and turns gold in the fall. With a mature size of about 12 m (40 ft) in height and a 7.5 m (25 ft) spread, it is fast growing and tolerates drought, wind and poor soil. It is a male, seedless selection. CARE: Plant in full sun in a variety of soils. They are extremely

drought tolerant. USE: ‘Mancana’ ash make excellent specimen, boulevard or shade trees and have been used extensively in shelterbelts. ‘Mancana’ ash (Fraxinus mandshurica) is one of the most drought tolerant prairie trees.

Green ash (F. pennsylvanica var. subintegerrima) is ideal as a specimen tree in the middle of a lawn because its deep root system does not compete for moisture with the grass. Native to Manitoba and Saskatchewan, it is hardy and long lived and turns an attractive gold in fall. Fast growing, it has an upright, oval form and reaches about 18 m (60 ft) in height, with a spread of 5.5 to 6 m (18–20 ft). Male and female flowers are borne on separate trees. The single-seeded samaras produced by the female trees are retained through the winter and consumed by birds. It has a deep, fibrous root system that is able to tap subsoil moisture. ‘Bergeson’ is vigorous and fast growing, upright with an oval crown, turning a pleasant yellow in fall. ‘Foothills,’ a seedless cultivar, was selected for its performance in the Chinook belt surrounding Calgary. ‘Patmore’ is a male clone from Brandon that leafs out earlier in the spring than most other green ash and retains its foliage longer into the fall. It is upright with an oval crown.

Many of the newer cultivars of of green ash (Fraxinus pennsylvanica var. subintegerrima) are outstanding.

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‘Prairie Dome’ (‘Leed’) is oval to rounded in shape, very dense, also turning a nice yellow in fall.

‘Prairie Spire’ (‘Rugby’), selected by Dale Herman from North Dakota State University, is narrower and more upright, turning an intense yellow in fall. CARE: Green ash do well in full sun or partial shade in a variety

of soils. They are salt tolerant. They are occasionally attacked by cankerworms, lygus bugs, leaf rollers and, in female trees, gall mites. The emerald ash borer may become a major problem. Prominent frost cracks on the main trunk are not unusual but are seldom damaging. USE: They are excellent as shade or boulevard trees and in shelterbelts.

Dyer’s greenwood, broom (Genista tinctoria) A small shrub that puts on a tremendous show of bright yellow flowers, broom is more dependable than forsythia in

Dyer’s greenwood or broom (Genista tinctoria) is easily incorporated into a mixed border or rock garden.

colder regions of the prairies and should be much more widely available. Native to Europe and western Asia, broom was used commercially as a dye plant as early as the 1600s, hence the botanical and common names (tinctoria means used in dying). A low, upright shrub of 1 m (3 ft), it has bright yellow, pea-like flowers in June and bright green leaves. Both the tiny leaves and the bright green branches photosynthesize. CARE: Broom is well adapted to infertile, well-drained soils and

performs best in full sun. It is difficult to move once established. USE: This is a useful replacement for forsythia in areas of the prai-

ries where the latter is not dependable. It is easily incorporated into an informal shrub border, mixed border or rock garden.

Siberian salt tree (Halimodendron halodendron)

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In and out of flower, Siberian salt tree has a lovely, even delicate, appearance when seen from afar. Its spiny nature, however, combined with a prodigious ability to procreate through seed and suckers, limits its use to highway and reclamation plantings. The genus name means tree of the seashore. The species name is a combination of halo (salt) and dendron (tree). Perhaps a bit repetitive, but the names say it all: a tree that grows along the coast of Siberia, well accustomed to the salt spray of the sea. A member of the pea family and related to caragana, the salt tree has fine-textured, silver leaves and spines and forms a 1.8 to 2.7 m (6–9 ft), upright, spreading and somewhat leggy shrub. The leaves are pinnately compound, each with four sessile leaflets

Although both saline and drought tolerant, the Siberian salt tree (Halimodendron halodendron) suckers and seeds profusely.

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and a terminal leaflet modified to form a spine. In autumn, the leaflets fall, but the central spine-tipped vein remains on the tree. The pale lilac-pink flowers, which appear in midsummer, are pea-like and quite ornamental. They are followed by a brownish-yellow pod that remains on the tree through winter. The salt tree seeds and suckers profusely. It is sometimes grafted onto Caragana arborescens to reduce suckering and make it more acceptable as an urban planting. CARE: Siberian salt tree will grow on any well-drained soil in

full sun and is salt tolerant. USE: This is a good plant for naturalization, reclamation on

The pea-like, pale lilac-pink flowers of the Siberian salt tree (H. halodendron) are pretty but the plant’s spiny nature is not.

dry soils or highway plantings where winter salt spray would damage many other woody plants. It is also useful near septic mounds where few other shrubs will thrive.

Sea buckthorn (Hippophae rhamnoides)

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This large shrub has many positive attributes, including the ornamental and nutraceutical value of its fruit, but also a few negative ones: a prodigious ability to sucker and downright dangerous thorns. Place it carefully and select the cultivar wisely. Don’t be lured into thinking that “the experts” have its suckering nature all wrong. After five or six quiet and quite well-behaved years, it will suddenly appear, well armed and all over your landscape. This “expert” speaks from experience... Both the botanical and common names make reference to this plant’s resemblance to common buckthorn (Rhamnus). A large, upright shrub of up to 3.7 m (12 ft), sea buckthorn is native to Europe and Asia. The Russian name oblepeekha translates as “glued on berries,” alluding to the difficulty involved in their harvest. Once picked, they are made into excellent jellies, preserves and a liqueur, as well as a very tasty gelato. It has a long and continuous history of medicinal use in Europe. Its narrow, silver leaves and twigs terminate in sharp thorns. The flowers are small, yellow and inconspicuous. The small, bright yellow, orange or red fruit is held close to the branches and persists over winter. It is planted extensively in Russian shelterbelts and processed as a juice and pulp because of its high vitamin C content. Plants with fewer thorns have been selected to make harvesting less difficult. Sea buckthorn (Hippophae rhamnoides) is another tough, well armed shrub with an almost frightening ability to sucker and cover ground.

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‘Dorana’ is small with less suckering, heavy fruiting and easier picking. ‘Frugana’ is strongly upright in form, with light yellow fruit ripening in late August.

‘Harvest Moon’ (# 6582 ) from PFRA at Indian Head, is virtually thornless, compact and has good yields. The large, yellow orange fruit is easily picked. ‘Hergo,’ from Germany, is a heavy cropper with light orange fruit. ‘Hikul’ is the most dwarf (1.2 m/4 ft) and dense variety. ‘Indian Summer’ has medium-sized, light orange fruit and is useful both for fruit and as a windbreak. ‘Leikora’ is one of the most ornamental of the cultivars, with a broad, bushy form. It has large orange fruit that is late ripening. ‘Orange September,’ also from PFRA, Indian Head, is similar to ‘Harvest Moon’ but with a higher sugar content. CARE: Sea buckthorn is both drought and saline tolerant and

should be grown in full sun. It is dioecious, so both male and female plants are needed (1 male: 7 female) to produce fruit. It is wind-pollinated. Once established, it suckers profusely, more so if the roots are disturbed by tilling. USE: This is a shrub for farmyards, acreages, shelterbelts, highway

allowances and marginal land reclamation. Its suckering habit precludes its use in smaller urban settings. The retained fruit lends it excellent winter landscape value. It is useful as a wildlife planting, providing habitat for sharp-tail grouse, Hungarian partridge and pheasant. Magpies eat the berries. It provides cover and nesting sites for small songbirds. The fruit is used for jelly.

Juniper (Juniperus spp.)

The fruit of sea buckthorn (H. rhamnoides), borne on female plants, has a high vitamin C content. The jelly tastes apricot-like.

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Although junipers are superficially similar to cedars (Thuja), there’s a world of difference in the way these two genera respond to hardship. Junipers are among the most drought tolerant of the evergreens. Cedars demand even moisture, wind protection and soil amended with organic matter. Many hardy species and cultivars of juniper are available, varying from ground covers to columnar forms of up to 4.5 m (15 ft). Their leaves are in the forms of scales, awls or needles. Colours range from green to gold to blue to silver, with some variegation. The male cones are very small and inconspicuous, while the female cones mature to a dark blue, berry-like fruit with a waxy, powdery coating or “bloom.” This fragrant fruit is used to flavour gin. Common juniper (Juniperus communis) is native to much of North America, Europe and Asia. Indigenous peoples used the fruit both decoratively and as an insect repellent. Early settlers

Common juniper (Juniperus communis) is native to the prairies as well as Europe and Asia. It has many forms and is generally extremely drought-tolerant.

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used it as a coffee substitute. Extremely variable in form and height, on the prairies it is usually about 1 m (3 ft) and tends to turn purple with the onset of cooler fall weather. It has sharp, awl-shaped needles with a white band down the centre of the upper side. The needles are arranged in whorls of three. ‘Depressa Aurea,’ 1 m (3 ft) in height with a spread of 2.7 m (9 ft), has golden-yellow spring foliage and is much hardier than the more commonly available golden pfitzer. ‘Effusa’ is compact, 30 cm (12 in.) in height with a spread of 1 m (3 ft). It is a rich green-blue selection with a white band on the upper side of the needles. It holds its colour into winter. Creeping juniper (J. horizontalis) is native to the Canadian prairies and generally up to 30 cm (12 in.) in height. The leaves are scale- or awl-like, soft textured and feathery. Many turn purple in winter. ‘Andorra’ is bright green, turning plum in fall, with a dense, more upright form, 30 cm (12 in.) in height with a Juniperus communis ‘Depressa Aurea’ is a form of common juniper with outstanding foliage, especially in spring when the new growth is a bright gold. It should be much more widely available.

1.8 m (6 ft) spread. ‘Bar Harbor’ is a blue-green selection from Maine, becoming purple in winter. A mat-like ground hugger of only 30 cm (12 in.) in height with a 1.8 m (6 ft) spread, it has blue berries. ‘Blue Chip’ is bright blue, turning slightly mauve in winter. It is low and mounding, 30 cm (12 in.) in height with a 1.5 m (5 ft) spread. ‘Blue Prince’ is an intense powder steel blue, retaining this colour in winter. It has a spreading, prostrate form, 15 cm (6 in.) in height with a 1.2 m (4 ft) spread, with cascading potential. ‘Blue Rug’ (‘Wiltonii’) is another selection from Maine, with intense silver-blue foliage and blue berries. Dense, low and spreading (15–20 cm/6–8 in. in height with a 1.5 m/ 5 ft spread), it is fast growing. ‘Hughes’ is silver blue, vigorous, low and spreading, 30 cm (12 in.) in height with a 2.7 m (9 ft) spread.

‘Andorra’ (Juniperus horizontalis) has graced prairie gardens for many years. Bright green through summer, it turns a plum colour in fall. Only 30 cm (12 in.) in height, it can reach a spread of 1.8 m (6 ft).

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‘Icee Blue’ (Monber), a sport of ‘Wiltonii,’ is an intense silver blue with very minute, tight foliage and a low trailing habit, reaching only 10 cm (4 in.) in height with a 1.2 m (4 ft) spread. ‘Mother Lode,’ about 10 cm (4 in.) in height with a spread

of 1 m (3 ft), is another sport of ‘Wiltonii,’ similar but with golden variegated foliage. ‘Prince of Wales’ is bright green, turning purple in winter. Selected in Alberta, it’s a real ground hugger, forming a dense carpet only 15 cm (6 in.) in height with a spread of 1.8 m (6 ft). ‘Wapiti’ is dark green, becoming purple in winter. It is low and spreading, 30 cm (12 in.) in height with a spread of 2.7 m (9 ft). ‘Youngstown’ (‘Plumosa Compacta Youngstown’) is bright green, becoming purple in fall, with arching, tightly branched foliage, reaching 30 cm (12 in.) in height with a spread of 1.5 m (5 ft). Savin juniper (J. sabina) is native to Europe, but many selections have proven hardy on the prairies. It is typically arching, upright and vase-shaped and 0.6 to 1 m (2–3 ft) in height. The scale-like leaves are not prickly and their bright green colour is retained through winter.

‘Blue Rug’ juniper (J. horizontalis), also called ‘Wiltonii,’ has intense silver blue foliage with blue berries. It’s dense, low, spreading, and fast growing.

‘Arcadia’ is a bright grassy green, 0.6 m (2 ft) in height with a spread of 1.8 m (6 ft), with an arching, soft, dense, layered appearance. ‘Blue Danube’ is a bright blue green, semi-erect, 0.6 m (2 ft) in height, broad and spreading to 1.5 m (5 ft). ‘Broadmoor’ has rich green foliage and a dense, low mounding form, 0.3 m (1 ft) in height and a spread of 1.5 m (5 ft). ‘Buffalo’ is bright green, maintaining good colour through winter, with small green berries. It forms a wide, spreading ground cover, 0.3 m (1 ft) in height with a spread of 1.8 to 2.7 m (6–9 ft). ‘Calgary Carpet,’ a selection of ‘Arcadia,’ is bright green, dense and layered, 0.3 m (1 ft) in height with a 1.5 m (5 ft) spread. ‘Monard’ (‘Moor-Dense’) is a bright green, denser and flatter form of ‘Broadmoor’ with a tiered branching habit, 0.3 m (1 ft) in height with a 1.5 m (5 ft) spread. ‘Skandia’ is an older variety with bright green foliage and green berries that resists winter browning. It has a compact, low, spreading form, 0.3 m (1 ft) in height with a spread of 1.5 m (5 ft). ‘Tamariscifolia’ is green, tightly branched, low and mounding

‘Arcadia’ (Juniperus sabina) is one of the oldest and best of the savin junipers; vase-shaped and a bright grassy green with an arching, layered look.

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(0.6 m/2 ft in height, 1.5 m/5 ft spread) and more shade tolerant than other selections. Rocky Mountain juniper (J. scopulorum) varies in form, from broadly pyramidal to narrow and columnar and attains heights up to 6 m (20 ft). The foliage can be green, silver or blue grey. Scopulorum means of rocks or cliffs and refers to its native habitat, the Rocky Mountains of Western Canada. ‘Blue Arrow’ is an intense steel blue with a narrow, tight, columnar form, 3.7 m (12 ft) in height with a spread of 1.5 m (5 ft). ‘Blue Heaven’ (sometimes called ‘Blue Haven’) is the same A dependable older variety, ‘Skandia’ (Juniperus sabina) has a low and compact form.

height, blue and pyramidal with a 1.5 m (5 ft) spread. More open than many, it benefits from shearing. ‘Cologreen’ is a bright forest green, dense and coneshaped, 3.7 m (12 ft) in height with a spread of 1.2 m (4 ft) at its base. ‘Medora,’ introduced from North Dakota in the 1950s, is blue green with a narrow columnar form, 2.7 m (9 ft) in height, with a spread of only 1 m (3 ft), dense and slow growing. ‘Moonglow’ is silvery blue, dense, with a broad rounded pyramidal form, 3.7 m (12 ft) in height with a spread of 1.8 m (6 ft). ‘Sky Rocket’ is, as the name suggests, rocket-shaped, greenish-blue and probably the narrowest of the hardy Rocky Mountain junipers, reaching 4.5 m (15 ft) in height with a spread of only 1 m (3 ft). ‘Wichita Blue’ is extremely tough and hardy, silver blue, with a broadly pyramidal form, 3.7 m (12 ft) in height with a 1.8 m (6 ft) spread, that benefits from shearing. CARE: Junipers prefer a well-drained soil and require full sun

to maintain a dense form. This is especially true of the blue grey selections. All are tough plants and perform well on a south or west exposure where cedars do not. Some Rocky Mountain and common junipers are alternate hosts for saskatoon-juniper rust. Branches infected with rust should be removed by pruning as soon as the rust is noticed.

‘Medora’ (Juniperus scopulorum) has been in prairie gardens for over half a century.

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USE: Depending on their size and form, junipers are used in mixed or shrub borders, for massing, screening, as ground covers or understories, to hold difficult slopes or banks or in a rock garden. The berry-like cones add to their landscape value. They provide cover and food for birds.

Siberian larch (Larix sibirica)

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If space allows, Siberian larch should be high on your wish list. It is a large, fast-growing tree, up to 18 m (60 ft) in height, that retains a pyramidal form and almost perfect symmetry throughout its life. The branches arch gracefully down, turning up at their tips. As the name implies, this species is native to Siberia and northeast Russia. It is better adapted to dry conditions than our own tamarack (L. laricina). The needles are soft, bright green and flexible. On newer growth, they are single and spirally arranged along the branch. On older growth, they are in dense clusters on short pegs. Like other larches, the Siberian larch is deciduous, losing its needles each fall. In spring, the new growth is early and a lovely soft green. Fall colour is an outstanding golden yellow. The male cones look like catkins and wither once the pollen is shed. The erect female cones resemble small wooden rosettes and persist on the naked branches throughout the winter, maturing in one season. ‘Oasis,’ 14 m (45 ft) in height with a 6 m (20 ft) spread, is a new introduction selected by Rick Durand of Manitoba. It holds its foliage much later into the fall, remaining green

Siberian larch (Larix sibirica) should be high on your wish list if you have the space for a large tree.

longer and becoming golden later in the season. CARE: Plant on well-drained soil in full sun. USE: Because of its size, the Siberian larch is well suited as a specimen tree in larger urban yards, acreages and farm plantings. It is also used in shelterbelts, where it establishes quickly. The fall colour contrasts well with evergreens and the purple red foliage of other trees and shrubs.

Honeysuckle (Lonicera spp.)

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While many gardeners are familiar with the Tartarian bush honeysuckle, there are other interesting but lesser known honeysuckle species that are well worth seeking out. Named for Adam Lonitzer, a German herbalist and botanist (1528–1586), honeysuckles are fast-growing shrubs of 0.6 to 3.7 m (2–12 ft). They are valued for their flowers (usually pink, but also white, yellow or red) and their berries (mostly red, but also orange, white or blue). The flowers are produced in pairs in the leaf axils. The bark is thin and peeling. Leaves are simple and opposite, generally grey green to blue green. Sweetberry or honeyberry honeysuckle (Lonicera caerulea var. edulis), native to Asia, is a species with edible blue fruit. The Latin name says it all: caerulea means blue and edulis

Hascaps are a new generation of sweetberry honeysuckle (Lonicera caerulea) and are known for their superior taste and productivity.

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edible. George Bugnet of Edmonton introduced selections from Siberia almost half a century ago, including one he named after himself. A newer generation of cultivars introduced by Bob Bors of the University of Saskatchewan is vastly superior in taste and productivity. Called haskap in their native Japan, they generally resemble an elongated blueberry with tender skin, a waxy bloom and a dark red interior. The compact bushes are about 1.5 m (5 ft) in height, with a 1 m (3 ft) spread. The pairs of cream-coloured flowers are among the earliest to bloom in spring, with fruit ripening in late June. It is used in ice cream, jam, pie filling and wine. Among the 2007 University of Saskatchewan introductions are: ‘Berry Blue,’ a Russian selection, is a good pollenizer for the University of Saskatchewan selections. ‘Borealis’ has the best flavour and largest fruit size of the cultivars. ‘Tundra’ has firm fruit suitable for commercial production. The bracted honeysuckle (L. involucrata), native to the prairies, has paired tubular yellow flowers in the leaf axils.

To ensure pollination and fruit, plant two different cultivars with an overlapping bloom period within bee-flying distance of each other. Bracted honeysuckle (L. involucrata) is a large shrub (1.2 m/4 ft in height and spread) native to the woods and boreal forests of the prairie provinces. Bracts surround the paired, tubular yellow flowers found in the leaf axils; these later form purple-black fruit, which may be poisonous. The leaves are simple, oval and bright green. Amur honeysuckle (L. maackii) is a large, upright shrub of 2.4 to 2.7 m (8–9 ft) with paired, fragrant white flowers and dark red fruit that matures a bit later than most. Native to Manchuria and Korea, it was introduced from Asia via Lautaret, France, by Skinner’s Nursery in Manitoba in 1929. It’s a beautiful shrub that deserves much wider availability and use. Sakhalin honeysuckle (L. maximowiczii sachalinensis) is another lovely but relatively unknown honeysuckle. With a height and spread of 1.8 m (6 ft), it is unusual among the taller honeysuckles in that its branches and foliage descend right to ground

Relatively unknown, the Sakhalin honeysuckle (L. maximowiczii sachalinensis) has foliage right to the ground, red purple flowers and red fruit.

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level, avoiding any hint of legginess. The foliage emerges with a coppery sheen, turning dark green in summer and golden in fall. More tolerant of shade than many, it has a rounded form, purplish branches, red purple flowers and red fruit.

White or morrow honeysuckle (L. morrowii) is a rare species well worth seeking out. A dense, broadly rounded shrub of 2 to 3m (6–9 ft) spread, it has grey to blue green foliage that hugs the ground, creamy flowers and red orange berries. Tartarian honeysuckle (L. tatarica), native to central Asia, is a large, tough and drought-tolerant shrub with a height and spread of up to 2.7 m (9 ft). The two-lipped flowers, all but hiding the blue green foliage in June, are in red, pink or white. The fruit is red, orange or yellow. In the 1980s, Tartarian honeysuckles, once a common sight over the prairies, were decimated by infestations of an aphid inadvertently imported from Russia. It caused abnormal fasciated and purplish tip growth resembling witches’ broom. Dieback and eventual death followed. The Tartarian honey-

Morrow honeysuckle (L. morrowii), a rare species with creamy flowers.

suckles below are resistant to this insect. ‘Arnold’s Red,’ an older variety that proved resistant to the aphid, has the darkest pink (almost red) flowers of any cultivar and red berries. ‘Cameo,’ with white flowers and orange fruit and ‘Flamingo’ with pink flowers and red berries, are from Boughen’s Nurseries of Valley River, Manitoba. ‘Honeyrose’ (sometimes listed as ‘Honey Rose,’ L. korolkowii) sports rosy-red flowers with distinctive yellow anthers and red fruit. ‘Sunstar,’ a selection of Sunstar Nurseries in Edmonton, has white flowers and red fruit. European dwarf or fly honeysuckle (L. xylosteum) gets its common name from the fact that flies often sip the nectar

Tartarian honeysuckle (L. tatarica) typically have pink or reddish flowers.

from its inconspicuous yellow flowers. It has little or no fruit and is grown mainly for its compact size, globe shape and dense, grey green foliage. The bark shreds or peels with age. The infrequent, dark, wine-coloured berries are believed to be poisonous. Native to Europe and Asia, the species itself is unavailable, but several selections are sold as dwarf or formal hedge material or for massing. ‘Clavey’s Dwarf,’ (1.2 m/4 ft, height and spread) is mounded, with light, grey green foliage and may have a few flowers. ‘Emerald Mound’ is compact, dense and forms a low mound of blue green foliage, 0.6 m (2 ft) in height, with a spread of 1.2 m (4 ft). Its juvenile growth habit means it requires little or no shearing when used as hedging.

‘Arnold’s Red’ (L. tatarica) has the darkest pink (almost red) flowers of any cultivar.

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‘Miniglobe’ is a hybrid of L. x xylosteoides. Compact and globe-shaped, it has a height and spread of 1 m (3 ft), dark, blue green foliage and no flowers. It was released from the Agriculture Canada Research Station at Morden in 1981. CARE: Honeysuckles are tough, drought-tolerant shrubs, well adapted to prairie conditions and requiring little maintenance. They do best in full sun or partial shade on well-drained soils.

Most of the cultivars of European dwarf honeysuckle (L. xylosteum) are small and compact.

USE: The taller honeysuckles are useful on larger lots, acreages and farmsteads as hedging, in mixed or shrub borders and in shelterbelts. They do not lend themselves to small urban settings or more formal landscapes. The dwarf honeysuckles are used as low hedging, in mixed borders and for massing. Honeysuckle is a nectar plant for butterflies and the fruit is consumed by birds and other wildlife.

Flowering crabapple (Malus spp.) Although their bloom is synonymous with spring, crabapples have an extended season of landscape value thanks to their often highly coloured foliage and fruit. Small, dense, low-headed trees of up to 7.5 m (25 ft), flowering crabapples are ideally suited to smaller urban landscapes or grouped in larger ones. Relatively fast growing, their lifespan is about forty years or longer. The flowers are white, pink or red. Leaves range from green to purple, generally with good fall colour. By definition, the fruit of crabapples is 4 cm (1.5 in.) or less in diameter. Those Rosybloom crabapples (Malus x adstringens) have pink to red flowers and purplish leaves.

termed “rosyblooms” (M. x adstringens) have pink to red flowers and purplish leaves. The Siberian crabapple (M. baccata) is upright in form and about 7.5 m (25 ft) in height with white flowers. Although somewhat susceptible to fireblight, the white flowers contrast well against those of the rosyblooms. It has been used in the breeding of flowering crabapples to give them greater hardiness. When making your selection, consider how much space you have and which colour of flowers and foliage you would prefer. If fireblight or scab are problems in your area, select a tree that is resistant. Do you want a crabapple that retains its fruit over winter, attracting birds? Tidy gardeners are not fond of those with fruit that drops early. Among the cultivars available to prairie gardeners are: ‘Almey,’ at 5.5 m (18 ft) high with a spread of 3.7 m (12 ft), has an

Siberian crabapples (M. baccata) have white flowers.

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open canopy, deep rose flowers with white centres, burgundy foliage in spring that becomes bronze green and maroon fruit.

‘Big River’ has pink flowers, greenish-bronze foliage and purple black fruit, combined with a tight pyramidal form reaching 4.5 m (15 ft) with a spread of 1.8 m (6 ft). ‘Dolgo’ is upright (up to 5.5 m/18 ft in height) and spreading to 3.7 m (12 ft), with white flowers, green foliage and bright red, edible fruit. It’s an old (1917) introduction from South Dakota and still going strong. ‘Gladiator,’ a recent Rick Durand selection, has upright branching, glossy bronze-purple foliage, bright pink flowers, small reddish-purple fruit and improved resistance to apple scab. It reaches 5.5 m (18 ft) in height with a spread of 2.7 m (9 ft). ‘Kelsey’ (4.5 m/15 ft in height with a spread of 2.7 m/9 ft) has semi-double to double dark red purple flowers, purple foliage becoming copper green and small persistent purplish-red fruit. ‘Makamik,’ introduced in 1921, has a rounded, spreading form

‘Shaughnessy Cohen’ has cherry-red buds, fuchsia-pink flowers and small reddishpurple fruit.

of 7.5 m (25 ft) in height with a 5.5 m (18 ft) width, rosy-red flowers, bronze green foliage and retained purple fruit. ‘Pink Spires,’ a Les Kerr selection, has pink flowers, red purple foliage and a narrow upright form of 4.5 m (15 ft) in height with a spread of 2.7 m (9 ft). ‘Prairiefire,’ with an upright, rounded form of 5.5 m (18 ft) in height and spread, has purple-red flowers, small persistent fruit and disease resistance. In colder regions of the prairies, place in a sheltered location. ‘Radiant,’ with fireblight resistance, is a compact, symmetrical, rounded tree of 4.5 m (15 ft) in height with a spread of 3.7 m (12 ft), with single pink flowers, purple spring foliage turning to green and bright red fruit.

‘Spring Snow’, has pink buds opening to white flowers and no fruit.

‘Red Splendor’ has a large open form with a height and spread of 4.5 m (15 ft), deep rose-pink flowers, green foliage and retained red fruit. ‘Royalty’ is upright and rounded with a height and spread of 4.5 m (15 ft), the darkest purple foliage of any crabapple and orange tints in fall. It has reddish-purple flowers and dark red fruit. It is susceptible to fireblight. ‘Rudolph’ is a symmetrical, upright tree of 4.5 m (15 ft) with a rounded crown of 3.7 m (12 ft), red flowers, bronze foliage and persistent red fruit. ‘Selkirk,’ introduced by Agriculture Canada’s Morden Research Station in 1962, is vase-shaped, reaching 6 m (20 ft) in height with a spread of 5.5 m (18 ft). It has single, pink flowers,

Crabapple fruit is by definition 4 cm (1.5 in.) or less in diameter.

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burgundy spring foliage turning to bronze green and red, persistent fruit. Hardy and vigorous, it is resistant to fireblight. ‘Shaughnessy Cohen,’ with a height and spread of 6 m (20 ft), has cherry-red buds, fuchsia-pink flowers and small reddishpurple fruit. The foliage is coppery-bronze in spring, turning dark green in summer and yellow in fall. ‘Spring Snow,’ introduced by Bert Porter in 1967, has an upright, oval form, reaching a height of 6 m (20 ft) with a 3.7 m (12 ft) spread. It has pink buds opening to white flowers, glossy green foliage and no fruit. Ideal for fussy gardeners. ‘Starlite’ is resistant to both apple scab and fireblight. It is 7.5 m (25 ft) in height with a spread of 4.5 m (15 ft). A profusion of white flowers in spring is followed by tiny red fruit that is retained through winter, giving it four-season landscape value and providing food for birds – a bonus for gardeners who dislike messy fruit cleanup. ‘Strathmore’ has a narrow, vase-shaped form, 3.7 m (12 ft) in height with a spread of 2.7 m (9 ft). It has dark red flowers, red purple fruit and red foliage that deepens in fall. ‘Thunderchild,’ at 4.5 m (15 ft) in height with a spread of ‘Starlite’ is a newer introduction with a profusion of white flowers, and resistance to apple scab and fireblight.

3.7 m (12 ft), is compact and upright, with dark pink flowers, purple foliage and small red fruit that drops in fall. It is resistant to fireblight but susceptible to scab in some regions. CARE: Once established, crabapples do well on the prairies,

especially in more sheltered sites. Water well for the first four to five years until their root systems are established. They prefer a deeper soil with adequate drainage and full sun. If scab or fireblight are a persistent problem in your area, select diseaseresistant cultivars. USE: Flowering crabapples are excellent trees for smaller yards and when grouped are equally suited to more expansive landscapes. They are used as boulevard trees, for screening, in shelterbelts and as wildlife plantings, where they provide cover and are an excellent winter food source for waxwings and other fruit-eating birds.

American hop hornbeam, ironwood (Ostrya virginiana) Here is a unique native tree with many characteristics in its favour: shade tolerance, drought tolerance once established, an ‘Thunderchild’ crabapple has dark pink flowers, purple foliage and is resistant to fireblight.

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ideal size for a smaller landscape, interesting fruit, shaggy bark and good fall colour. Unfortunately in this age of instant gratification, it is slow to become established and is seldom available

at nurseries or garden centres. Once established, however, it makes excellent growth. Related to birch, it forms part of the forest understorey on well-drained ridges in its native southeastern Manitoba. The genus name, Ostrya, is from the Greek ostrys, meaning shell and describes the seed pods. The species name, virginiana, indicates the southern part of its natural range, while the common names refer to the resemblance of the seed pods to hops and the hardness of its wood. Once used for hand tools, it has the densest wood of all Canadian trees. An attractive small tree to 7.5 m (25 ft), it has a wide, rounded crown. The alternate leaves are simple and oval with serrated margins, turning yellow gold in fall. The male flowers are catkins, while the female flowers develop into 5 cm (2 in.) seed pods that resemble hops. The grayish-brown bark of mature trees peels in strips, giving it a slightly shaggy appearance. CARE: It will grow in sun or shade on a wide range of soils from

moist to dry as long as they are well drained. USE: Excellent as a small shade tree.

Mockorange (Philadelphus lewisii) Its landscape value is limited to that week or so when it’s in bloom, but it is worth planting for that singular explosion of

Native to Manitoba, American hop hornbean or ironwood (Ostrya virginiana) is seldom seen in our gardens although it makes a lovely, shade tolerant small tree.

fragrant, white flowers. Philadelphus is from the Greek phrase for brotherly love, while the species name honours Captain Meriwether Lewis of the Lewis and Clark Expedition. This erect and spreading shrub of 2 to 2.4 m (7–8 ft) produces a profusion of single white flowers on arching branches in June. Their fragrance and form resembles that of orange blossoms (thus the common name). Almost unrivalled in full bloom, once flowering is over it is just a plain green shrub. Because the flower buds of mockorange are formed in the fall, they are sometimes killed above the snow line during severe winters in unsheltered locations. The two hardiest and most dependable cultivars are: ‘Blizzard,’ introduced by Beaverlodge Nursery in Alberta many years ago, has superior flower-bud hardiness and is a profuse bloomer. It reaches 1.5 m (5 ft) or more in height, with a spread of 1 m (3 ft). ‘Waterton,’ native to the Waterton Lake area of Alberta, has single white (albeit scentless) flowers to the base, arching branches and an upright rounded form, 2.4 m (8 ft) in height with a spread of 1.5 m (5 ft).

‘Blizzard’ mockorange (Philadelphus lewisii) has superior flower-bud hardiness.

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Other cultivars for zones 3 and 4 and protected areas of zone 2 include: ‘Aureus,’ is a P. Coronarius selection with bright yellow foliage (1 m/3 ft in height and spread). ‘Galahad,’ with single white flowers (1.2 m/4 ft in height and spread). ‘Miniature Snowflake,’ with double white flowers (1 m/3 ft in height and spread). ‘Minnesota Snowflake,’ with double white flowers (1.8 m/6 ft in height and spread). ‘Snowbelle,’ with double white flowers (1.2 m/4 ft in height and spread). CARE: Plant in full sun or light shade in a range of soils. Water Golden mockorange (Philadelphus coronarius ‘Aureus’) needs a protected location in zone 2.

until established. Once the root system has developed, it is quite drought tolerant. USE: Plant mockorange where you can take advantage of its one-time prolific bloom and its scent, in a mixed or shrub border.

Ninebark (Physocarpus opulifolius) Ninebarks provide landscape value over an uncommonly long season: colourful yellow or purple foliage through summer, intensifying in fall; creamy-white flowers in spring; and deep red seed pods in late summer. A number of excellent hardy cultivars have been introduced in the last decade. One wonders how we landscaped without them. An upright, spreading shrub of up to 2.7 m (9 ft) with arching branches, ninebark is found from Quebec to Virginia. The common name alludes to the cinnamon-brown exfoliating bark, which peels to reveal a number of layers (though not necessarily nine). The genus name is from the Greek words physa, meaning bladder and karpos, fruit, a reference to the attractive, inflated red seed pods produced in late summer. The species name, opulifolius, refers to the resemblance of its leaves to those of the European cranberry (Viburnum opulus). All of the cultivars have creamy flowers and red seed pods. They differ in foliage colour and size. ‘Amber Jubilee’ ninebark (Physocarpus opulifolius) has new growth of various shades of yellow and orange.

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‘Amber Jubilee,’ named to honour Queen Elizabeth’s visit to Manitoba in 2010, is a cross of ‘Diabolo’ and ‘Dart’s Gold.’ While the older foliage remains a lime green, the new growth produces shades of yellow and orange in summer, turning

purple in fall. It reaches 1.8 m (6 ft) in height, with a spread of 1.2 m (4 ft). ‘Centre Glow’®, a Minnesota introduction, emerges in spring with vibrant yellow green foliage, becoming red with a glowing yellow centre (2.7 m/9 ft height and spread). ‘Coppertina,’ another hybrid of ‘Dart’s Gold’ and ‘Diabolo,’ has orange-copper foliage in spring that becomes a vibrant red in fall. It reaches 2 m (7 ft) in height with a spread of 1.8 m (6 ft). ‘Dart’s Gold’ is a small, compact cultivar of 1.5 m (5 ft), with a spread of 1 m (3 ft). It has golden foliage.

‘Center Glow’ ninebark (P. opulifolius) has yellow green foliage in spring, later becoming red with a glowing yellow centre.

‘Diabolo’®, from Germany, has deep purple foliage, becoming almost iridescent red purple in the fall. It is 2.4 m (8 ft) in height with a spread of 1.8 m (6 ft). ‘Luteus’ has greenish-yellow foliage, the yellow being most pronounced in early spring. It has a height and spread of 2.4 m (8 ft). ‘Nugget,’ from South Dakota State University, is compact and dense but larger (1.8 m /6 ft in height, with a spread of 1.2 m/4 ft). The foliage emerges yellow, becoming lime-green in summer and yellow in fall. ‘Summer Wine’TM has been described as a condensed form of ‘Diabolo’ with more deeply cut foliage. It emerges in spring a deep purple, becoming purple red in fall. A hybrid of P. ’Nanus’ and ‘Diabolo,’ it has a dense, compact form of 1 m (3 ft) and is excellent for smaller spaces.

‘Dart’s Gold’ ninebark (P. opulifolius) is a small, compact cultivar of only 1.5 m (5 ft) with golden foliage.

CARE: Drought tolerant, ninebarks perform best if grown in

full sun on well-drained soils. In shade, the yellow foliage of the golden ninebarks is much less pronounced. They may be subject to lime-induced iron chlorosis in soils with a high pH. USE: Place them in mixed or shrub borders or use them as foundation plantings. The yellow or purple foliage is an excellent contrast with other shrubs.

Spruce (Picea spp.) We tend to picture spruce as large, stately conifers that dominate our landscapes, but in fact they vary from 1 to 30 m (3–100 ft) in height. While some are at home in a rock garden or mixed border, others are ideal for shelterbelts. Colour ranges from silver blue to dark green and drought tolerance from moderate to extreme. Spruce needles are four-sided (square in cross-section) and

‘Summer Wine’ ninebark (P. opulifolius), is a smaller version of ‘Diabolo’.

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feel “bumpy” when rolled between your fingers. They are singly and spirally arranged on the branches. Newer growth always appears brighter and more deeply coloured because of the waxy coating or bloom on the needle surface. This is eventually worn away by the action of wind, rain and grit. Branches are arranged in whorls with a single whorl produced each year. New growth ceases by early summer. The genus name, Picea, is from the Latin word for pitch pine, which is derived from pix, meaning pitch or resin. There are many species and cultivars from which to choose. Norway spruce (Picea abies), from central and northern Europe, has a wide distribution and a number of distinct Spruce (Picea spp.) needles are singly and spirally arranged on the branches.

forms. Once widely planted on the prairies, the species is seldom offered today, possibly because of its large size (30 m/ 100 ft). However, two smaller forms are readily available as well as a grafted weeping form. Nest spruce (P. abies ’Nidiformis’), a dwarf form of Norway spruce, is dense, globe shaped with a flat top and extremely eye-catching and ornamental. Slow growing and long lived, it has a height and spread of only 1 m by 1.5 m (3 x 5 ft) at maturity. It has bright green, sharply pointed needles. ‘Ohlendorfii’ Norway spruce (P. abies ‘Ohlendorfii’) is another excellent smaller form of Norway spruce. If nest spruce has a symmetry about it, ‘Ohlendiorfii’ is the awkward, lumpy cousin with a delightful free-form growth habit when young. It eventually grows to a dense, pyramidal, upright shrub of 2.4 m (8 ft). It also has bright green, sharply pointed needles. CARE: Plant in full sun to partial shade on well-drained soil.

These are very drought tolerant once established. USE: Excellent in a mixed border, rock garden, shrub border or for foundation plantings. Black Hills spruce (P. glauca var. densata)

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although

sometimes difficult to find, is an excellent conifer with a dependable track record and should be much more widely available. A variety of white spruce, it was introduced by the Black Hills Nursery of South Dakota in 1920. The species name means glaucous, referring to the needles. Densata means dense and describes its form. Black Hills is a denser and more compact form of white spruce, with short, dark green needles and a narrow pyramidal form. It is better ‘Ohlendorfii’ Norway spruce (Picea abies ‘Ohlendorfii’).

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adapted to prairie conditions than the species. It makes rapid growth while young, reaching an ultimate height and spread

of 12 m by 4.5 m (40 x 15 ft). CARE: Plant in full sun on a range of soils. It is resistant to win-

ter desiccation and is very drought tolerant. USE: Use it as a specimen tree or as a grouping, as screen plant-

ings and in shelterbelts. It provides food and cover for birds. Colorado spruce (P. pungens)

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is a large (up to 18 m/60 ft)

and somewhat formal evergreen with a lifespan of over a hundred years. A small blue spruce in a nursery pot is very much like a puppy at the SPCA – cute and begging for adoption. If your yard is relatively small, think twice about the species and instead consider one of the smaller cultivars. Colorado spruce takes space. Native to the Rocky Mountains, Colorado spruce has a pyramidal form and needles that vary from green to blue grey. The species name, pungens, means sharp pointed, a reference to the extremely sharp needles. This is not a huggable tree. Those sold as “blue spruce” are usually budded or grafted selections and therefore somewhat more expensive than trees propagated from seed. The root system is shallow, spreading and close to the soil surface, making it difficult to grow other plants or a lawn under or immediately adjacent to a spruce. Mulching is a much better option. Male cones are small, yellow and located on the lower branches. Once they have shed their pollen in spring, they

Black Hills spruce (Picea glauca var. densata) is amazingly drought tolerant.

disintegrate. The female cones are much larger and on the ends of branches in the upper part of the tree. They mature, disperse seeds and fall within a year. The following cultivars are smaller than the species and have done well on the prairies. Their size is more proportional to smaller urban lots than the species and they are good for mixed and shrub borders. ‘Bakeri’ has a compact, pyramidal form with a height and spread of 3.7 m by 1.8 m (12 x 6 ft) and intense blue needles. ‘Fat Albert’ has an irregular, pyramidal form, 4.5 m (15 ft) in height with a 2.7 m (9 ft) spread and dense blue foliage. ‘Glauca Globosa’ is globe shaped (1.5 m/5 ft in height and spread), slow growing and an intense blue. Its size suits mixed borders. ‘Glauca Pendula’ is graceful, eye-catching, extremely

Dwarf blue spruce (Picea pungens ‘Glauca Globosa’) is ideal for borders and foundation plantings.

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ornamental and a lot tougher than its weeping appearance would suggest. The main stem is generally staked to a height of 1 to 2.7 m (3–9 ft) and then allowed to weep, giving it a variable height and spread. ‘Hoopsii’ has a dense, irregular but pyramidal form and silver-blue foliage. About half the size of the species, 9 m (30 ft) in height with a spread of 1.8 m (6 ft), it is a good compromise for smaller spaces. ‘Iseli Fastigate’ has a narrow, almost columnar form, 3.7 m (12 ft) in height with a spread of 1.5 m (5 ft), with steelblue foliage. ‘Montgomery’ has a rounded bottom spreading to 1.8 m (6 ft) and a more upright top reaching 3.7 m (12 ft) and dense silver blue foliage. Weeping forms of evergreens, such as this Norway spruce (Picea abies) are extremely attractive.

CARE: Fully hardy and adaptable to a wide range of soils, Colorado spruce are drought tolerant but seem to perform better on heavier soils. They require full sun. In sheltered locations with poor air circulation they are sometimes infested with spider mites, which can be controlled by spraying the interior of the tree with a strong jet of cold water from a garden hose. Cooley spruce gall aphid and spruce budworm are occasionally a problem.

Prune spruce as little as possible, allowing the lower branches to extend to the ground as nature intended. “Shaving the legs” of a spruce is unsightly and unnecessary. To control weeds, mulch with grass clippings, chopped straw, post peelings, leaves or other organic material and allow the needles and cones to add to the mulch as they fall. Tilling damages roots as well as the lower branches. USE: Consider the ultimate mature height and spread of a spruce before planting it. The species is one of the largest trees available to prairie gardeners and is better suited to more expansive landscapes. Large spruce are used as screening, specimen trees and in shelterbelts. They provide food and excellent winter cover for birds. Smaller selections are good for mixed borders and foundation plantings.

Pine (Pinus spp.) If your soil is light, sandy and well drained, your evergreen of If you want the appearance of a Colorado blue spruce (Picea pungens) but lack the space, ‘Montgomery’ is a good option.

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choice is pine. Pines grow naturally on light, sandy soils and are well suited to the prairie xeriscape. Pines also provide cover and food for birds. They are browsed by deer. Their needles, in bundles of two, three or five, are roughly

triangular in cross-section and arranged spirally on the whorled branches. Male and female cones are on the same tree. The male cones are found on young branches at the base of the tree and disintegrate after releasing pollen. When transplanting pines, ensure that the root ball is not disturbed. Exposing the fine, fibrous roots to air and sun may doom the transplant to failure. Jack pine (Pinus banksiana)

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is the most widely dis-

tributed pine in Canada. The species name honours Sir Joseph Banks, a British horticulturist, but their form is more reminiscent of a painting by the Canadian Group of Seven. Native to our northern forests, the jack pine gets by on very little. To early European settlers and modern farmers alike, jack pines signalled poor soil and unproductive farmland. When grown in the open, they are typically gnarled and twisted, with a broad, open form. In the forest, they are taller and straighter due to competition with other trees for light and space. They reach up to 12 m (40 ft) and can live for 150 years. Jack pines have dark green to yellowish-green needles that are sharply pointed and in bundles of two, but slightly splayed within the bundle. The cones have no prickles. Most remain closed and persist on the tree for ten to twenty years until triggered to open by the heat of fire. The root system is wide spreading and fairly deep, usually with a taproot. CARE: They tolerate poor, sandy or gravelly soils as long as

drainage is adequate and they receive full sun. USE: Jack pines are useful for naturalization on poor soils. They make an interesting specimen tree where a twisted, gnarled appearance is desired, but are better left at the lake than in a formal landscape. Swiss stone pine (P. cembra)

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Jack pines (Pinus banksiana) tend to have an open, somewhat twisted and gnarled form.

has a narrow, upright,

columnar to pyramidal form, reaching a height of 12 m (40 ft). The long, soft needles are in bundles of five. The bark is smooth and light grey, becoming scaly with age. Relatively slow growing, they are extremely hardy, resistant to winter sunscald injury, very attractive, trouble-free and sadly underused. Swiss stone pine is native to the European Alps and into Asia. One of the highlights of a recent holiday to northern Italy was to unexpectedly find myself in what I was almost positive was the middle of a forest of Swiss stone pine. When I was told that the Italian common name for the trees was cembra, I grinned from ear to ear to have had the good fortune of, however fleetingly, inhabiting its native habitat.

Pine needles are in bundles of two, three or five.

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CARE: Place in full sun on well-drained soil. They are more tolerant of wet clay soils than other pines. USE: Excellent in a mixed border or as a specimen tree, espe-

cially in a smaller landscape. Lodgepole pine (P. contorta var. latifolia)

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will be

familiar to anyone who has explored the Cypress Hills of Saskatchewan and Alberta. It is also native to the Rocky Mountains. The species name, contorta, means twisted and may be a reference to the gnarled branches or the twisted needles. The common name refers to the use of the long, straight trunk in teepees and lodges by Indigenous peoples, who also used the resin for waterproofing canoes, baskets and moccasins. Exceeding 18 m (60 ft) in height, it has a lifespan of up to two hundred years. The needles are dark green to yellow green, in bundles of two, twisted and sharply pointed. The cones persist on the tree for ten to twenty years. The root system consists of a taproot and spreading lateral roots. CARE: Plant in full sun on a wide range of soils. Swiss stone pine (P. cembra) is extremely drought tolerant.

USE: Lodgepole pine is useful in a large landscape, for

screening, as a specimen tree and in shelterbelts. Limber pine (P. flexilis)

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is similar to the Swiss stone

pine but slightly smaller. It is also a good candidate as a specimen tree in a smaller landscape. Both its botanical and common names indicate the flexible nature of the young branches. Native to British Columbia, Alberta and North Dakota, it reaches only 9 m (30 ft) and is often multi-trunked. Although moderately slow growing, it can live for several hundred years. The bark is light grey and very smooth. The needles are blue green and in bundles of five. The cones mature in winter, when they open to release seeds. CARE: Adapted to dry, rocky, exposed sites, limber pines grow

best in full sun on a variety of soils, as long as drainage is adequate. USE: They are excellent as specimen trees, especially in smaller

yards where a larger conifer would be overwhelming. Mugo pine (P. mugo) are quite variable in height (as a look Lodgepole pine (P. contorta var. latifolia) is useful in a large landscape.

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around an older prairie neighbourhood will tell you), from less than 1 m (3 ft) to 5.5 m (18 ft) or more and their form ranges from low and spreading to almost upright. It is probably

with a sense of relief that you’ll find most of the cultivars at nurseries today are of the shorter, more compact type. The species name, mugo, is from the old name used in the Tyrol Mountains of Austria, one of the areas to which it is native. The bright green needles are in bundles of two and persist for about five years. Branches are brownish grey with bumpy bits that once held the needle bundles. Among the cultivars are: ‘Mops,’ with a height and spread of 1 m (3 ft) is somewhat globe shaped, dense and mounded. ‘Pumilio’ is low and rounded, 1.2 m (4 ft) in height with a spread of 1.8 m (6 ft). ‘Slowmound’ is dense, low and mounded with a height and spread of 1 m (3 ft). Mountain pine (P. uncinata), at 7.5 m (25 ft) with a spread of 3.7 m (12 ft), is the single-stemmed, tree form of mugo pine. CARE: Although they do well on a wide range of soils, they need regular watering until they are established (about five years) and their root system is well developed. After that, they are quite drought tolerant. If you have an older mugo that needs containment, it can be pruned annually once the “candles” have fully elongated each spring. Be sure to leave at least 1 cm of the new growth.

Limber pine (P. flexilis) has light grey bark and blue green needles in bundles of five. It makes a good specimen tree for a smaller yard.

USE: Depending on their form, place mugo pines in a shrub or mixed border, rock garden, mass planting or use them as foundation plantings. Rocky Mountain yellow pine (P. ponderosa var. scopulorum)

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is a case where obtaining a plant with the correct Latin name is important. While ponderosa pine (P. ponderosa) is a great tree in every way, it has an enormous natural range, from British Columbia southward and unless you’re gardening in a sheltered microclimate, it generally does not do well on the prairies. Pinus ponderosa var. scopulorum, the Rocky Mountain yellow pine, a subspecies, is a smaller, more compact version of the ponderosa pine. It is native to the Black Hills of South Dakota and is hardy in most of the prairie region. So read the small print on the tag! The species name, ponderosa, means heavy and describes the wood, while scopulorum means of the mountains. It reaches 18 m (60 ft) in height with a straight trunk and a broadly pyramidal form with a 5.5 m (18 ft) spread. It has a deep

Although extremely variable in form and size in the wild, most mugo pines (P. mugo) found in nurseries tend to be under 1.2 m (4 ft) and are excellent in borders or as foundation plantings.

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and wide-spreading root system. The needles are generally in bundles of three, dark green to yellow green and sharp pointed. Each scale on the cone ends in a rigid, sharp prickle. Cones mature in fall and open to release seeds over winter. The bark is dark grey. CARE: Grow in full sun on a wide range of soils. USE: This pine makes an excellent specimen tree or grouping appropriate to a larger landscape. Scots pine (P. sylvestris)

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is the pine to grow if you

garden on light sandy soil and want a generous return for moderate effort. It has foxy orange peeling bark and offers year-round habitat for birds. Rocky Mountain yellow pine (P. ponderosa var. scopulorum), a subspecies of ponderosa pine, is hardy in most of the prairie region.

Scots pine is native from Scotland through Europe and into Russia and Siberia. The species name, sylvestris, meaning woods, makes reference to these vast tracks of forest. A medium to large (up to 18 m/60 ft), fast-growing conifer, it is dense when young, but the whorled branches become more open and the form more flat-topped with age. In unsheltered locations, the trees sometimes bend with the prevailing winds. The slightly twisted needles are held in bundles of two and are usually retained for three to five years. The male cones are yellow and disintegrate after shedding pollen. The female cones mature in their second autumn and release seeds through late winter and early spring. During the first warm days of spring, the cones pop open audibly as the seeds are released. The root systems are moderately deep and wide spreading, particularly on sandy soils. CARE: Scots pine is adapted to full sun and a wide range of

soils, but seems particularly well suited to sandy soils. Trees grown from seed from its northern range are perfectly hardy; those from seed collected from southern Europe and many cultivars are not. Two very occasional problems are sapsuckers (a woodpecker that damages the bark with a series of geometrically aligned holes) and borers (insects that bore into the wood, sometimes causing the top of the tree to break off). In thirty years, I’ve only encountered these problems once. USE: Scots pine is useful as a specimen tree in urban or rural

Scots pine (P. sylvestris) is your conifer of choice if you garden on sandy soil.

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settings. Because of its deep taproot, it seldom competes with lawns or flower beds as would a spruce. Its open, less geometrical form, lends itself to a more informal landscape. It is used as screening and in shelterbelts.

Swedish columnar aspen (Populus tremula ‘Erecta’) If I hadn’t lived with this one for three decades, I wouldn’t have termed it drought tolerant. I don’t think it’s been given supplemental water for twenty-five years, yet it’s growing in pure sand, hiding a utility pole by my driveway. Swedish columnar aspen was a selection found in the wild in Sweden and introduced in the 1920s. With a very narrow columnar form (15 m/50 ft in height with a spread of only 1 m/3 ft), its branches are narrow and upright and held very close to the trunk. The alternate leaves are round and dark green with wavy margins and flattened petioles, giving it an ability to “tremble” with the slightest breeze. The bark is greyish brown with a white bloom. A male clone, it does not produce seed, but does have the ability to sucker prodigiously if the roots are damaged by digging or tilling. There is an urban legend that a tree’s upper visible form reflects its root system. Not true! The root system of this narrow tree is very shallow and very wide-spreading. If it is disturbed by trenching, you’ll find suckers coming up from as far as 9 m (30 ft) away. CARE: Plant in full sun on well-drained soil. USE: Excellent for an accent or for screening (especially utility

poles!).

Potentilla (Potentilla fruticosa) While detractors may mutter, “What, another introduction?,”

Swedish columnar aspen (Populus tremula ‘Erecta’) has a narrow form and a height of 15 m (50 ft).

potentilla remain one of the basics of our shrub and mixed borders. To their credit, they’re generally of a size compatible with a smaller urban lot, with a great flush of bloom in June and less profuse flowering through the remainder of the summer. Their foliage is neat and tidy. Add to this their hardiness and the great drought tolerance of many of the cultivars. Potentilla is from the Latin potens, power, a reference to the ancient medicinal uses of some species. Illa means small. Thus we have a small plant of great power – certainly a tough one with a long period of bloom. Native to the prairies, the species has deep yellow, buttercuplike flowers, up to 2.5 cm (1 in.) in diameter, which are borne in small clusters at the ends of branches throughout the summer. The grey green, compound leaves consist of five leaflets (thus the other common name though not much used today, cinquefoil, meaning five leaves). It forms a bushy shrub of 0.3 to 1 m (1–3 ft) and grows well on sandy soils. The hybrid potentillas are a group of small (mostly up to 1 m/3 ft) flowering shrubs with loose and shredding bark and

‘McKay’s White’, an older potentilla introduction, has creamy-white flowers, soft grey-green foliage, and a dwarf mounding form.

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white or yellow flowers. Although newer cultivars are being bred with pink, red and peach-coloured flowers, as well as double flowers, these do not tend to be as drought tolerant. The following cultivars have proved themselves drought tolerant once established: ‘Abbotswood,’ with a height and spread of 1 m (3 ft), has large white flowers produced in profusion and small blue green leaves. ‘Coronation Triumph’ has clear, bright yellow flowers, small, soft green leaves and a dense mounding form of 1 m (3 ft). ‘Fargo’ (‘Dakota Sunspot’) is a compact shrub of 0.6 m x 1 m (2–3 ft) with a profusion of large, deep golden blooms throughout the summer. ‘Gold Drop’ is dwarf in every way. It has small, lemon-yellow flowers; very small, bright green leaves; and a compact form, reaching only 0.6 m (2 ft) in height and spread. An older cultivar, ‘Abbotswood’ potentilla (P. fruticosa) has large white flowers on plants with a height and spread of 1 m (3 ft).

‘Goldfinger’ has large, bright yellow flowers; dark green leaves; and a tall, mounded growth habit of 1 m (3 ft) in height and spread. ‘Gold Star’ is a dwarf shrub with a height and spread of only 0.6 m (2 ft) and a profusion of large, bright yellow flowers and dark green foliage. ‘Jackman,’ an upright and vigorous older variety with a height and spread of 1 m (3 ft), has yellow flowers and large, dark green leaves. ‘Katherine Dykes,’ another older introduction, has soft light yellow flowers, silver grey foliage, arching branches and is fast growing, with a mature height and spread of 1 m (3 ft). ‘McKay’s White’ has creamy-white flowers, soft grey green foliage and is dwarf and mounding, with a height and spread of 0.6 m (2 ft). ‘Sutter’s Gold,’ at 0.6 m (2 ft) in height and spreading to 1 m (3 ft), has large, bright yellow flowers and silver foliage. ‘Yellow Gem’ is a newer dwarf introduction from the University of British Columbia that is very hardy. It has yellow flowers with

‘Yellow Gem’ potentilla (P. fruticosa), a newer introduction, combines a low mounding form and grey green foliage with yellow ruffled petals. It’s ideal for a rock garden or border.

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ruffled petals, grey green foliage and a low, mounding form, reaching only 0.3 m (1 ft) in height with a spread of 0.6 m (2 ft). CARE: Plant in full sun in well-drained soil and water until

established. Plants are weaker and less floriferous in the shade. Older plants can look scruffy in spring. Wait until they begin

to leaf out to determine which branches are alive. The dead branches can then be (somewhat painstakingly) pruned out as close to ground level as possible. Another option is to prune the entire plant to ground level about every three or four years. It’s easier but not as character-building for the gardener. USE: Because of their small size and long blooming period, potentillas are useful as foundation plantings, in shrub or mixed borders, rock gardens, informal groupings and for massing as ground covers.

Cherry prinsepia (Prinsepia sinensis)

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This is a tough shrub for inhospitable sites and it is not without ornamental value. It leafs out very early and the red fruit is retained through winter. It is an upright and spreading shrub of 1.8 to 2.7 m (6–9 ft), characterized by a loose form and arching branches, but its chief claim to fame is its very stout thorns, making it exceptionally well suited as a barrier planting or impenetrable hedge. The genus was named after James Prinsep (1799–1840) a scholar of coins and early scripts of India. Sinensis means of China – it is native to Manchuria. The leaves are light green, long, narrow and lance-shaped. The inconspicuous small yellow flowers are followed by attractive, somewhat flattened, cherry-like red fruit.

Because of its thorny nature, cherry prinsepia (Prinsepia sinensis) is ideal for “traffic control” or a barrier planting.

CARE: Prinsepia is fully hardy and grows in a variety of soils

in full sun or shade. It is drought tolerant and untroubled by insects or disease. USE: Because of its thorny nature, it is excellent for “traffic control” or a barrier planting. Leave it in its natural form as part of an informal shrub border. The fruit is sometimes used for jelly, but if left on the plant through winter it is consumed by birds.

Plums and cherries (Prunus spp.) This is a large genus of trees and shrubs, many of which are both hardy and drought-tolerant, as well as highly ornamental. We grow some for their early spring flowers, others for their fruit and some for their attractive purple foliage. Their leaves are opposite and generally oblong to lance-like in shape. Prunus is derived from the Latin common name for a plum tree. ’Royal Pink Beauty’ plum (Prunus spp.), though of unknown origin, is a lovely small tree or large shrub that should be

‘Royal Pink Beauty’ (Prunus spp.) is a gem of a small tree with deep rose single flowers in early spring.

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much more widely planted and available. It was received by Boughen’s Nursery in Valley River, Manitoba, in a shipment of apricot seeds from Manchuria in 1939. It is absolutely gorgeous! Vivid deep rose blooms cover it in early spring before the leaves emerge and it is fully two weeks earlier than the double flowering plum (Prunus trilobum ’Multiplex’). It is approximately 2.5 m (8 to 9 ft) in height with arching branches and small green leaves. CARE: Plant in full sun on well-drained soil. It is extremely

drought tolerant once established. USE: A versatile small tree or large shrub suited for all land-

scapes, from a condo to an acreage, it can be used as a focal point, massed or as part of a shrub or mixed border. Cistena cherry or purple leafed sandcherry (P. x cistena)

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was almost alone among the shorter shrubs in providing purple foliage for prairie gardens until the introduction of A standout for its purple foliage, cistena cherry or purple leafed sandcherry (Prunus x cistena) is an old favourite in prairie gardens.

barberries and the newer ninebarks. More than a century after its introduction, it remains one of my favourites. Professor N. E. Hanson of the State Experimental Station in Brookings, South Dakota, selected this low, multi-stemmed cross of P. pumila and P. cerasifera ‘Atropurpurea’ in 1909. Cistena is perhaps derived from the Sioux word for baby, a reference to its dwarf form. Sometimes killed back to the snow line in colder regions, it regrows about 1 m (3 ft) each season and is valued principally for its attractive red purple foliage, producing pink to white flowers only occasionally. In zone 3 and 4 it may reach 1.5 m (5 ft). CARE: Plant in full sun in well-drained soil. Once established,

little water and no fertilizer are required. It appears to overwinter better on a lean, mean diet, especially when going into dormancy in fall. Be particularly careful not to overfertilize with nitrogen. If dieback occurs, simply prune off the dead branches. USE: With its purple leaves, cistena cherry is an excellent addi-

tion to a shrub or mixed border. Its size makes it suitable to a smaller yard or it can be massed in a larger landscape. Mongolian cherry (P. fruticosa)

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is native from Europe

to Siberia and into Mongolia and has been in cultivation for Flowers of cistena cherry (P. x cistena) can be white or pink.

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over three hundred years. The species name, fruticosa, indicates its shrubby nature.

It has an upright, spreading form, up to 1.5 m (5 ft) in height, with dark green, glossy leaves, small white flowers and small, bright red, edible sour cherries. CARE: Plant in full sun on well-drained soil. USE: Plantings of Mongolian cherry should be limited to rural areas where its ability to sucker prodigiously can be an asset rather than a liability. Use it as a wildlife planting, massed or for reclamation and highway plantings. Dwarf sour cherries (P. kerrasis), relatively new and based on breeding by Les Kerr in the 1940s, were further developed by Bob Bors at the University of Saskatchewan. They have opened a whole new dimension in fruit available to prairie gardeners. Not only are they delicious, hardy, disease- and insect-resistant and easy to grow, but they are also extremely drought tolerant once established. They are good both fresh and processed and, in spite of their name, the newer releases are far from “sour.” Lovely white blooms precede the fruit. Heights average about 1.8 m (6 ft) with the spread depending on the suckering of the individual cultivar.

The new dwarf sour cherries (P. kerrasis) are both edible and ornamental. ‘Carmine Jewel’ is among the best.

‘Carmine Jewel,’ the first in the series, released in 1999, is a black cherry with small pits and consistently high productivity and few suckers. Many still consider it among the best. The Romance series was released in 2004: ‘Crimson Passion’ is dark red, very sweet, excellent for fresh eating and good for processing, but with low vigour and smaller yields. It has no suckers. ‘Cupid’ is black to dark red with the largest fruit of the series. It has good flavour for fresh eating and it blooms a week later than the others. It has few suckers. ‘Juliet’ has dark red fruit with excellent flavour for fresh eating and is good for processing. It is very productive, with moderate vigour and few suckers. ‘Romeo’ has dark red-black fruit and is very similar to ‘Carmine Jewel’ but ripens later. Very flavourful, it is good for fresh eating and processing and is one of the best for juice. It is also one of the most productive. ‘Valentine’ has medium red fruit and is a tart type suited for pies; it has some suckering.

‘Valentine’, one of the dwarf sour cherries (P. kerrasis) released in 2004, has medium red, tart fruit suitable for pies.

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CARE: Plant in full sun on a variety of soils. They are drought

tolerant once established. USE: Both ornamental and edible, the new dwarf sour cher-

ries are at home in a fruit garden as well as a mixed or shrub border. Depending on your space, keep their suckering characteristics in mind when you make your selection. ’Princess Kay’ flowering cherry (P. nigra ‘Princess Kay’) is a selection of our native wild Canada plum discovered in northern Minnesota by Kay Nylund, for whom it is named. It has fragrant, fully double, snowy white flowers that emerge in early spring prior to the leaves. Because the flowers are sterile, there will never be messy fruit to contend with. A small, upright tree reaching to 4.5 m (15 ft) in height with a spread of 2.7 m (9 ft), it is ideal for all landscapes. It has attractive, shiny black bark and the dark green foliage turns ‘Princess Kay’ (P. nigra), from northern Minnesota, is a small upright tree with fully double white flowers ideal for any landscape.

various shades of yellow orange in the fall. CARE: Hardy to zone 3a, ‘Princess Kay’ is best placed in a protected location in colder areas of the prairies. Plant in full sun on well-drained soil. It is drought tolerant once established. USE: Ideal as a focal point in a smaller yard, it can also be part of a mixed or shrub border or grouped in larger landscapes. Mayday tree (P. padus var. commutata) is one of the loveliest spring-flowering trees available, though its susceptibility to black knot fungus limits its use through much of the southern prairies. I’ve seen it used extensively in northern Alberta and have been amazed (and a wee bit jealous) at its vigour, beauty and freedom from disease in areas such as Grande Prairie. The mayday tree leafs out in early spring and is generally in full bloom by mid-May, hence the common name. Native to northern Europe and Asia, it is fast growing and vigorous, up to 9 m (30 ft) in height. It is usually grown as a single-trunked, oval- or round-headed tree, but is sometimes seen in clump form. The true mayday is said to be non-suckering, but because it readily hybridizes with chokecherries (to which it is closely related), the progeny have varied characteristics. The fragrant white flowers and drooping clusters of edible black fruit of mayday and chokecherries are similar.

The susceptibility of the mayday tree (Prunus padus var. commutata) to black knot, a fungal disease, has severely limited it use in the prairies, but there are lovely specimens in northern Alberta.

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CARE: Maydays grow on a range of soils and prefer full sun. If

black knot occurs, affected branches should be pruned out. In areas where black knot is endemic, it’s easier not to grow it. USE: Use as a shade tree, in shelterbelts and wildlife plantings. It provides food and cover for birds.

Pincherry (P. pensylvanica)

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is native to much of North

America, including the Canadian prairies. The species name, pensylvanica, refers to Pennsylvania (or William Penn’s woods), also part of its native range. The common name is a reference to the size of the fruit. When first planting my bare, five-acre, bromegrass pasture in 1980, I began with pincherry, chokecherry, saskatoon and golden currant, knowing they were dependable, fast growing, hardy and drought tolerant. They’ve never disappointed me and I still use them where the going is tough. Pincherries grow to about 4.5 m (15 ft) in height and are considered a large shrub or small, round-headed tree. The smooth bark is red-brown. The lance-shaped leaves are bright green in summer and turn a bright yellow orange in fall. A great abundance of small white flowers is produced in round clusters in May, followed by small red cherries, which are excellent made into jelly. The newer introductions have been selected mainly for the larger size and higher quality of their fruit. ‘Jumping Pound’ bears red fruit but is grown primarily

‘Mary Liss’, a selection of pincherry (P. pennsylvanica), has large mild fruit with good flavour and tender skin.

as an ornamental. It is a small tree, 2.5 to 3 m (8–10 ft) in height, with a lovely weeping form. It should be more widely available. ‘Lee #4,’ with a height and spread of 1.5 m (5 ft), produces large fruit on long racemes. ‘Mary Liss’ was selected for its large, mild fruit, with good flavour and tender skin. It reaches a height of 4.5 m (15 ft). CARE: Pincherries do well in full sun on well-drained soils. Most

sucker freely, so place them carefully. Root injury from cultivation (tilling or digging) encourages suckering, while mulching somewhat reduces it. Use: The improved cultivars are excellent in an informal shrub border and as specimen trees, either singly or grouped. The species is used in shelterbelts, for naturalization, reclamation and in wildlife plantings. Birds eat the fruit. Branches may be cut and brought indoors in February for winter forcing of blooms. Russian almond (P. tenella)

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is native from Europe to

Siberia. It is a small shrub up to 1 m (3 ft) in height, with a strong suckering habit. The single pink flowers open in early May before the simple, dark green leaves emerge. Tenella means dainty, an apt description of Russian almond in full

A small shrub (1 m/3 ft) with a strong suckering habit, Russian almond (P. tenella) is lovely in full flower in early spring.

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flower. The “almond” of the common name is a flat, inedible fruit covered with soft, silky hairs. The muckle plum (Prunus x nigrella ‘Muckle’), a hybrid of the Canada plum (Prunus nigra) and Russian almond, is 2.7 m (9 ft) in height, with an upright, oval form. The bright red buds produce an intense display of bright pink, single flowers in spring before the leaves emerge. CARE: This tough shrub grows on a wide variety of soils in sun or partial shade, though it blooms less in shade. USE: Although useful in informal shrub borders and as a ground cover, its tendency to sucker limits its use in a formal or well-manicured landscape. Nanking cherry (P. tomentosa) is a lovely early flowering shrub with the bonus of edible fruit. Plant two or more.

Nanking cherry (P. tomentosa) is another tough Prunus, lovely in spring and with the bonus of producing edible fruit much used in jelly. An upright shrub of 1 to 1.2 m (3–4 ft), Nanking cherry is native to China and Japan. It produces white to pink flowers in early May prior to the appearance of its dull green, wrinkled foliage. The word tomentosa describes the silky hairs that cover both sides of the leaves. The bright red fruit is about 1.5 cm (0.5 in.) in diameter. CARE: Nanking cherries grow in various soils in full sun and

are drought tolerant once established. Shelter from the wind is beneficial to fruit production. Cross-pollination is required, so plant two or more plants in close proximity. USE: Nanking cherries have ornamental value when in flower and fruit. They are used in shrub or mixed borders and in wildlife plantings. They provide food and cover for birds and make excellent jelly. Double flowering plum (P. triloba ‘Multiplex’)

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is one of

the earliest bloomers and has come to symbolize the end of winter, lifting our spirits with its glorious outburst. Afterward, it is regarded merely as a shrub, but although its value is limited to this single performance, it’s worth a place in our landscape. Native to China and North Korea, it was introduced to Europe in 1855. The species name, triloba, means three-lobed and describes the leaves, while ‘Multiplex’ means much folded, a The double flowering plum (P. triloba ‘Multiplex’) with its glorious outburst of bloom, along with the prairie crocus, has come to signal spring.

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reference to the double flowers. An upright, spreading shrub of 1.8 to 2.7 m (6–9 ft) it has a profusion of double pink flowers in early spring. It does not fruit. CARE: Place in full sun or light shade on well-drained soil.

USE: Use in mixed or shrub borders or as an accent plant. If sensitively pruned, it can be utilized as a “see through” shrub, giving it particular appeal in and out of flower. Chokecherry (P. virginiana var. melanocarpa)

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is another

tough, dependable native shrub to use as a “pioneer species” when beginning a bare rural landscape. Chokecherry can thrive on neglect. A large, upright shrub or small tree native to much of temperate North America, many improved cultivars have been introduced in the last few decades. Up to 4.5 m (15 ft) in height and quite broad due to its tendency to sucker, it produces long racemes of fragrant white flowers in May, followed by clusters of small, black, edible cherries in July and August. They come into fruit by their third or fourth year. Although they are considered self-fruitful, cross-pollination improves yields (insects do the job). The dark green, shiny leaves are oval. The bark is smooth and grey. All of the introductions listed below are from the wild, selected for their superior fruiting or leaf colouration. When making a choice, consider size, form, ornamental value and fruit. ‘Bailey Select Schubert’ emerges with green foliage that changes to deep red in summer. It flowers and fruits profusely, reaching 5.5 m (18 ft) in height with a spread of 4.5 m (15 ft).

A tough dependable native tree, chokecherries (P. virginiana var. melanocarpa) do well where the going is tough.

‘Boughen’s Golden’ (Boughen’s Nursery, Valley River, Manitoba) has attractive yellow fruit of good flavour and little astringency that is good for syrup or white wine. It is similar to the species in size. ‘Garrington’ (Len Person, Bowden, Alberta) is multistemmed, reaching up to 3.7 m (12 ft) in height, with a pendulous form. The large, tart, black fruits are plentiful and found mostly on the exterior of the plant, which makes for easier picking. ‘Goertz’ (Alberta Tree Nursery and Horticulture Centre, Edmonton) has a columnar form up to 3.7 to 4.5 m (12–15 ft) in height and non-astringent, black fruit. ‘Lee Red’ (Lloyd Lee, Barrhead, Alberta) is a large plant, up to 4.5 m (15 ft) in height, with large, red fruit. ‘Midnight’ (Lakeshore Nursery, Saskatoon), 7.5 m (25 ft) in height with a 6 m (20 ft) spread, was selected for its dark purple foliage and lack of suckering.

Fragrant white flowers in May are followed by racemes of small black edible cherries suitable for jellies and wine.

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‘Robert’ (Lloyd Lee, Barrhead, Alberta), with a mature height of 3.7 m (12 ft), has large clusters of black fruit and deep purple summer foliage. ‘Schubert’ (Oscar Will Co., Bismarck, North Dakota) has a tree-like form up to 5.5 m (18 ft) in height, large purpleblack fruit and reddish-purple summer foliage. CARE: Hardy and drought tolerant, chokecherries are adapted

to a wide variety of soils and do well in full sun or partial shade. They are susceptible to black knot, a fungal disease, which can be partially controlled through pruning. USE: If pruned to a single trunk, chokecherries make an attrac-

tive small tree. On a small property, their tendency to sucker requires control (sometimes every spring). As a large shrub, they are useful in an informal shrub border, for wildlife plantings and in shelterbelts. The fruit makes an excellent jelly or (if it doesn’t set) syrup. They provide food and cover for birds.

Ussurian pear (Pyrus ussuriensis)

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The Ussurian pear is quite literally a “late bloomer,” taking up to The original purple-leafed chokecherry (P. virginiana var. melanocarpa), ‘Schubert’, was introduced many years ago from North Dakota.

a decade to come into flower, depending on its size when purchased. While not for those who require instant gratification, it’s well worth the wait. Pyrus is the Latin word for pear. The species name refers to the Ussuri River between Russia and China, to which it is native. Trees grown from seed by the famous British plant collector Ernest H. Wilson were introduced to Canada through Skinner’s Nursery of Manitoba via the Arnold Arboretum in 1918. The small (5.5 m/18 ft), low-headed tree has an oval form and branches covered with stout thorns. This is not a climbing tree! The foliage is thick, leathery and dark green. The fragrant, pure white flowers with contrasting black stamens are produced in early spring. The fruit is small and gritty and variable in quality. I once read that it made very good pear sauce, but in truth it is like sand with a fruity flavour. Still, the Ussurian pear is outstanding as an ornamental and serves as a pollinator for fruiting cultivars of pears such as ‘Early Gold’ and ‘John.’ ‘Bailfrost’ (‘Mountain Frost’) is similar to the species but more vigorous.

The Ussurian pear (Pyrus ussuriensis) is a small upright tree, well armed with stout thorns, with fragrant pure white flowers in early spring.

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‘Mordak’ (‘Prairie Gem’) is more compact and round. CARE: Grow on a range of soils in full sun.

USE: An attractive ornamental, especially in spring while in bloom, Ussurian pear should be used as a small specimen tree or in a mixed border.

Bur oak (Quercus macrocarpa)

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If ever I’ve loved a tree, it is bur oak. It has only once disappointed me: when I tried to grow it at the base of my septic mound, not realizing how truly saline the soil had become. In all other places, it has performed admirably. Quercus is the Latin name for oak, while marcrocarpa means large fruit and refers to the acorns. The “bur” of the common name, meaning a clinging seed case, is another reference to the fringed or “mossy cup” acorn. Native to Manitoba and southeastern Saskatchewan and

Bur oak (Quercus macrocarpa) is attractive, long-lived, with dark green, leathery foliage that turns yellow to brownish-red in fall.

east to the Maritimes, bur oak is large (15 m/50 ft or more), attractive and long-lived (about two hundred years). It has a straight trunk, a high head and branchlets with thick corky ridges. Although it has a long-standing (but undeserved) reputation for being “slow,” young trees on sandy soil have put on 30 cm (12 in.) of growth in a single season without supplemental water. Its leaves are typically oak-like, with seven to nine deep lobes, shiny green above and whitish below, with yellow to brownish-red fall colouration. It has a deep taproot. There are other oak species and cultivars that are also worthy of consideration. Northern pin oak (Quercus ellipsoidalis), native to northern Ontario, has leaves with distinctly pointed lobes, and given a protected site, should be hardy into zone 3 or perhaps even

Northern pin oak (Q. ellipsoidalis) is worth trying in protected locations.

colder areas. ‘Shooting Star’ is a fast growing selection of northern pin oak ideal for a moderate to expansive landscape. It was selected by Rick Durand (who spotted it while canoeing in northwestern Ontario) for its spectacular fall colour and because it was growing at the northern limits of the species. It is propagated by grafting it onto our native bur oak. Mongolian oak (Q. mongolica), native to Asia, is similar in appearance to bur oak and worthy of trial in the prairies. CARE: If not containerized (which most are nowadays), oak has

a taproot that makes it difficult to transplant once it is over 0.3 m (1 ft) high. Plant in full sun. Oaks are adapted to a wide range of soils from Winnipeg gumbo to sand.

‘Shooting Star’ is a fast growing selection of northern pin oak (Q. ellipsoidalis).

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USE: Oak is excellent as a shade or specimen tree in a medium to large lot. Because it has a taproot rather than a spreading, shallow root system, it does not compete with nearby lawns or flower beds.

Sumac (Rhus spp.)

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To many gardeners, sumac conjures up images of an autumn display of scarlet foliage and conical red fruit. The early onset of cold weather does not always allow this on the prairies. But its attractive compound foliage and its ability to cover ground in difficult circumstances are definite assets. They sucker readily, so chose their location with care. The genus name is from the classical Greek name for this plant, which describes the red fruit. ‘Gro-Low’ is a selection of the fragrant sumac (Rhus aromatSmooth sumac (Rhus glabra) suckers freely and soon forms a thicket. Its pinnately compound leaves have an almost tropical look to them.

ica) with dense, glossy foliage that turns red in the fall, red fruit and a height of only 0.6 m (2 ft). Native to Ontario and designated as hardy to zone 3, it is worthy of trial in the colder regions of the prairies. Smooth sumac (R. glabra) is a leggy, dioecious shrub of 1.8 to 2.7 m (6–9 ft) that suckers freely and soon forms a thicket. Glabra means smooth, a reference to the twigs, leaves and buds, which lack hairs or pubescence. Its large, pinnately compound leaves are dark green above and dull green below. The small, red-brown fruit is formed in dense, cone-shaped clusters and is often retained through winter. ‘Morden’ is less rambunctious in its suckering, with bright red fruit and a height of 1.8 m (6 ft). Western smooth sumac (R. glabra var. cis Montana) is similar and probably the toughest sumac for the colder regions of the prairies. Lemonade sumac or skunkbush (R. trilobata) is a low, spreading, native shrub of 1 m (3 ft). The leaves are aromatic when crushed and turn purple in the fall. The flowers, which appear before the leaves, are small, yellow and unpleasantly scented, hence skunkbush, the older common name. More recent marketing has changed the common name to lem-

Lemonade sumac (R. trilobata) was once called skunkbush due to the unpleasant smell of the small yellow flowers – until the marketers stepped in. The fruit clusters are red to orange.

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onade in an attempt to increase its saleability. The red to orange fruit clusters that follow are sticky and hairy. The species name, trilobata, means three-lobed and describes the leaves. ‘Autumn Amber’ is a low-growing (0.3–0.6 m/1–2 ft), non-

fruiting selection with foliage that turns yellow orange in fall. Staghorn sumac (R. typhina) has an antler-like branch structure with pubescent stems and a rather flat-topped form of up to 2.7 m (9 ft) in height. The fruit is cone-like and attractive, but it is not as hardy as R. trilobata. ‘Laciniata,’ a 2.5 m (8 ft) hybrid of R. typhina and R. glabra, has deeply cut, lobed leaflets. Designated zone 4, it is best placed in a sheltered location in the colder zones of the prairies. ‘Tiger Eye,’ a relatively new introduction of 1.8 m (6 ft), has outstanding yellow foliage but remains largely untested in the colder areas of the prairies. CARE: Plant on well-drained soils in full sun. They seem to tol-

erate pollution and do well on poor soils. Deer love them. USE: These large shrubs need space and are not suited to small yards or formal plantings. They are useful for massing, naturalization, reclamation, soil stabilization and wildlife plantings. Untested varieties with highly ornamental foliage could be treated as annuals and used as container plants.

Largely untested in the colder areas of the prairies, ‘Tiger Eyes’, a selection of staghorn sumac (R. typhina) has outstanding yellow foliage.

Currant and gooseberry (Ribes spp.) All of these shrubs produce yellow flowers followed by clusters of many seeded berries, many of which are edible. Their leaves are alternate and three-lobed. Some bear prickles or spines; others do not. The genus name, Ribes, is from the Persian or Arabic word for acid-tasting, a reference to the fruit. Alpine currant (Ribes alpinum) is probably most useful as a hedge in shaded areas. Its formal, stiff, upright appearance means it seldom if ever requires shearing. The species name, alpinum, means of the mountains, its native habitat in Europe, from Wales to Russia. An upright shrub of 1.2 m (4 ft), it has a tidy appearance due to its fine branches, density and fullness to the base. The small, bright green leaves appear very early in spring, turning a buff colour in fall. The inconspicuous yellow flowers are sometimes followed by red berries. It is dioecious, so plants of both sexes must be grown in close proximity to ensure fruit. Because they are often propagated from cuttings taken from a single plant (and therefore of the same sex), fruit is seldom produced.

An excellent hedge for shaded areas, alpine currant (Ribes alpinum) has a stiff upright appearance with little need for shearing.

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‘Green Mound’ is a disease-resistant, dwarf selection up to 1 m (3 ft) in height, suitable for low hedges or topiary. ‘Schmidt’ is said to be tougher and more vigorous than other alpine currants, adaptable to shearing and, with a height of 1.2 m (4 ft) and a spread of 1 m (3 ft), is excellent for low hedging. CARE: Alpine currants grow in a variety of soils in either sun

or shade. They appear more compact and dense in full sun. Spider mites are sometimes a problem, as is powdery mildew. Water well until established. They will benefit from a protected location in colder parts of the prairies. USE: Reputed to be fairly tolerant of urban air pollution,

alpine currants are used as an unclipped hedge, an informal grouping or massed as a ground cover or understorey beneath large canopy trees. If berries are present, they provide food for birds. Golden currant (R. aureum) Golden currant (R. aureum) is an excellent choice for tough, open rural areas.

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is another excellent large

species for tough, open rural areas. This shrub more or less looks after itself from the time it’s in diapers, so to speak. Place it where its suckering habit will be an asset rather than a liability. The species name, aureum, means golden and describes the golden-yellow flowers. A native plant found in the Cypress Hills and elsewhere on the prairies, it reaches 1.2 m (4 ft), with loose, open, arching branches, often becoming somewhat leggy with age. Like other currants, it lacks prickles. The fragrant, tubular, yellow flowers appear in late May and June and are followed by edible black currants. The tiny, light green leaves are three-lobed, wedge-shaped at their base and turn an attractive orange scarlet in the fall. It spreads through suckering. Missouri or clove currant (R. odoratum), native to South Dakota, is very similar to Ribes aureum, with wedgeshaped, three-lobed, bluish-green leaves. Up to 1.8 m (6 ft) in height with arching stems, it has yellow flowers with a clove-like fragrance, followed by edible black fruit. CARE: Golden currant is adapted to a variety of soils in sun or partial shade. Current worms often infest the fruit, causing premature drop. Powdery mildew is sometimes a problem.

The small three-lobed leaves of golden currant (R. aureum) turn an attractive orange scarlet in fall.

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USE: Plant it where you can take advantage of its fragrance. Its form makes it unsuitable for formal plantings and its tendency to sucker limits it to larger lots, acreages and farmyards. It is

also used as a wildlife planting, providing food and cover for birds. It is a butterfly nectar plant. The edible fruit is used for jams and jellies. Canadian gooseberry (R. lacustre, syn. R. oxyacanthoides

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var. lacustre) is a low, spreading native shrub. I planted it a little ways back from my perennial border, somewhat hesitantly because I feared it would sucker uncontrollably. In the decade that it has been there, it has expanded only slowly, has proven quite controllable (if not huggable) and has elicited questions as to its identity from many visitors. The species name comes from the Greek: oxys means sharp and akanthos means thorn, a reference to the sharp, slender prickles, which are held on thin, wiry stems up to 1 m (3 ft) in height. The light green, lobed leaves turn yellow orange in fall. The flowers are an inconspicuous yellow green. The edible berries are reddish-purple when ripe. ‘Dwarf Dakota’ is a compact selection with a spreading form and exceptionally glossy foliage that turns red

Canadian gooseberry (R. lacustre), a low spreading native shrub, produces edible reddishpurple berries.

bronze in fall. CARE: Resistant to mildew, wild gooseberry may be planted in

full sun or partial shade on well-drained soil. USE: Wild gooseberry is used for massing, wildlife plantings and

underplantings. Its sharp thorns make it a good barrier planting.

Rose (Rosa spp.) While most hybrid tea roses would die a quick death in the prairie xeriscape, many of their tougher cousins, the shrub roses long grown on the prairies, are attractive, hardy and drought tolerant. Most are large and prickly and some sucker, but many are long-flowering and most are long-lived. Among these shrub roses are native and introduced species as well as hybrids developed by prairie plant breeders. There are several species of native roses. Prickly rose (Rosa acicularis)

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is up to 2.5 m (8 ft) in

height. The species name, acicularis, means sharp-pointed and refers to the abundant prickles on younger stems. The rosy-pink, highly fragrant flowers occur singly in June and July and are followed by red, long-necked, pear-shaped hips which persist over winter. Prairie rose (R. arkansana)

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was used in much of the

hybridizing work that produced the Parkland series of roses.

The wild or woods rose (Rosa woodsii) is up to 1.5 m (5 ft) with pink flowers in small clusters.

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Flat, pink flowers bloom from June to August. Short (up to 0.6 m/2 ft) and bushy, it may die back to ground level each winter but blooms reliably on the current season’s wood. Wild rose or woods rose (R. woodsii) is up to 1.5 m (5 ft) in height, with pink flowers produced in small clusters, followed by round, red hips. Both the common and species name refer to its habitat, the woods. Many of the more drought-tolerant roses have R. rugosa or R. spinosissima parentage. Among the most drought-tolerant non-native species and hybrid varieties are: Altai rose (R. spinosissima, syn. R. pimpinellifolia)

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from Asia, is an upright, somewhat leggy plant of 1.5 to 1.8 m (5–6 ft). The large, slightly fragrant, single, creamywhite flowers appear in early June, followed by very large, purple-black hips. It suckers freely and is good for screening or an informal shrub border. The ‘Yellow The Altai rose (R. spinosissima) has large single creamy flowers that are followed by large, purple-black hips.

Altai,’ a hybrid developed by Percy Wright, is similar but with bright yellow, single flowers. ‘Hansa’ is a rugosa hybrid with large, highly fragrant, red-purple, double flowers with repeat bloom. The shrub is large (1.8 m/6 ft) and round, with the characteristic handsome, wrinkled, dark green leaves of the rugosa rose (rugosa means wrinkled). ‘Hazeldean’,

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a hybrid of Percy Wright, is so startlingly

beautiful when in full bloom it could cause accidents if planted near a highway. It is a double yellow rose that flowers in June and is resistant to black spot. About 1.5 m (5 ft) in height, it suckers freely. ‘Marie Bugnet,’ developed by George Bugnet of Alberta, is smaller than most and non-suckering and therefore excellent for a smaller landscape. It is 0.6 to 1 m (2–3 ft) in height with fragrant, white flowers throughout the summer. ‘Prairie Youth,’ an early Morden introduction, is a little over 1.8 m (6 ft) in height, with arching branches and clusters of salmon pink flowers from June to fall. ‘Therese Bugnet,’ another George Bugnet introduction, is a tall rose, 1.8 m (6 ft) in height with a spread of 1.5 m (5 ft). It has large, deep pink, very fragrant, double flow‘Hazeldean’, a hybrid rose of Percy Wright’s, has hundreds of double yellow flowers in June and is resistant to black spot.

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ers. A rugosa hybrid, it has recurrent bloom and does not sucker. The red stems are almost prickle-free.

Red-leafed rose (R. glauca, syn. R. rubrifolia)

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is an

upright, 1.8 m (6 ft) shrub rose with arching branches and reddish-purple stems and leaves. The flowers are single and pink and the dark orange, oblong hips are retained through winter. CARE: These roses grow best in full sun in soil enriched with

organic matter. They’ll perform better with mulching, protection from wind and even moisture during establishment. Once established, they are drought tolerant. USE: Shrubs roses are used as ornamentals, for naturalization,

reclamation, in shelterbelts and in wildlife plantings, where they provide food and excellent nesting cover for birds and serve as butterfly nectar plants. The larger shrub roses and those that sucker are suitable for an informal (untrimmed) hedge or an informal shrub border. Shorter, non-suckering types can be planted in smaller urban yards where other roses might be used, where they work well in a mixed border. Their hips provide fall and winter landscape value and are used in jelly.

European red elder (Sambucus racemosa)

Noted for its reddish-purple stems and leaves, the red-leafed rose (R. glauca) has single pink flowers. Dark orange, oblong hips are retained through winter.

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These large, lush shrubs have an almost tropical appearance, with their red fruit and large compound leaves, but are thoroughly at home on the Canadian prairies. They often show up in unexpected places, having earned Air Miles as they make their way through the digestive tracts of birds. Sambucus was the Roman name for this shrub, possibly from sambuca, a harp made of elder wood. The species name, racemosa, meaning “in racemes,” refers to the flowers. Native from Europe to Western Asia, elders are tall, loose shrubs with arching branches, 1.8 to 2.7 m (6–9 ft) in height. Creamy flowers in flat terminal clusters are followed by dense clusters of small, scarlet berries. They have finely divided, pinnately compound leaves, each with three to seven coarse-toothed, dark green leaflets. Fast-growing, red elders are capable of putting on 0.6 to 1 m (2–3 ft) of growth per season, producing stout but pithy stems. Unfortunately, they may occasionally suffer the same degree of dieback, which usually shows up the following spring. Golden-leafed cultivars and dwarf forms are available. Larger types may be pruned to a single trunk to form a small tree. Selections of black elder (S. nigra) are less hardy, not drought tolerant and are better used as “annuals” in zone 2: put in a large container for the season and left to die over winter. Black elders will seldom overwinter in zone 2 and colder.

‘Sutherland’ cutleaf elder (Sambucus racemosa), introduced by Les Kerr, is a vigorous plant of 1.8 m (6 ft) or more with golden foliage.

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‘Dropmore Fernleaf,’ introduced by Frank Skinner of Manitoba, is exceptionally hardy, vigorous and drought tolerant and should be much more widely planted and commercially available. It is 1.8 m (6 ft) or more in height, with finely divided green foliage that has a hint of purple in both spring and fall. ‘Golden Glow,’ a recent release from the Morden Research Station, is 1.5 m (5 ft) in height, with bright yellow spring foliage becoming yellow green in summer. ‘Goldenlocks,’ an introduction of Les Kerr, is only 1.2 m (4 ft) high, with finely divided golden foliage throughout the summer. With sensitive pruning, it is an excellent specimen plant for a Japanese-style garden. Golden elder (S. racemosa ‘Aurea’) is larger, with a height of 2.7 m (9 ft) and golden-yellow foliage. Golden elder (S. racemosa ‘Aurea’) is 2.7 m (9 ft) with golden yellow foliage. For contrast, plant it adjacent to a shrub with purple foliage.

‘Sutherland Golden,’ also introduced by Les Kerr, is a vigorous plant with a height of 1.8 m (6 ft) or more and golden foliage. CARE: Elders grow in a range of soils in full sun or partial shade,

but will bloom and fruit less in shade. All golden-leafed types require full sun to develop golden colouration. When dieback occurs, there may be some maintenance in pruning the dead wood in spring, but vigorous new growth generally occurs. USE: As shrubs, they are best used in informal plantings or for naturalizing, screening and wildlife plantings. As a small tree, elders are well placed in a smaller urban setting. They provide food and cover for birds and are a butterfly nectar plant. Birds are an active agent of propagation.

Silver buffaloberry (Shepherdia argentea)

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A large shrub with a tendency to sucker, the silver foliage and bright fruit, combined with both salt and drought tolerance, make it an ideal candidate for highway plantings and reclamation. The genus was named to honour John Shepherd (1764-1836), curator of the Liverpool Botanic Garden. The species name, argentea, meaning silver, describes the leaves and stems. The fruit was used by Indigenous peoples to flavour buffalo meat, hence the common name. A large native shrub with a tendency to sucker, buffalo berry (Shepherdia argentea) soon forms dense thickets. It’s widely used for highway and shelterbelt plantings.

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Buffaloberry is a large native shrub up to 3.7 m (12 ft) in height that often forms dense thickets through suckering. Branchlets grow almost perpendicular to the main stems (giving it a “telephone pole” effect) and terminate as stout thorns. The

simple leaves are oval to elliptical. The creamy-white, inconspicuous flowers bloom in May and are followed by clusters of red – or sometimes orange or yellow – berries in midsummer. Because it is dioecious, plants of both sexes must be in close proximity to ensure fruit. Russet buffaloberry (Shepherdia canadensis), only 1 m (3 ft) in height and round and upright in form, is also native to the prairies. It has grey green leaves with a brown underside. The yellow flowers are followed by red to orange fruit. CARE: Buffaloberries grow on any well-drained soil in full sun

to partial shade and are saline tolerant. USE: Because of its size and tendency to sucker, silver buffa-

loberry is best used as an informal planting on a larger lot, for screening or as a barrier planting. It is used extensively for reclamation as well as wildlife, highway and shelterbelt plantings, where it provides food and cover for birds. It may be pruned to a single stem and used as a small specimen tree in a smaller space, although sucker removal will be required. Russet buffaloberry may be used for informal plantings, an understorey and naturalization.

Ural false spirea (Sorbaria sorbifolia)

‘Aurora’, a hybrid false spirea (Sorbaria), suckers less than the species and has a whiter cleaner look to its blooms.

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If you’ve never encountered the cultivars ‘Aurora’ or ‘Sem,’ your impression of the Ural false spirea just past full bloom may be that of a large rambling shrub covered in browning Kleenex, its only virtue being its ability to grow in shade. ‘Aurora,’ introduced almost seventy years ago, is quite different and it should be much more readily available. The genus name, Sorbaria, refers to its resemblance to Sorbus (mountain ash), as does the species name, sorbifolia, which means with leaves like mountain ash. Native to Asia, the false spirea is a tough, hardy shrub with a very fine texture. The arching stems carry large, pinnately compound leaves, each with 13 to 23 leaflets. The foliage emerges early. Large, soft panicles of creamy-white flowers, which somewhat resemble spirea, are produced in late July on the current season’s wood and are highly attractive to bees. It is 1 to 1.8 m (3–6 ft) in height, upright and spreading, tends to sucker and can soon form a thicket. ‘Aurora,’ a hybrid of S. sorbifolia and S. arborea, was introduced by Frank Skinner of Manitoba in 1941. It suckers less than the species and has a much “whiter” look as the flowers are sterile and drop off cleanly after bloom, avoiding the “browned Kleenex” stage.

‘Sem’ false spirea (Sorbaria sorbifolia) is an amazing ground cover for a dry shaded area. Its foliage is pink-red in spring, becoming chartreuse in summer.

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‘Sem’ is shorter (1.2 m/4 ft) and more compact, with extremely attractive pink-red spring foliage, becoming chartreuse in summer. CARE: False spirea is highly adaptable, tolerating neglect, a

wide range of soils, drought, full sun or shade. It is occasionally susceptible to spider mites. USE: Because of its tendency to sucker, it is little used in formal plantings or smaller urban lots. It is better placed in a more wild or naturalized setting or used for reclamation, highways or to stabilize a slope or bank. With its interesting foliage, ‘Sem’ can be used as an annual in containers (to avoid suckering) on smaller lots and is an excellent ground cover in shaded areas next to garages or along back lanes.

Showy mountain ash (Sorbus decora) Native to Manitoba, this is the hardiest and most disease-resisShowy mountain ash (Sorbus decora), native to Manitoba, is the hardiest and most disease resistant of the mountain ashes grown on the prairies.

tant of the several mountain ashes that are grown on the prairies. It is also the most drought tolerant. Add to this outstanding four season landscape value and a size that’s compatible with a small urban yard and you end up with a winner. A tree long associated with magic, Sorbus means stop, possibly a reference to warding off witchcraft. The species name, decora, means decorated or showy. The common name describes the similarity of its foliage to that of the ash. Oval to rounded in form and about 7.5 m (25 ft) in height, it has greyish, paper-like bark. Flat clusters of showy white flowers appear in spring, followed by orange red fruit that persists through winter, offering a sharp contrast to an otherwise white landscape (until consumed by flocks of waxwings). The bluishgreen, pinnately compound leaves turn a brilliant red in fall. CARE: Plant in full sun on well-drained soil and water well until

established. USE: The showy mountain ash is excellent as a shade tree in a

small to medium yard or grouped as part of a tree-shrub border in a larger landscape.

Three-lobed spirea (Spiraea trilobata) Three-lobed spirea is one of those rare beauties that gives so much The bright red fruit of showy mountain ash (S. decora) is retained through winter until consumed by waxwings.

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for so little effort on the part of the gardener: a profusion of white flowers and a willingness to produce them in full sun or partial shade. One of the best white spireas, with a dense, neat appearance and foliage retained to its base, it should be planted more often.

The genus name is derived from the Greek word speiraira, meaning a plant used for garlands, something of which the Greeks were fond. Trilobata means three-lobed, alluding to the small, blue green leaves. Native to Asia and up to 1.2 m (4 ft) in height, three-lobed spirea has arching branches covered with a profusion of single, white flowers in late May. ‘Fairy Queen’ (S. trilobata x S. trichocarpa), a Frank Skinner introduction that reaches up to 1.5 m (5 ft) in height, flowers profusely with dark green foliage. ‘Summer Snow,’ with a height and spread of 60 by 70 cm (24 x 28 in.), has light green foliage and masses of white flowers from June to September. CARE: Plant in full sun or partial shade on a range of well-

drained soils. USE: Spireas may be used as foundation plantings or in a

mixed or shrub border.

Western snowberry (Symphoricarpos occidentalis)

‘Summer Snow’ is a dwarf selection of three-lobed spirea (Spiraea trilobata) that blooms most of the summer.

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A tough, smaller shrub with a great propensity to travel, its use is generally limited to reclamation, naturalization and highway plantings. That said, Dieter Martin used it very effectively as an understorey below large shade trees on the University of Saskatchewan campus. The genus name, symphoricarpos, means “fruit borne together” and refers to the dense clusters of waxy, greenish-white berries. The berries, toxic if eaten in large quantities, are retained through winter, but change colour to a purplish light brown. The species name, occidentalis, means of the west and reflects the common name. A member of the honeysuckle family, snowberry is a native shrub, 0.6 to 1 m (2–3 ft) in height, which forms dense clumps or thickets and suckers readily. The inconspicuous, pink-andwhite flowers are borne in late June and early July. The small, oval leaves are grey green and opposite. Stems are hollow. Common snowberry (Symphoricarpos albus), also native to the prairies, is similar but somewhat larger. It has larger, bright white berries. It does better in deeper shade. CARE: Grow in full sun to partial shade on well-drained soil. USE: Snowberry can be massed as a ground cover, used as

an understorey below trees and for naturalization, reclamation and highway plantings. It provides food and cover for birds

Western snowberry (Symphoricarpos occidentalis) is a small, tough native shrub that suckers readily to form a ground cover in sun or shade.

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and is a hummingbird nectar plant. It suckers too profusely for small or formal landscape use.

Lilac (Syringa spp.)

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If space allows, plant many lilacs. If space is limited, select three or four of the smaller varieties. If really limited and you’re reduced to a single lilac, plant a Meyer lilac and prune it to a three-trunked small tree form. The genus name, Syringa, is from the Greek syrinx, a pipe and describes the hollow stems. One of the most frequently planted shrubs on the prairies during the early part of the twentieth century, lilacs are vigorous shrubs, usually 1.8 to 3.7 m (6–12 ft) in height. They are grown primarily for their large, fragrant panicles of white, pink, lilac, blue or purple flowers, which may be single or double. Except for the Japanese tree lilac, their landscape value is not outstanding when not in bloom, but who can forego the sweet scent of lilacs? The following species and their hybrids are recommended. ‘Maiden’s Blush’ hyacinthflowered lilac (Syringa x hyacinthiflora) is upright, spreading and about 2.7 m (9 ft) in height.

There are many more. Hyacinth-flowered lilacs (Syringa x hyacinthiflora) are about 2.7 m (9 ft) in height, upright and spreading. They are hybrids of S. vulgaris and S. oblata var. dilitata, developed mostly by Frank Skinner of Dropmore, Manitoba. Their flowers are large, showy and fragrant. They vary in the degree to which they sucker, but generally less than the common lilac (S. vulgaris). Among these cultivars are: ‘Assessippi’ (single, purple), ‘Maiden’s Blush’ (single, pink), ‘Pocahontas’ (single, reddishpurple), ‘Royal Purple’ (double, purple blue), ‘Sister Justina’ (pure white, fragrant, double, little or no suckering) and ‘Mount Baker’ (single, white). Meyer lilac (S. meyeri) is a compact, dwarf shrub of 1.8 m (6 ft) with small, glossy leaves. Gently rounded, it produces an abundance of attractive, fragrant, small, pink to purple flowers in small clusters in late June. It begins blooming at a very young, almost unseemly age. I have seen plants of only 30 cm (12 in.) in full flower. It suckers only a little. Introduced from northern China in 1908, it should be much more widely used and would be the lilac of choice for smaller yards. To prune it to a miniature tree form, select three to five equidistant, graceful branches as trunks, removing extraneous growth to

‘Miss Canada’ lilac (Syringa x prestoniae), about 2.7 m (9 ft) in height, is a beauty! Large racemes of deep pink flowers emerge from almost red buds.

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about 1 m (3 ft) above ground level. Preston lilacs (S. x prestoniae), hybrids of S. villosa and S. reflexa, were developed for the most part by Isabella

Preston of the Central Experimental Farm in Ottawa in the early 1900s. They are fragrant, late blooming and tend to be non-suckering. Sturdy, dense and upright, they are about 2.7 m (9 ft) in height, with a coarse texture and large leaves. Among this group of hybrids are: ‘Coral’ (compact, with clear true pink flowers), ‘Donald Wyman’ (dense, redpurple, single flowers with attractive, small, dark green leaves, a Skinner introduction from Manitoba), ‘James MacFarland’ (single, clear deep pink flowers in dense clusters), ‘Minuet’ (dense, dark, shiny foliage and light purple buds that open to pale pink) and ‘Miss Canada’ (clear, deep pink flowers emerging from almost red buds, in large racemes). Japanese tree lilac (S. reticulata) is the tallest of the lilacs, up to 8 m (26 ft). It blooms in late June or early July, with large, cream-coloured flowers in loose, triangular-shaped racemes. A handsome tree, it is generally pruned to a single trunk. It should be planted more often. ‘Golden Eclipse’ is a recent introduction with creamy variegated foliage throughout the growing season, but it is only hardy to zone 3a. Gardeners in colder parts of the prairies should plant it in their most protected location. ‘Ivory Silk’ is an improved selection with attractive, brown-patterned bark and blue green, leathery leaves. Late lilac (S. villosa) is 2.7 m (9 ft) in height and has pale pink to rosy lilac flowers, usually small and sparsely produced.

‘Ivory Silk’ is a cultivar of the Japanese tree lilac (S. reticulata), 8 m (26 ft) in height, blooming in late June.

The species name, villosa, means covered with hairs and refers to the leaves, which are large, coarse and dull. It is non-suckering. Native to northern China, villosa lilacs form part of shelterbelts throughout the prairies. Common lilac (S. vulgaris) originally from southeastern Europe, is a large (3.7–4.5 m/12–15 ft), dense and vigorous shrub, upright and spreading, with a very strong suckering habit. Its fragrant flowers are freely produced. A tough shrub the

for French

difficult hybrids

situations, originally

it

is

a

parent

developed

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to the

Lemoine Nursery in France. Among the hybrids are: ‘Beauty

of

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(double,

light

pink),

‘Charles

Joly’ (large, double, heavily scented, magenta panicles), ‘Congo’ (single, magenta flowers in large dense panicles), ‘Ludwig Spaeth’ (abundant single, deep red purple blooms), ‘President Lincoln’ (heavy clusters of single, Wedgwood blue panicles) and ‘Sensation’ (single purple, each petal edged in white).

The late or villosa lilac (S. villosa) has formed shelterbelts across the prairies since the beginning of settlement.

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Smaller lilacs, suitable for smaller landscapes, are also available. The following are all hardy to zone 3. In colder regions of the prairies, place them in sheltered locations. ‘Josee,’ a complex hybrid of S. patula x S. macrophylla and the Meyer lilac, is up to 1.2 m (4 ft), with fragrant, single, pink flowers. ‘Little Boy Blue,’ selected by Father John Fiala, a parish priest from Ohio who spent a lifetime breeding lilacs, is 1 to 1.2 m (3–4 ft), with single, blue flowers. ‘Miss Kim’ (S. patula ‘Miss Kim’) is a compact, 1 to 1.8 m (3–6 ft) shrub, native to Korea and northern China, with dark green foliage to its base. The foliage sometimes turns reddish-purple in fall. It produces small but abundant clusters of fragrant, pale lavender flowers. It is ideal for shrub borders, mixed borders and foundation plantings. ‘Sensation’, a recent introduction of the common lilac (S. vulgaris) has proved both extremely drought tolerant and hardy.

‘Sugar Plum Fairy,’ is 1.2 m (4 ft) in height, with single, rose flowers. ‘Tinkerbell,’ grows to 1.5 m (5 ft) and has single, deep pink flowers. CARE: Lilacs grow in a wide range of soils in full sun. They do

not tolerate flooding or poor drainage. Allow two to three years for establishment. Until they reach maturity, they may not achieve their true colour and form. USE: Larger lilacs are ideal for screening, shelterbelts and infor-

mal shrub borders in larger yards. Japanese tree lilacs make excellent small shade trees. As a formal sheared hedge, lilacs have little to offer – the very process of shearing substantially reduces their flowering capacity for the next season. Smaller lilacs are useful in a mixed border. Lilacs are a nectar source for bees and butterflies. Stems brought indoors in February may be forced for winter bloom. Seeds provide food for birds through the winter.

American basswood (Tilia americana) The drought tolerance of some trees comes as a surprise. I’d always read that American basswood liked a deep, moist soil, but then realized I had one growing in sandy soil where it hadn’t ‘Miss Kim’ (S. patula) is among the smaller lilacs. Hardy to zone 3, place in a protected location in colder regions of the prairies.

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been watered for well over a decade and it was doing just fine. Perhaps, like many, it fits into the category of drought tolerant “once established.” Native to southeastern Manitoba, it has a dense, rounded

crown, a height of about 15 m (50 ft) and a deep root system. The bark is grey-brown and the large, dark green leaves are heart-shaped and serrated. Small, creamy-yellow, exceptionally fragrant flowers are subtended below bracts. They appear in midsummer and are followed by nutlets that are retained over winter. CARE: Plant in full sun in a range of soils. Moderately fast

growing, it performs better with even moisture, but is quite drought tolerant once established. USE: The American basswood makes an excellent shade or boulevard tree. Plant it where you can take advantage of its sweet fragrance.

Wayfaring tree and nannyberry (Viburnum spp.)

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The genus name is derived from the Latin word viburna, once used to describe shrubs with flexible branches used for tying or binding. Both the wayfaring tree and nannyberry are considered large shrubs or, if pruned to a single trunk, small trees. They boast extended landscape value with spring flowers as well as attractive fruit and foliage. Wayfaring tree (Viburnum lantana) is one I never really warmed to until I was smitten by the variegated form in nurseries in Ontario and British Columbia. Convinced that this was yet another romance with a foreign beauty that

Native to southern Manitoba, the American basswood (Tilia americana) is a large tree with small, creamy yellow, wonderfully fragrant flowers.

would end in death by the following spring, I nevertheless purchased and planted them. They survived their first two prairie winters without snow cover and have continued to flourish. In the interim, I’ve begun to sense both a quiet beauty and a workhorse in the species. Plant both the species and its variegated form. You won’t be disappointed. In the late 1500s, English herbalist John Gerard called it the wayfaring tree because it brought joy to travellers. It was once planted near cowsheds to ward off witchcraft. Native to Europe and western Asia, this is generally a large, spreading shrub, 2.7 to 3.7 m (9–12 ft) in height with a spread of 2.7 m (9 ft), but is occasionally seen pruned to a small tree. The soft grey green leaves have a matt-like, wrinkled texture with little fall colour. Flat, white flowers clusters are followed by fruit that turns from yellow to red to purple black. ‘Variegatum,’ with soft, creamy-yellow and grey green variegated foliage, is as hardy and drought tolerant as the species and should be much more widely available to prairie gardeners.

The variegated wayfaring tree (Viburnum lantana ‘Variegatum’) is exceptionally drought tolerant and perfectly hardy.

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CARE: Plant in full sun or partial shade on a range of soils. It has

a neater appearance in full sun. USE: The wayfaring tree may be used as a small specimen tree

or in a mixed tree-shrub border. It is ideal for a smaller lot or as a grouping in a larger landscape. Nannyberry (V. lentago) has exceptional fall colour. Its only drawback is a mild tendency to sucker. This characteristic is variable from plant to plant, but trying to fight it through pruning off the offending suckers is akin to cleaning the Aegean Stables: You will never win. Better to plant it where it can have its way. On the plus side, it is extremely attractive, has excellent three-season landscape value and is sadly underused. The species name, lentago, means flexible or supple and is The fruit of the wayfaring tree (V. lantana), formed in clusters, turns from yellow to red to purple black and is very attractive.

from the Latin word lentas. This reference is presumably to the stems. Native to Manitoba, nannyberry is a small tree of 6 to 9 m (20–30 ft), with lustrous, oval, finely toothed leaves that turn a glorious red in fall. The creamy-white flowers are produced in round clusters in May and June and are followed by berries that turn from green to yellow to red to blue. Often all colours are present at once in a single cluster. CARE: Plant in full sun or partial shade on a range of soils, as

long as they are well drained. It is best mulched as it suckers more if the roots are damaged or disturbed by tilling. USE: Ideal in a small landscape or grouped in a larger landscape, it can be multi-trunked or pruned to a single trunk. Place it in an informal tree-shrub border. The fruit is consumed by birds.

“While there are more drought-tolerant perennials available to prairie gardeners than ever before, some of the older perennials, of great garden worth and Nannyberry (V. lentago) has round clusters of creamywhite flowers in May and June followed by berries that turn from green to yellow and then red to blue. Its fall foliage is an intense orange red.

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dependability, are becoming increasingly difficult to find.”

CHAPTER 8

Perennials

There are more drought-tolerant perennials available to prairie gardeners than ever before – new genera, new species and new cultivars. Who had heard of Russian sage, giant fleeceflower, spring adonis or culver’s root in the mid-1990s? On the opposite side of the coin, some of the older perennials, of great garden worth and dependability, are becoming increasingly difficult to find. And many of the newer introductions are largely untested in terms of hardiness on the prairies. That job generally lies with the consumer. If you’re unsure of a perennial’s drought tolerance or hardiness, ask at a nursery, a Master Gardener, go on a local garden tour or join a garden club or horticultural society. The beauty of these plants, coupled with their (hopefully) perennial character and unique characteristics, makes them very worthwhile.

Yarrow, achillea (Achillea spp.)

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Yarrow (Achillea millefolium) is a circumpolar species that has been in cultivation for many centuries. It has come a long way since the days when ‘Cerise Queen’ was considered the standard. If you were disappointed with its floppiness, invasive habit and lacklustre colour, get ready to embrace the more recent introductions. They’re more upright and clumplike, are less likely to overrun your borders and come in striking colours. Yarrow has flat flower heads in mid to late summer atop ferny, finely cut, aromatic, dark green foliage. Plants range from

Peonies with single or anemone type flowers have a charm all their own. And they’re much less likely to bend over in the mud when it rains.

30 to 90 cm (12–36 in.) in height. Named for the Greek hero Achilles, who is said to have used Achillea to heal his soldiers’ wounds, the species name, millefolium, means a thousand leaves and refers to the fine foliage.

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‘Anthea’ is 60 cm (24 in.) in height and spread, with soft yellow, 8 to 12 cm (3–5 in.) flower heads. ‘Apricot Delight’ is a newer, largely untested variety that is worthy of trial, with a compact form, 30 cm (12 in.) in height and spread and pale apricot to near red flowers. ‘Credo’ is a creamy lemon-yellow of 75 to 90 cm (30–36 in.). ‘Fire King’ is a deep carmine red, 60 cm (24 in.) in height. ‘Paprika,’ part of the Galaxy series, is the same height but has yellow-centred flowers, blooming midsummer to fall, of the same rich colour as the spice, atop dark green foliage. ‘Summer Berries,’ a new introduction largely untested on the ‘Paprika’ is a recent yarrow (A. millifolium) introduction that is more clump-like and less invasive than the older types.

prairies but worthy of trial, resembles ‘Summer Pastels’ but with a blend of deeper, brighter, non-fading colours. ‘Summer Pastels,’ an All-America Selections winner, is 60 cm (24 in.) in height with flowers in pink, rose, apricot, cream, red, beige, purple or white. ‘Terracotta’ is the colour of a terracotta clay pot and is 75 to 90 cm (30–36 in.) in height. CARE: Grow in full sun on well-drained soils. Older varieties spread readily by rhizomes and will need control (with a sharp spade!) within a border. Divide every three to four years. Deadhead for a neater appearance and more continuous bloom. USE: This long-flowering perennial can be used massed, as a tall ground cover, for naturalizing, in the perennial border and in fresh and dried arrangements. It is a nectar plant for butterflies. Sneezewort (A. ptarmica) is an excellent but slightly shorter substitute for the mostly banned baby’s breath (Gypsophila paniculata). Sneezewort has graced our gardens for centuries. Its roots and leaves were once used as a cheap replacement for snuff (ptarmica is the Greek word for sneezing), thus the common name. Native to Europe and Asia and naturalized in North America, sneezewort is covered with hundreds of tiny, double, pure white flowers in July and August on 45 to 60 cm (18–24 in.) stems. The foliage is fern-like and somewhat pungent.

An old fashioned perennial with white, button-like flowers, sneezewort (A. ptarmica) was once used as snuff.

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‘Angel’s Breath’ has large, double, white flowers and is 50 cm (20 in.) in height. ‘Perry’s White’ is a double white, 60 cm (24 in.) in height.

‘The Pearl’ is very similar to ‘Perry’s White’. CARE: Plant in full sun on poorer, well-drained soils. In richer

soils it is invasive. Divide every three to four years. It may occasionally get powdery mildew. USE: Sneezewort is useful in informal borders and for natural-

izing, as well as in fresh and dried flower arrangements. Dwarf woolly yarrow (A. tomentosa) is an ideal plant for hot, dry areas where the going is tough. Tomentosa means hairy or woolly and like the common name refers to the foliage, which is aromatic, finely cut and a soft woolly grey. The flowers are yellow and produced in flat clusters just above the foliage in June. A low (15–20 cm/6–8 in.) ground cover, its leaves form a dense mat. A. tomentosa var. Aurea has more intensely golden flowers.

Dwarf woolly yarrow (Achillea tomentosa) is ideal as a ground cover or in a rock garden.

CARE: Plant in full sun in well-drained soil on a hot, dry site. USE: Woolly yarrow is excellent as a ground cover, edging, for

interplanting among paving stones towards the edges of a walk or patio or in a rock garden. It is easily mowed for a neater appearance or rejuvenation in midsummer after flowering.

Spring adonis (Adonis vernalis) My first experience growing spring adonis was from seed. I sowed all ten seeds from the packet outdoors in a cold frame in the fall. The following spring, two germinated. A lazy gardener, I left both the tiny seedlings and the remainder of the ungerminated seeds where they were, which proved to be more good luck than good management. The seedlings grew strong enough to transplant the following spring, when the remaining eight seeds germinated. I later read that it often takes two winters before germination occurs. They have since proved to be exceptional perennials – lovely to behold in early spring with their buttercup-like flowers, long-lived, perfectly hardy and almost no maintenance. I’ve seen them growing with utter abandon in a public garden cared for by the local horticultural society in Dawson Creek. I had planted mine in shade and ensured they had even moisture, but these were growing in full sun with little or no supplemental water. Unfortunately, they are not easy to obtain, either as plants or seed and may take a bit of work sourcing. They are indeed worth the effort, however, and should be much more widely available. The genus is named for the Greek god Adonis, well known

Spring adonis (Adonis vernalis) is hardy, lovely, long lived and drought-tolerant, but often difficult to source. Nag your local supplier.

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for his good looks, who was changed into this flower after being killed by a wild boar. Vernalis means of spring, when they flower. They are native to southeast and central Europe through to Siberia. The small plants form clumps 20 to 30 cm (8–12 in.) in height. The golden, buttercup-like flowers are held on unbranched stems. The foliage is finely divided with a fine, ferny appearance. CARE: Plant in sun or shade on a variety of soils. Good drainage is preferred. Once established, they do not transplant well (although they will self-seed), so choose your location carefully. USE: Use them in rock gardens or at the front of the border.

Goutweed, bishop’s goutweed (Aegopodium podagraria var. variegatum) This is the first perennial you’re taught to hate when you join a Spring adonis (Adonis vernalis) blooms early and does well in sun or shade.

garden club or horticultural society. If it can be contained, however, by cement walks or other impervious barriers, it is very useful as a ground cover on shady slopes or other inhospitable sites. It’s far too invasive for a border and you will deeply regret placing it there. The species name is from the Latin podagricus and means used in treating gout or arthritis, presumably an occupational hazard of bishops of the time, perhaps for reasons of diet and lack of exercise. Native to Europe, it is deep-rooted and persistent. Although it wilts during periods of heat and drought, it recoups immediately with the onset of cooler temperatures and moisture. Its compound leaves with variegated white margins remain attractive throughout the growing season. Small white flowers are produced in midsummer in umbels above the dense foliage, which is 30 to 38 cm (12–15 in.) in height. On drier sites it may be shorter. CARE: Goutweed will grow anywhere but is best planted in

poor soil in full sun or partial shade. It is extremely aggressive and will overpower less vigorous neighbours. Remove any shoots that revert to green. It may brown in dry sun. Mow if it appears untidy.

Goutweed (Aegopodium podagraria var. variegatum) is useful as a ground cover, but place it carefully – where it can be contained between a rock and a hard place.

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USE: Goutweed is excellent as a ground cover where it can be contained (between a driveway and a sidewalk), where nothing else will grow (such as under a deck), as an understorey below large trees or to hold a slope. It will certainly brighten a shady corner. Do not use it in a border or rock garden.

Giant hyssop (Agastache foeniculum) Native to the prairies, giant hyssop is a member of the mint family, which is characterized by square stems and opposite leaves. Of the many hyssops available to the gardening public in recent decades, this is one of the few that is hardy on the prairies, albeit sometimes short-lived. Others are “treated as annuals” with high hopes that they will perpetuate themselves through reseeding. Sometimes called the anise hyssop, its medium green, oval leaves are anise-scented and have been the basis of a tea. Numerous spikes have whorls of two-lipped blue flowers with bracts tinged with violet, somewhat resembling a bottle brush (similar to Stachys lanata). The flowers are produced on 1 to 1.2 m (3–4 ft) plants from July to September. ‘Blue Fortune’ is a hybrid of Agastache foeniculum and A. rugosa, bred and selected at Arboretum Trompenberg in the Netherlands. It blooms over a long period. The foliage has the scent of licorice. Largely untested on the prairies, it is worthy of trial in a protected location. ‘Golden Jubilee,’ a 2003 All-America Selections winner, has similar parentage. The leaves are lime-green to chartreuse. It overwinters in warmer regions of the prairies and selfseeds everywhere.

Agastache ‘Golden Jubilee’ has blue flowers and limegreen to chartreuse foliage. Best to deadhead to prevent prodigious self-seeding.

CARE: Place in full sun and well-drained soil. Allow to moder-

ately reseed. USE: Useful in borders, herb gardens and for cutting, it attracts bees, butterflies and hummingbirds.

Windflower, snowdrop anemone (Anemone sylvestris)

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Native to Europe, snowdrop anemones produce single, pure white, nodding flowers in early spring. It is lovely, but place with caution. Once at home, it is difficult to dislodge. The plants are up to 40 cm (15 in.) in height, with attractive foliage. ‘Flore Pleno’ is a double form that resembles a white pompom chrysanthemum. It is equally tough. CARE: Windflower will grow in sun or shade in a wide range

of soils. USE: It self-seeds too readily to be part of a formal border and is best left to naturalize in an area where it can reseed without becoming invasive: under birch, apple or plum trees or in a wild or shade garden. It is excellent as a ground cover.

A wonderful ground cover in sun or shade, windflower or snowdrop anemone (Anemone sylvestris) is far too invasive for a border.

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Pussytoes, antennaria (Antennaria spp.)

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Pussytoes forms a low, woolly, grey green mat of 5 to 8 cm (2–3 in.) with pink flowers in June. Several species (such as Antennaria aprica) are native to the prairies, where both pink- and whiteflowered forms are found and are well worth growing if you can find them in your pasture or at a specialty native plant nursery. But it is the European species (A. dioica) that is generally commercially available. Antennaria is from the Greek word for antennae. The male flowers, produced on separate plants, have fine, short hairs with swollen tips similar to antennae. A. aprica is a white species more commonly found in the wild. A. dioica ‘Rubra’ forms a prostrate ground cover, 10 to 15 cm (4–6 in.) in height, with soft silver foliage and wine-red flowers in June and July. Pussytoes (Antennaria aprica) is a diminutive, mat-forming native perennial with soft grey foliage and white flowers – an excellent pavement planting.

CARE: Plant in well-drained soil in full sun. It spreads by stolons

and needs dividing and replanting every few years. Deadhead after flowering. USE: Often used in dry bouquets, pussytoes is planted in rock gardens and among paving stones along an informal path as a “pavement planting.”

Arabis, rockcress (Arabis caucasica, syn. A. albida)

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Arabis is a long-lived addition to the spring garden that’s easy to grow from seed. It is covered with masses of tiny white or pink flowers in May which practically conceal the soft grey green evergreen foliage. A member of the mustard family and native to southeastern Europe, Turkey and Iran, arabis is a trailing, mat-forming plant, only 15 to 20 cm (6-8 in.) in height. Rockcress is available in both white and pink forms. ‘Compinkie’ (A. arendsii) is light to dark pink, 15 to 20 cm (6–8 in.) in height. ‘Plena’ is fully double, sterile, long blooming and produces no seedlings. ‘Rosea,’ with a height and spread of 15 by 30 cm (6 x 12 in.), has light pink flowers. ‘Compinke’ rockcress (Arabis arendsii) has white or pink flowers, is easy to grow from seed, and is ideal for rock gardens.

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‘Snowcap’ is a single, white-flowered cultivar of 30 cm (12 in.) or less. ‘Snow White’ has single white flowers.

Variegated forms are useful for their foliage but are less floriferous and usually less vigorous. They may die on you for no apparent reason. A. caucasica ‘Variegata’ has green and creamy-white leaves but is prone to reverting back to green. If this happens, the green parts should be removed. A. ferdinandi-coburgi ’Variegata’ with white flowers, is worthy of trial in protected locations but suffers from dieback in colder areas of the prairies. CARE: Plant in full sun to partial shade in well-drained soil. For

a tidier look, shear after flowering. Flea beetles may be a problem in areas where canola is grown. USE: Arabis is ideal for rock gardens, slopes, edging, the front

of the perennial border, as a ground cover or as a pavement planting. Plant it where you will enjoy the fragrance. It is a food source for butterfly larvae.

Mountain sandwort (Arenaria montana) It is nice to see that a few seed houses and nurseries carry this lesser-known plant. Arenaria is from the Latin word arena (where

Rockcress (Arabis caucasica) needs only full sun and well drained soil to live for many years.

sports are played), which means sand. Its natural habitat – the Alps – should tell us something about its need for sharp drainage. It is related to pinks (Dianthus) but its flowers resemble those of snow-in-summer, although its habit is more contained and its form is almost pillow-like. It produces pure white flowers above a grey green mat-like cushion, 20 cm (8 in.) in height, in early spring. ‘Avalanche’ has moss-like foliage and white flowers. ‘Grandiflora’ has needle-like foliage with large white flowers. CARE: Place in full sun and well-drained soil. USE: Plant in rock gardens or allow to cascade over low walls.

Thrift (Armeria spp.)

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Common thrift (Armeria maritima), native to coastal cliffs of Europe and therefore salt tolerant, is easy to grow and was once used medicinally to treat a wide range of problems, including obesity. It has pink flowers in late spring. Many cultivars have been selected from the species, but the species is longer lived and more dependable.

An early spring bloomer, mountain sandwort (Arenaria montana) has a cushion-like form and white flowers above grey-green foliage.

‘Alba’ is white.

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‘Dusseldorf Pride’ is a deep reddish-pink with larger flowers. ‘Nifty Thrifty’ has variegated green-and-white foliage with pink flowers but hasn’t been widely tested on the prairies. ‘Rubrifolia’ has burgundy foliage in spring that later turns to green and magenta-pink flowers. ‘Splendens’ has bright rose flowers over low mounds of grassy foliage. ‘Vesuvius’ sports dark purple foliage and bright pink flowers. Spanish thrift (A. juniperifolia) is native to Spain and forms tight hummocks or cushions with evergreen juniper-like foliage and almost stemless soft pink flowers in the spring. ‘Laucheana’ sea thrift, a cultivar of A. lauchenana ‘Splendens,’ has pink flowers above grassy foliage. CARE: Plant in full sun in very well-drained soil. Deadhead for Thrift (Armeria spp.), native to the coastal cliffs of Europe, has white or pink flowers and works well in a rock garden or the front of a border.

prolonged bloom. USE: Use in rock gardens, as edging, at the front of the border

and in containers.

Artemisia, sage (Artemisia spp.)

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Here is a diverse genus containing perennials as well as shrubs. Among them are ornamental garden plants, culinary species and the notorious absinthe. Most are grown for their aromatic silver foliage with its sage-like smell. The flowers are generally inconspicuous. The genus was named after the Greek goddess of chastity, Artemis. Silver sage (Artemisia ludoviciana) is an upright plant, 60 to 75 cm (24–30 in.) in height and grown primarily for its foliage. The species name, ludoviciana, means of Louisiana, one of the areas where it is found in North America. ‘Silver King’ has attractive but undivided grey foliage and a bushy, upright form, 60 to 90 cm (24–36 in.) in height. ‘Silver Queen’ is 75 cm (30 in.) in height with slightly wider, pointed leaves with a deeply cut, jagged, irregular margin. It is invasive and is best used for naturalizing. ‘Silver Brocade’ (Artemisia stelleriana) is well behaved, with deeply lobed silver grey leaves and great drought tolerance.

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‘Valerie Finnis’ is a more recent introduction, largely untested on the prairies, with broad leaves and a compact form, 45 to 60 cm (18–24 in.) in height. It is perhaps less aggressive. Cut back for a neater appearance if it sprawls.

CARE: Silver sages tolerate poor, sandy soils, drought and full

sun. They spread by stolons. USE: Naturalize in areas where other plants simply will not

grow. In a border they are too invasive unless physically contained. The foliage is useful in dried arrangements.

’Silver Mound’ artemisia (A. schmidtiana) forms a compact, mound-like plant, 30 cm (12 in.) in height with a spread of 45 cm (18 in.). It seldom stirs from where it was originally planted. The foliage is soft, finely cut and almost misty silver grey, with typical sage-like fragrance. CARE: It does well in sandy, well-drained soils in full sun and is

quite drought tolerant. When grown in shade or under more fertile conditions or with too much water, it tends to lose its compact form. It may be sheared in midsummer for a neater appearance and to remove the unattractive seed heads. It occasionally dies out for no apparent reason. USE: ’Silver Mound’ is excellent in rock gardens, as an edging plant and towards the front of the perennial border. ’Silver Brocade’ artemisia (A. stelleriana, syn. ‘Boughton Silver’), although native to northeast Asia, is naturalized over parts of North America. It was named for the German naturalist Georg Wilhelm Stellar (1709–1746), who brought it from Siberia. ‘Silver Brocade’ was introduced by the University of British Columbia Botanical Garden. It is a low (15–30 cm/6–12 in.), compact selection with deeply lobed,

A. ludoviciana has attractive silver leaves and varies from 60 to 75 cm (24–30 in.). It is an aggressive plant best suited for naturalizing in difficult situations.

silver grey leaves. It thrives in heat and almost gleams at dusk. CARE: Plant in full sun in well-drained soils. To prevent self-

seeding, shear plants after flowering, before seeds set. USE: It is extremely useful for edging, as a ground cover in dif-

ficult, dry situations, for naturalizing, to hold slopes and in pots or hanging baskets.

Swamp milkweed (Asclepias incarnata)

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For a plant with the common name of swamp milkweed, this one is exceedingly drought tolerant and vigorous in the driest of situations. I can only imagine it in a swamp. Native from Nova Scotia to southeastern Saskatchewan, its genus name is from the Greek asklepios, the god of medicine, referring to its ancient medicinal properties, while incarnata means flesh pink and describes the flowers.

‘Silver Mound’ (A. schmidtiana) is refined and well behaved. If you let it spend the summer in a container, be sure to overwinter it in a ground bed.

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Showy white or pink flowers are borne on 60 to 90 cm (2–3 ft) stems in early summer above 8–15 cm (3–6 in.) alternate leaves. ‘Carmine Rose’ has rose-pink flowers. ‘Cinderella’ is a dusty rose-pink. ‘Ice Ballet’ is white. ‘Milkmaid’ has white flowers. ‘Soulmate’ has white flowers with rose pink bracts. CARE: Swamp milkweed is very adaptable to varying soil and

moisture conditions. Plant in full sun. It will spread if conditions are to its liking. USE: This is an important food source for the larvae of monarch butterflies. It is a good border plant, cut flower and bog plant.

Basket-of-gold, perennial alyssum (Aurinia saxatilis)

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Producing a mass of gold each spring, alyssum is easily grown from seed and will live for several decades if given full sun and ‘Cinderella’ (Asclepias incarnata) is amazingly drought tolerant for a plant with the common name of swamp milkweed. Its flowers are a dusty rose pink.

well-drained soil. Originally named Alyssum saxatile by Linnaeus in 1752, alyssum is native to Europe and Asia Minor. Aurinia is Latin for golden and refers to the flowers. Saxatilis means growing among rocks and alludes to its native habitat. It is a low, mound-like plant of 25 to 30 cm (10–12 in.) with a spread of 30 to 60 cm (12–24 in.). Its grey green leaves are covered with masses of golden-yellow flowers for four to six weeks in May and June. ‘Citrinum’ has lemon-yellow flowers on a more compact plant, 30 to 38 cm (12–15 in.) in height. It is shorter lived than the species. ‘Compactum’ is a dwarf form of 20 cm (8 in.). CARE: Full sun and good drainage are essential. The species

has greater longevity than the cultivars. Shear after flowering for a neater appearance. Do not overfertilize. USE: Alyssum is ideal for perennial borders, rock gardens, as a ground cover or among paving stones or patio bricks.

Easy to grow from seed and long lived, perennial alyssum (Aurinia saxatilis) blooms for four weeks or more in late spring.

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False indigo, wild blue indigo (Baptisia australis) An extract from the flowers was once used as a substitute for the blue dye indigo, hence the common and genus names – Baptisia comes from the Greek word meaning to dye. Australis

means south and presumably refers to part of its native habitat in the southeastern United States. A legume, false indigo has blue, pea-like flowers that bloom in May and June and somewhat resemble lupines. The inflated seed pods that follow are black, curled and decorative. It is about 1 m (3 ft) in height, with an arching, upright form. The trifoliate blue green leaves are compound and remain attractive until hard frost. It is long-lived, with thick, strong roots, but may take several years to develop and come into bloom. It is best placed in a protected location. ‘Solar Flare’ is a new, largely untested open-pollinated hybrid worthy of trial in protected locations. The flowers open lemon-yellow, changing to a rusty orange blush.. CARE: Plant in full sun on well-drained soil. It does not tolerate

root disturbance once established. USE: Use in perennial or mixed borders, as a specimen plant and in wild gardens. Both the flowers and seed pods are used in arrangements. It is a nectar plant for butterflies.

Heart-leafed bergenia, pigsqueak (Bergenia cordifolia)

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Here is a workhorse of a perennial that requires little on the

False indigo (Baptisia australis) has startling blue flowers in May and June that were once used as a dye.

part of the gardener, propagates readily from division, lives for decades and has a long season of interest. Named after Karl August von Bergen (1704–1768), a Frankfurt botany professor, bergenia was introduced into Europe from Siberia in the seventeenth century. Cordifolia means heart-shaped and describes the leaves. If rubbed between your thumb and forefinger, the leaves make a sound like the squeak of a pig, thus the common name. The 30 cm (12 in.) spikes of pink to purple flowers are produced in May. The large, handsome, leathery, evergreen leaves (which turn a reddish bronze in autumn) resemble waxy cabbage leaves. Depending on growing conditions and weather, the flowers are produced either above or within the foliage. The root is thick and deep. A number of cultivars are available, varying from white to almost red flowers, but these are not as hardy, robust or long lived as the species. Most are hybrids developed in Europe from less-hardy parentage. Among them are the Bressingham hybrids, which might do best in a more protected location. ‘Eroica’ was selected for its beet-red fall foliage. Bergenia crassifolia, native from Siberia to northwest China, is similar to B. cordifolia but with slightly smaller, spoon-shaped leaves and flowers that are held higher above the foliage. It is not as hardy and is less robust.

Heart-leafed bergenia (Bergenia cordifolia) is a work horse of a perennial – hardy, drought tolerant, long lived and at home in sun or shade.

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B. stracheyi ‘Pink Dragonfly’ has narrower foliage and a finer texture. Largely untested, it is best placed in a protected location. CARE: Extremely adaptable, bergenia is equally at home in

full sun or shade and dry or moist soil. It is easily propagated by division. Divide every four years to prevent overcrowding. USE: It is used in perennial borders, rock gardens, as an edging plant, underplantings below trees, a ground cover, a waterside planting and in arrangements.

‘Skinner’s Golden’ bromegrass (Bromus inermis ‘Skinner’s Golden’)

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The species, introduced from Europe, is widely planted as a pasture crop and has escaped from cultivation in much of North America. ‘Skinner’s Golden’ was selected near Dropmore, Manitoba for its bright yellow-with-green var‘Eroica’ bergenia (B. cordifolia) was selected for its outstanding bright red fall foliage.

iegated foliage. It is about 60 cm (24 in.) in height, with a graceful, arching form. CARE: For the best colour, grow in full sun in ordinary soil.

Remove any sections that revert to green. It is a cool-season grass that performs best in early summer and fall. Mow or clip if it becomes ragged during the heat of midsummer. USE: Mass plant as a transition area between the manicured

area of a rural yard and surrounding bush or use it to hold a bank or slope or as a ground cover. If placed in the border, it must be contained, as it spreads rapidly by rhizomes. Remember, bromegrasses are vigorous and aggressive and the burden of responsible placement lies with the gardener.

Bellflower (Campanula spp.) With our sunny days and cool nights, bellflowers do very well on the prairies. Campanula is Latin for small bell and describes the bell-like flowers, generally available in blue and white. Carpathian bellflower (Campanula carpatica) is dependable, moderately long-lived, easily grown from seed and adaptable in use and habitat. The species name, carpatica, indicates its origin, the Carpathian Mountains. The blue, upfacing flowers, 2.5 to 5 cm (1–2 in.) in diameter, bloom for a long period in midsummer. They are held above a neat, compact mound ‘Skinner’s Golden’ bromegrass (Bromus inermis) is a great plant for naturalizing but far too aggressive for a border.

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of dark green foliage of 30 cm (12 in.). ‘Blue Clips’ has blue flowers and a compact form.

‘Deep Blue Clips’ has a darker shade of violet-blue flowers. ‘White Clips’ is similar with white flowers. CARE: Grow in full sun or partial shade on well-drained soil.

Deadheading prolongs bloom. USE: Carpathian bellflowers are ideal for the front of the bor-

der, rock gardens and edging. Dwarf bellflower (C. cochleariifolia, syn. C. pusilla), a diminutive perennial from the mountains of Europe, is a lot tougher than it looks. The bright green foliage, only 8 to 10 cm (3–4 in.) in height, is almost hidden by a myriad of tiny, outfacing, bell-like blue flowers in June and July. It spreads rapidly by creeping rhizomes, soon forming a solid mat, but is easily controlled. ‘Alba’ is a white form. ‘Bavarian White’ has single flowers. ‘R. B. Loder’ has double, soft blue flowers that fade to white. CARE: Grow in sun or partial shade in well-drained soil. USE: This is an excellent plant for edging, rock gardens,

ground covers, pavement plantings, cascading over walls, in crevices and on garden steps.

Weather thistle (Carlina acaulis subsp. simplex)

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‘Blue Clips’ is one of the most popular cultivars of the Carpathian bellflower (Campanula carpatica) and does equally well in sun or partial shade.

This is one of the weirder looking but intriguing perennials you are apt to come across. It’s a plant that invites comments, but finding it may be a problem. The genus name arose in the Middle Ages when Charlemagne (Carolina) used this thistle in an attempt to treat the plague that was decimating his soldiers. The common name is derived from the fact that the flowers close on a cloudy day. Native to Europe and the Alps, it has been grown in British gardens since 1640. Low, with a height and spread of 30 cm (12 in.), shortstemmed and thistle-like, it has bronzy-green, pinnately lobed foliage and enormous white-purple flowers with showy, dry, silvery bracts in late summer. CARE: Plant in a hot, dry but sheltered location. Once estab-

lished, it is long lived but does not transplant easily due to its deep taproot. USE: Use in rock or gravel gardens and as a cut flower.

The weather thistle (Carlina acaulis subsp. simplex) always elicits comments with its enormous papery flower on such a short stem.

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Cupid’s dart (Catananche caerulea) The Greeks were said to have used cupid’s dart as an aphrodisiac (which accounts for its common name). It was later used to symbolize a purer sort of love. Native to the dry meadows of southern Europe, it is a short-lived perennial but blooms its first year from seed. The basal foliage is grey and woolly, about 45 to 70 cm (18–28 in.) in height, forming a neat clump. The papery, daisy-like flowers, 5 cm (2 in.) in diameter, are somewhat like a cornflower, a lovely blue with a darker blue centre and prominent darker veins. They are borne on long stems in midsummer. The flower buds are silvery. ‘Alba’ is white. ‘Bicolour’ has white petals marked with flecks of metallic blue. The lovely blue papery flowers of cupid’s dart (Catananche caerulea) were once believed to have aphrodisiac properties.

‘Major’ has lavender-blue flowers. CARE: Plant in full sun in well-drained soil. Keep on the dry side.

In colder areas of the prairies, place in a protected location. USE: Use as cut flowers and in borders.

Centaurea (Centaurea spp.) Globe centaurea (Centaurea macrocephala)

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is generally

grown for the cut or dried flower market and is undervalued as a taller perennial for the border. The genus is named for the mythical Greek centaurs, creatures with the lower body of a horse and upper torso of a man, who were said to have used this plant medicinally. Native to Armenia and the Caucasus Mountains, globe centaurea is easily identified by the overlapping paper-like brown bracts below the petals. Macrocephala means large head, a reference to the large (8–10 cm/3–4 in. diameter) yellow, thistle-like flowers borne in late summer through fall. Up to 1.2 m (4 ft) in height, the plants are rather coarse, with long, wavy, green leaves. NOTE: This is a prohibited noxious weed in Alberta. CARE: Grow in full sun in well-drained soil. It resents disturbance

once established. Deadhead to prevent unwanted seedlings. Although grown primarily for the cut flower market, globe centaurea (Centaurea macrocephala) is also well placed toward the back of a perennial border.

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USE: Place at the back of perennial or mixed borders, use as specimen plants or mass in large groups. It is used in both fresh and dried arrangements.

Perennial cornflower (C. montana) has graced prairie gardens

almost from the beginning of settlement. The species name, montana, refers to its native habitat, the mountains of southeastern Europe. The globular, thistle-like, tubular blue flowers, 2.5 to 5 cm (1–2 in.) in diameter, have a reddish centre and are held on 60 cm (24 in.) stems above grey green foliage. They bloom profusely in June, with less intensive flowering later. ‘Rosea’ is a pale pink form. The following cultivars are largely untested in the colder areas of the prairies but are worthy of trial: ‘Amethyst Dream’ is shorter (30–40 cm/12–16 in.) with amethyst flowers. ‘Amethyst in Snow’ is more compact, with silver-green foliage and white petals with a dark purple centre. ‘Gold Bullion’ is similar to the species but with goldenyellow foliage. Remove foliage that reverts to green. CARE: Grow in full sun or partial shade in most soils. They may

require occasional containment with a sharp spade. Deadhead to prevent self-seeding. If stems are cut back after the first flowering, it may flower again in late summer.

Grow the perennial cornflower (Centaurea montana) in full sun or partial shade in an informal border or for naturalizing. It’s a nectar source for butterflies and bees.

USE: Because it self-sows and spreads by stolons, perennial corn-

flower is best in an informal border or for naturalizing. It is used as a cut flower and is a nectar source for butterflies and bees.

Giant cephalaria (Cephalaria gigantea, syn. C. tatarica)

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The common and botanical names say it all: It’s a giant of a plant with yellow flower heads – about the same height and form as giant fleeceflower (Persicaria polymorpha) but with a much more delicate and airy appearance. Don’t let its looks fool you, though. It is one tough perennial. The genus name is from the Greek words kephala (head) and gigantea (very large), indicating that the flowers are borne in large (5 cm/2 in.) heads. Native to the Caucus Mountains, the plants can easily reach 2 m (6 ft) or more. The foliage is pinnately compound and the leaflets have toothed margins. The soft primrose yellow flowers, held on thin waving stems in late summer, are 5 cm (2 in.) in diameter and resemble scabiosa. It attracts many pollinators. CARE: Plant in full sun or very light shade in well-drained soil.

Deadhead to prevent self-seeding, which this plant will otherwise do with great abandon. USE: Place at the back of the border.

Giant cephalaria (Cephalaria gigantea) can easily reach 2 m (6 ft) or higher. The soft yellow flowers look like scabiosa.

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Snow-in-summer (Cerastium tomentosum)

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Another workhorse of a drought-tolerant perennial, we tend to look down on snow-in-summer simply because it’s so durable and dependable. But what’s wrong with a compact carpet of tiny silver leaves that’s almost totally hidden when the white flowers are in bloom in early summer? A member of the carnation family, it was introduced from Italy. The genus name, Cerastium, is from the Greek word for horn, a reference to the shape of the seed capsule. Tomentosum means hairy and describes the silver grey leaves. The common name is derived from the masses of tiny white flowers produced in June. Each flower has five petals that are so deeply divided there appear to be ten. A mat-forming plant (20 cm/8 in. in height), it will spread by stolons and seed. Woolly snow-in-summer (Cerastium alpinum) is shorter and denser with a woolly appearance. It demands perfect drainage. CARE: Plant this tough perennial in full sun in poor, well-

Snow-in-summer (Cerastium tomentosum), easily grown from seed, forms a compact mound of tiny silver leaves hidden by white flowers in early summer.

drained soils. Shear after flowering for a neater appearance and to prevent unwanted seedlings, which appear especially in gravel paths. USE: It is excellent as a ground cover, on slopes or trailing over

walls. It has overwintered in large containers in sheltered areas. In a rock garden or perennial border, it may be too aggressive.

Golden marguerite, anthemis

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(Cota tinctoria, syn. Anthemis tinctoria)

Although short-lived (about two to three years) on the prairies, golden marguerite generally perpetuates itself through seeding. Treat it as you would a biennial and forego the mulch. Native to Europe and Asia, golden marguerite produces masses of yellow daisies, 2.5 cm (1 in.) in diameter, in June and July on plants about 60 cm (24 in.) in height. The species name, tinctoria, refers to its former use as a dye source. ‘Kelwayi’ has golden-yellow flowers with a darker eye. The foliage is aromatic, dark green and finely divided, on 60 cm (24 in.) plants. ‘Moonlight’ has pale yellow flowers. They do well in poor soil and full sun, but golden marguerites (Cota tinctoria) are short-lived. They propagate through selfseeding so forego the mulch.

‘Sauce Hollandise’ is a sulfur yellow and more compact. The species Anthemis sancti-johannis has orange flowers and is compact and slightly smaller. Although not widely grown on the prairies, it is worthy of trial in protected locations.

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CARE: Well adapted to poor soil and full sun, it does not need

fertilizer. Cut back after flowering and divide or thin out every three to four years. USE: Anthemis is ideal as a cut flower and for naturalizing in areas beyond the reach of a garden hose – a dry bank or a back lane. It self-seeds too generously for a formal border and seedlings may be inferior to the cultivars.

Pinks (Dianthus spp.) Maiden pinks (Dianthus deltoides) is an old-fashioned plant native from Scotland to Asia. It forms large mats, 8 to 15 cm (3–6 in.) in height, covered in tiny, deep pink flowers for six weeks in midsummer. Deltoides is from the Greek word delta (triangular), a reference to the shape of the petals. The dark green, grass-like foliage makes an attractive ground cover. ‘Albus’ is a white cultivar with bright green foliage.

‘Brilliant’ maiden pinks (Dianthus deltoides) have dark red flowers and dark green to bronzy green foliage.

‘Arctic Fire’ has a mounded form of 20 cm (8 in.) and white petals with a bright, cherry red eye over dark green foliage. ‘Brilliant’ has dark red flowers with dark green to bronzy foliage. ‘Flashing Lights’ is mat-forming, 15 cm (6 in.) in height, with ruby-red flowers on wiry stems and dark foliage. ‘Zing Rose’ is bright red with an upright habit (20 cm/8 in.) and repeat bloom; it is good for containers. CARE: Plant in full sun on well-drained soils. Shear after flow-

ering for a neater appearance. They are relatively short-lived but generally bloom their first season from seed and usually self-sow. Taking cuttings ensures their continuity. USE: Maiden pinks are excellent in rock gardens, as an edging or

ground cover and among paving stones as a pavement planting. Grass pinks (D. plumarius) Although grass pinks tend to be relatively short-lived, their lack of longevity is compensated for by their beauty, fragrance and ability to flower their first year from seed and then self-seed. The species from which most varieties originate are native to central and eastern Europe. These are old-fashioned plants that have graced gardens for centuries. Many cultivars are crosses between species and their hardiness varies. Some are of unknown origin.

Grass pinks (D. plumarius) are taller with more bluegreen or grey foliage. They are called pinks because the petals appear to have been cut with pinking shears.

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The grassy, blue green or grey foliage ranges in height from 15 to 60 cm (6–24 in.) and is attractive throughout the growing season. The fragrant flowers are produced from May to July and vary from white to pink to red, including bicolours, usually with fringed petals. The common name, pinks, describes the petals, which appear to have been cut with pinking shears. Ballad blend (30 cm/12 in.) has fully double, large, lightly scented flowers in a full colour range with darker centres. Spring Beauty mix has double flowers in rose, salmon, pink and white. ‘Sweetness’ is compact, 20 cm (8 in.) in height with a spread of 30 cm (12 in.), with showy, fragrant flowers in pink to rose to red. The fragrant flowers of grass pinks (D. plumarius) bloom from May to July and vary from white to pink to red, including bicolours.

Allwood pinks (Dianthus x allwoodii), a group of interspecific hybrids (crosses between two species) raised by English nurseryman Montague Allwood in the 1920s, have D. plumarius in their parentage and are also included here. Their foliage is generally grey green and they are both compact and vigorous. Many are double. Some may be less hardy. All are relatively short-lived but will reseed. ‘Frosty Fire’ has deep ruby red, fringed flowers and silverblue foliage of 10 to 15 cm (4–6 in.). Cheddar pinks (D. gratianopollitanus), named for the Cheddar Gorge in England, include: ‘Firewitch’ has magenta flowers with a lacy fringe over blue green foliage (15 x 25 cm/6 x 10 in.). ‘Spotty Cheddar’ has pinky-red flowers with white spots and is 15 to 20 cm (6–8 in.) in height. ‘Tiny Rubies’ has tiny pink flowers on compact mounds of 10 cm by 20 cm (4 x 8 in.) and is one of the best. CARE: Grow in full sun in well-drained soil. Shear after flowering for a neater appearance. The evergreen foliage benefits from snow cover. USE: Use as cut flowers, in rock gardens or the perennial

border, as a fragrant edging and among paving stones. ‘Fire Witch’, a cultivar of Cheddar pinks (D. gratianopollitanus), has magenta flowers with a lacy fringe.

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Gasplant (Dictamnus albus) The flower buds or seed heads of gasplant will indeed “light up” if lit by a match on a warm evening. I’ve tried it and it works. It was the only time my then pre-teen son has ever expressed an interest in horticulture. Long-lived and attractive, gasplant deserves much greater use. This perennial will grace your garden for sixty years or more. The handsome, pinnately compound leaves are dark green and glossy. Racemes of white or pink flowers are produced on 1 m (3 ft) stems in June. It always looks unsubstantial and a bit worse for wear on garden centre benches but is worth the wait. Named after Mt. Dicte in Crete, gasplant is native from southern Europe to northern China. Albus means white, describing the flowers. The common name alludes to the volatile oils that give the plant a pungent, lemon-like fragrance and may cause skin inflammation or blistering in sensitive individuals. Plant parts are poisonous if ingested. Dictamnus albus var. purpureus has purple-pinkish flowers. CARE: Gasplant does well in a loamy soil in full sun and is

drought tolerant after two or three seasons. Although transplants and seedlings appear wimpy and seem to struggle for their first few years, they will come into their own by their third or fourth season. They are best moved to their permanent location by their second summer.

Gasplant (Dictamnus albus) has pink or white flowers and can live for 60 years.

USE: Use as specimen plants and in perennial or mixed borders.

Draba (Draba sibirica, syn. D. repens)

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Not at all “draba,” in spite of its common name, it is a gentle explosion of yellow in early spring. There are many draba species, most of them alpine, found in North America, Europe and Asia. This one is from Siberia and very hardy and long-lived. Tiny yellow flowers, each with four petals, appear over a cushiony mat, 5 cm (2 in.) in height with a spread of 20 cm (8 in.) of very tiny leaves in early spring. Draba dedeana and D. aizoides are species that may be difficult to source, but have done well on the prairies. CARE: Place in full sun on well-drained soil. USE: Use in rock gardens.

A tiny alpine cushion of a plant, draba (Draba sibirica) has lovely yellow flowers in early spring.

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Dragonhead (Dracocephalum grandiflorum, syn. D. rupestre) Dragonheads are a very variable genus, from rampant spreaders to neat little plants. In the latter category, this one is hardy and worthy of a place in our gardens. Native to China, the genus is from the Greek words draco, meaning dragon and cephale, head, describing the shape of the flowers. The species name, grandiflorum, indicates that the flowers are large. A member of the mint family, its leaves are opposite each other on the square stems. The large, deep blue to purple flowers are found in whorls on the reddish stems in early summer. The foliage is grey green and the plants are 30 cm (12 in.) in height and spread. Dracocephalum ruyschiana is taller, up to 60 cm (24 in.). CARE: Place in full sun to partial shade in well-drained soil. USE: Use in the front of the border or in rock gardens. As its names imply, the bright blue flowers of dragonhead (Dracocephalum spp.) resemble the head of a dragon.

Purple coneflower (Echinacea purpurea) A veritable explosion of interspecific (hybrids with parentage from different species) coneflower cultivars has hit the horticultural market in the last decade, moving the coneflower from the roadside ditches of the central United States into virtually everyone’s garden. Not all of these new introductions have proven hardy and durable in the prairies, but some of them have. The genus name is from the Greek echinos, meaning hedgehog, describing the prickly flower base. The daisy-like flowers have drooping purple petals and a raised central cone, generally of brown to orange. The upright clumps are about 1 m (3 ft) high and 60 cm (24 in.) wide with alternate, dark green leaves. They bloom from late summer to fall. Hardy to zone 3, they benefit from a protected location in colder areas of the prairies, but most will bloom their first season from seed. Even the species is short-lived. The cultivars are well worth replacing when they begin to decline. Yellow and orange cultivars appear to be the shortest-lived. ‘Coconut Lime’, a newer untested variety, has double white flowers on a compact plant of 50 cm (20 in.). ‘Double Delight’ has fully double, tufted pink flowers. ‘Green Jewel’ has fragrant, light green flowers on compact

‘Powwow Wild Berry’ is a new coneflower (Echinacea purpurea) cultivar with spectacular flowers, but is largely untested on the prairies.

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plants. ‘Kim’s Knee High’ is a dwarf plant of 45 to 60 cm (18–24 in.) with pink flowers.

‘Lucky Star’ has white horizontal petals surrounding an orange disk. ‘Magnus’ has a bushier form with large, reddish-purple, horizontal (rather than drooping) petals. ‘Prairie Splendor’ is earlier with large, deep rose flowers. Primadonna series have strong stems and large, deep rose or white flowers. ‘Ruby Star’ is an improved late summer red. ‘Twilight’ has butter yellow rose petals around a red cone and is fragrant. ‘Vintage Wine’ has purple-red flowers on strong, bushy plants. ‘White Swan’ has white petals around a yellow green cone. CARE: Place in full sun in a well-drained but not too rich soil.

Deadhead to prolong bloom. USE: Use in borders and for cut flowers in fresh and dry

arrangements. They attract butterflies and birds.

Globe thistle (Echinops ritro)

‘Magnus’ coneflower (E. purpurea) is an older introduction which, along with ‘White Swan, has a 3–4 year life span in zone 2.

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A thistle is not an easy plant to market in rural areas of the prairies, even if it is as singularly attractive as this. Echinops comes from the Greek word for hedgehog and aptly describes its spiny nature. Native to Europe and western Asia, it is 1 to 1.2 m (3–4 ft) in height, with large, 2 to 5 cm (1–2 in.), globular, steel blue flowers that shimmer and glow in late summer. The thistly foliage has wavy to lobed margins with a silver underside. ‘Taplow Blue’ has 5 cm (2 in.) steel blue flowers. ‘Veitche’s Blue’ is 90 to 100 cm (36–40 in.) in height and produces smaller flowers in a lighter, more silvery blue. ‘Blue Glow’ (Echinops bannaticus) is a large (1.2 x 1.2 m/4 x 4 ft), sturdy plant with good winter interest. ‘Star Frost’ (E. bannaticus) is 90 x 60 cm (36 x 24 in), and has pure white flowers. CARE: The globe thistle is at home in poor soil and full sun. USE: A large plant, it is well suited to the back of a border,

for naturalizing, as a specimen plant and as a dried flower. It attracts bees and moths and is a nectar plant for butterflies.

Globe thistle (Echinops ritro) has globular, steel blue flowers and thistly foliage. ‘Blue Glow’ is a large sturdy plant with good winter interest.

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Fleabane (Erigeron speciosus)

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A member of the composite family and resembling asters, the species is native to North America (including the prairies). Cultivars are generally interspecific hybrids. The common name stems from the former use of the dried flowers as a flea repellant. Upright, well-branched plants of 50 to 75 cm (20–30 in.) produce small, 2.5 to 5 cm (1–2 in.), pink, blue or purple daisies with yellow centres in late spring or early summer. Lance-like leaves clasp the upper stems. ‘Azure Fairy’ has a height and spread of 60 cm (24 in.), mauve petals and a long bloom period. ‘Blue Beauty’ (‘Schoene Blaue’) has a mounding form, with a height and spread of 75 by 50 cm (30 x 18 in.) with blue flowers. ‘Pink Jewel’ is 75 cm (30 in.) in height, with flowers in various shades of pink. As the common name implies, the dried flowers of fleabane (Erigeron speciosus) were once used as a flea repellant.

CARE: Plant in full sun in well-drained soil. With too much fertility, water or shade, stems become floppy. USE: This is an excellent perennial for either rock gardens or borders or as a cut flower. It is a nectar source for butterflies.

Sea holly (Eryngium spp.)

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Sea holly resembles a metallic, blue-grey coneflower with a silvery, ruff-like bract at its base. The foliage is glossy, deeply cut and very spiny. They bloom in July, holding their flowers until frost. Alpine sea holly (Eryngium alpinum), from the Alps, is 60 to 90 cm (24–36 in.) in height, with larger blue flowers and heart-shaped leaves. It adapts to partial shade. ‘Blue Star’ is 70 to 80 cm (28–32 in.) in height. Amethyst sea holly (E. amethystinum), native to Europe, has silver-blue leaves and blue flowers on branching, 45 cm (18 in.), amethyst-coloured stems. Flat-leaved sea holly (E. planum) is the most common species and probably the hardiest. Native to Europe and Asia, it is 1 m (3 ft) in height, long-lived, with heart-shaped leaves and small flower heads, 1–2 cm (0.5 to 0.75 in.) in diameter. It is ‘Pink Jewel’, a cultivar of fleabane (E. speciosus) has flowers in various shades of pink on 75 cm (30 in.) stems.

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less spiny than the others. ‘Blue Cap’ is a compact selection, 60 to 75 cm (24–30 in.) in height, with a strong blue colour.

‘Blue Glitter,’ with a height and spread of 80 by 60 cm (32 x 24 in.), has small, silvery-blue flowers. ‘Blue Hobbit’ is a dwarf, compact selection of only 30 cm (12 in.) with round flowers on sturdy stems. CARE: Tolerant of poor and saline soils, sea hollies prefer full

sun and perfect drainage. Avoid heavy clay. Colour is less intense in the shade, but is enhanced by our cooler evening temperatures. Deadhead to prevent self-seeding. USE: Use in perennial borders and in fresh and dried arrangements.

Pincushion cactus (Escobaria vivipara var. vivipara, syn. Coryphantha vivipara, Mamillaria vivipara)

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This cactus, native to the prairies, is not an easy plant to handle. Its fleshy stems are covered with spirally arranged bumps, each with a cluster of short, sharp spines. Vivipara means bearing live young and refers to its offshoots. Shaped like a pincushion and 5 to 8 cm (2–3 in.) in height, it produces silky pink to violet-purple flowers with conspicuous yellow stamens in July. The edible but bland fruit is a fleshy brown berry. Plants can form dense colonies 30 cm (12 in.) or more across. They are best obtained from nurseries specializing

Alpine sea holly (Eryngium alpinum), native to the Alps, has large blue flowers and spiny, deeply cut leaves.

in native plants. CARE: Under normal conditions in the border, cacti will soon

rot. Remember their origin and situate them in full sun on very well drained, sandy soils. USE: Cacti are useful in hotter, drier areas of a rock garden that

are inaccessible to small children, pets and sandaled guests.

Cushion spurge (Euphorbia polychroma, syn. Euphorbia epithymoides) Called cushion spurge because of its clump-like dome or mounded shape, it adds a shimmering chartreuse yellow to the early spring garden with its bright greenish-yellow bracts. The genus is named after Euphorbus, physician to an ancient West African king. It is 30 to 45 cm (12–18 in.) in height. The foliage turns red in the fall. The true flowers are insignificant. All plant parts are poisonous if ingested and may cause an allergic skin reaction. ‘Bon Fire’, largely untested on the prairie, has deep burgundy

Shaped like a pincushion and covered with spines, pincushion cactus (Escorbaria vivipara) should be placed far away from children, pets and visitors with sandals.

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leaves with showy chartreuse bracts; the foliage turns a brighter red in fall. It has a height and spread of 40 by 60 cm (16 x 24 in.). Note: Cypress spurge (Euphorbia cyparissias) is listed as a noxious weed in Alberta, Manitoba and Saskatchewan. CARE: Plant in full sun on well-drained soils. Shear after blooming for a neater appearance. USE: Cushion spurge is excellent in rock gardens or borders.

Blue fescue, sheep fescue (Festuca glauca, syn. F. ovina var. glauca)

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It’s hard to believe that such a tough plant is native to southern France (as well as other parts of Europe and Asia). Yet its adaptability has allowed it to naturalize through much of North America. Festuca is Latin for a grass stalk and ovina means of sheep – the species is used for pasture – while glauca describes the waxy coating on the leaves. Cushion spurge (Euphoprbia polychroma) develops bright greenish yellow bracts in early spring that seem to almost shimmer.

It is 15 to 30 cm (6–12 in.) in height, with thin, wiry blue blades that form tight, evergreen, tufted clumps that are very well behaved within a border. The blue flowering stems soon change to light tan. ‘Elijah Blue’ holds its colour year round. ‘Pepindale Blue’ is dense and compact. ‘Skinner’s’ is among the hardiest selections and has attractive golden seed heads that complement the blue foliage. CARE: Plant in full sun or partial shade on well-drained soils. A cool-season grass, it puts on vigorous growth in spring and fall. Divide older clumps every few years. Shear older growth in early spring before the new growth develops. USE: Its neat form lends itself to more formal use, as an accent plant in rock gardens or groupings in the perennial border, as edging, in containers or as a hummocky ground cover.

Gaillardia, blanket flower

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(Gaillardia x grandiflora, syn. G. aristata) Due to intensive breeding, gaillardias have come a long way in Blue fescue (Festuca glauca) is a well behaved clump type ornamental grass of only 15 to 30 (6–12 in.).

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the past few decades. Most hybrids are usually crosses between annual and perennial species. With inherited characteristics of both, they tend to bloom their first year, be relatively short-lived, but have a long flowering season.

The genus name honours French patron of botany Gaillard de Marentonea, while aristata means bearded or with an awn and describes the seed. Gaillardia is native to the North American prairies and the common name suggests colours found in blankets of Indigenous peoples of the American Southwest: from yellow to orange, bronze, maroon, red and burgundy. The daisylike flowers bloom from July until hard frost and require little maintenance. Plants vary from 30 to 90 cm (12–36 in.) in height and have grey green foliage. ‘Arizona Apricot,’ a 2011 All-America Selections winner, has flowers with a yellow edge and an apricot centre. ‘Arizona Red’ is a dwarf selection of 25 cm (10 in.) with deep crimson flowers. ‘Arizona Sun’ has large, 10 cm (4 in.) blooms. The orange petals have yellow tips and brick red centres over bright green, mounded foliage of 30 x 40 cm (12 x 16 in.). ‘Burgundy’ is a deep wine-red and is 1 m (3 ft) in height. ‘Dazzler’ is 40 cm (16 in.) in height with a red centre and yellow petal tips.

‘Arizona Sun’ is a relatively new introduction of blanket flower (Gaillardia x grandiflora).

‘Fanfare,’ with a height and spread of 60 by 80 cm (24 x 32 in.), has tubular, flared petals with yellow tips and a deep red centre. ‘Goblin’ is a more compact, mound-like cultivar of only 30 to 45 cm (12–18 in.) with 10 cm (4 in.) red-and-yellow bi-colour flowers, well suited to the perennial border or rock garden. ‘Golden Goblin’ is similar but yellow. ‘Oranges & Lemons’ is compact (50 x 40 cm/20 x 16 in. in height and spread), with orange-and-yellow flowers. CARE: Blanket flowers are adapted to full sun and well-drained soils, surviving with little care. Leave beds unmulched so plantings can perpetuate themselves through self-seeding. Cutting back flowering stems prior to hard frost encourages new basal buds. They are slow to resume growth in spring, so be patient. Deadhead for more prolonged bloom and a neater appearance. USE: Use in borders or rock gardens, as cut flowers and for

naturalizing. It is a nectar source for butterflies and bees. ‘Burgundy’ is an older blanket flower (G. x grandiflora) cultivar.

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Cranesbill geranium, perennial geranium (Geranium spp.) Cranesbill geraniums form a large genus and the number of species and cultivars can seem overwhelming. As more and more become available to prairie gardeners, we have the task of sorting out the hardy from the tender and the drought tolerant from those in need of even moisture. Geranium is from the Greek word for crane, describing the seed capsules, which resemble a crane’s bill. Caucasian or Iberian cranesbill (Geranium ibericum)

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a vigorous, hardy, drought-tolerant species with violet-blue flowers in early summer, 45 cm (18 in.) in height. Geranium x ‘Johnson’s Blue’

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(G. himalayense x G.

pratense) produces 3 to 5 cm (1.5–2 in.) blue flowers over a long period. The flowers are large and sterile so there is no selfseeding. It spreads by stolons to make an excellent ground cover. It is 35 to 45 cm (15–18 in.) in height and although somewhat sprawly in shade, it is nevertheless effective. ‘Johnson’s Blue’ perennial geranium (Geranium spp.) works well as a ground cover in both sun or shade, but flowers less in deep shade.

Big foot geranium (G. macrorrhizum)

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is native to the

Alps and Carpathian Mountains. It is 30 to 45 cm (12–18 in.) in height, with aromatic, lobed leaves once used by the pharmaceutical industry as a source of oil of geranium. The flowers are magenta. Macrorrhizum means big root and, like the common name, refers to the thick, fleshy rhizomes, which soon form dense, weed-proof mats. ‘Album’ has white flowers with pink to red calyxes. ‘Ingwersen’s Variety’ has pink, darker-veined flowers, 5 cm (2 in.) in diameter. Bloody cranesbill (G. sanguineum) is native to Europe and Asia. A thick rootstock lends it drought tolerance. It is low (30 cm/12 in.) and mound-like. The early summer flowers are a rich magenta over waxy basal leaves. The foliage is dark green, deeply lobed and a deep red in fall. ‘Album’ is clear white and taller than the species. ‘Alpenglow’ is rose red. ‘Max Frei’ is compact, 25 cm (10 in.) in height, with reddish-purple flowers. G. var. striatum (‘Lancastriense’) has large, pale pink

‘Alpenglow,’ a cultivar of the bloody cranesbill (G. sanguineum) is moundlike and rose red.

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flowers with darker veins, forming a wide, 25 by 30 cm (10 x 12 in.), mound. CARE: Plant in full sun to partial shade on well-drained soil.

Divide every three to four years. Prune back after flowering for a neater appearance. USE: Use in perennial or mixed borders, massed, as a ground

cover or under trees. They will tolerate dry shade, but the deeper the shade the fewer the flowers.

Avens (Geum spp.)

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Three-flowered avens, prairie smoke (Geum triflorum). At some point in spring, these plants with their deep pink-purple nodding flowers dominate the dry prairie grasslands. After the flowers fade, the delicate, feathery, smoke-like seed heads from which the second common name, prairie smoke, arises, take precedence, lasting for many weeks. It is native to a large area of the Canadian prairies and into Montana and North Dakota. And if you take care not to overwater it, it is a very successful garden plant Each flower stalk of about 30 cm (12 in.) has three bellshaped blooms, thus the botanical species name, triflorum. The slightly hairy, dark green leaves are pinnately compound and form a mat. CARE: Plant it in full sun to partial shade on well-drained soil.

Remember its origins and, once established, keep it dry. USE: Three-flowered avens works well in a rock garden, at the front of a border and as a ground cover.

A prairie native, three-flowered avens (Geum triflorum) lends a pink cast to the grasslands in spring.

Boris avens (G. ‘Werner Arends,’ syn. G. x borisii, G. coccineum) was named by Wilhelm Schact, a well-known German horticulturist most famous for his writings on alpine plants. As a young man, Schact was employed as head gardener to King Boris II of Bulgaria. While plant hunting in the Rila Mountains with his employer, he found this natural hybrid of G. bulgaricum and G. reptans and named it after the king. Unfortunately, it has a new botanical name, but the common name remains. The single flowers are 2.5 to 5 cm (1–2 in.) in diameter and a bright, unabashed orange scarlet – this is not a plant for the faint of heart. Flowering in late spring, it is about 30 cm (12 in.) in height and spread. The dark green leaves have a prominent terminal lobe. CARE: Grow in full sun to partial shade. USE: Place in rock gardens, the front of a border, “hot” gardens

or use as edging.

The bright orange flowers of Boris avens (G. ‘Werner Arends’) are gorgeous but not for the faint of heart.

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Creeping baby’s breath (Gypsophila repens)

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Gypso means gypsum and philia lover of, alluding to baby’s breath’s preference for basic or alkaline soil (predominant in the prairies), while repens means creeping and describes its growth habit – it’s gorgeous cascading over a low wall. A native of central and southern Europe, it is found in the Alps and Pyrenees. It forms a mound about 15 cm (6 in.) in height with a spread of 1 m (3 ft) and is covered in tiny white flowers in midsummer. All baby’s breath have deep taproots and should not be moved once established. The species is longerlived than the cultivars. ‘Alba’ has clear white, single flowers and is 10 to 15 cm (4-6 in.) in height. ‘Rosea’ has single pink flowers and a height and spread of 10 by 30 cm (4 x 12 in.). Note: Gypsophila paniculata (tall baby’s breath) has been At its best when cascading over a wall, creeping baby’s breath (Gypsophila repens) is covered in a myriad of tiny pink or white flowers.

declared a noxious weed in Manitoba, Alberta and Saskatchewan. It is illegal to plant it. The deep taproot, coupled with its ability to self-seed, has allowed it to escape from cultivation and naturalize in ditches and pasture land. CARE: Plant in full sun on well-drained soils. USE: Use creeping baby’s breath in rock gardens, cascading over low walls, in containers or perennial borders.

False sunflower (Heliopsis helianthoides, syn. H. scabra)

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Another durable perennial, this tall yellow daisy comes into its own in late summer and keeps going until freeze-up. If you walk down the lanes of older neighbourhoods, you will often see this large, 1 to 1.2 m (3–4 ft) plant gracing many gardens. The genus name is derived from the Greek words helios, sun and opsis, resembling, referring to its resemblance to sunflowers. The golden flowers are mostly double. The older species name, scabra, means rough and describes the texture of the leaves and stems, which are as rough as sandpaper. ‘Lorraine Sunshine’ has cream and green variegated foliage with single yellow flowers. Its seedlings are often true to ‘Lorraine Sunshine’ false sunflower (Heliopsis helianthoides) sports bright yellow flowers and cream and green variegated foliage.

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its parent. ‘Summer Sun’ is floriferous, with semi-double yellow flowers with a darker centre.

CARE: Place in full sun on a variety of soils. Divide every few

years. Deadhead to prevent self-seeding. USE: Use in borders, for massing and as cut flowers.

Daylily (Hemerocallis spp.) The genus name Hemerocallis is derived from the Greek phrase meaning beautiful for a day, a reference to its short-lived flowers (although a mature plant may have several hundred buds and be covered in bloom for two to three weeks). They are not true lilies, which belong to the genus Lilium. Daylilies are long-lived and require little maintenance. A grassy-leafed perennial varying from 0.3 m to 1 m (1–3 ft) or higher, it is available in a wide range of forms and colours. Many of the garden cultivars are derived from two species: the lemon daylily (H. lilioasphodelus, formerly H. flava), which is native to Siberia and northern China and was reportedly once used as an aphrodisiac and the tawny daylily (H. fulva), first introduced into Europe in the 1500s. Native to China and Japan, it has naturalized

The tawny daylily (Hemerocallis fulva), about 1 m (3 ft) high with bright orange flowers, is excellent where the going is tough.

in milder parts of North America through the spread of rhizomes. Both species are rugged and drought tolerant. The lemon daylily is 1 m (3 ft) in height, with fragrant, lemon-yellow, funnel-shaped flowers in May and June. It is one of the first daylilies to bloom and spreads moderately. The tawny daylily is orange with darker interior markings. It is 1 to 1.2 m (3–4 ft) in height and blooms in July and August. H. fulva var. kwanso is a double form. Hundreds of cultivars are available, from the palest yellows to orange, peach, bronze, red, purple and pink. Different cultivars bloom during different periods of the growing season, from spring to late summer. A selection of early-, mid- and lateseason cultivars ensures bloom for most of the summer. Those classified as “dormant” are the hardiest, “evergreen” the least hardy and “semi-evergreen” in between. Modern cultivars are not as aggressive as the species and remain in tighter clumps. ‘Stella D’Oro’ and ‘Happy Returns’ are among those that have repeat bloom, giving them more extended flowering periods. CARE: Daylilies grow in full sun to partial shade (where they

will flower less) in a wide range of soils. They bloom better with even moisture or when mulched, but are drought tolerant once established. They are long-lived, pest- and disease-free and are easily divided and transplanted. USE: They are excellent massed, in perennial or mixed bor-

ders, naturalized, as ground covers or as waterside plantings.

‘Happy Returns’ is among a new group of daylilies (Hemerocallis) with repeat bloom.

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A few cultivars open late in the afternoon and remain open through the night. These are well placed in the “night” garden, with plants that bloom in the evening, especially if they are light in colour or have fragrance. The roots have a crisp, nut-like flavour and may be eaten raw. The flower buds and young leaves are also edible. The flowers are a nectar source for hummingbirds, bees and butterflies.

Coral bells (Heuchera spp.) The genus was named after Johann Heinrich von Heucher (1677– 1747), a German professor of botany. A myriad of tiny pink bells are held on wiry stalks above rosettes of dark green, scalloped leaves, which turn bronze in winter. With the deluge of newer introductions featuring purple, variegated and rust-coloured foliage, some of the hardiest, toughest and best of the older cultivars are no longer widely available and are in danger of being lost. These were created ‘Ribbon Candy’ daylily (Hemerocallis) boasts ruffled petals and a contrasting throat.

when Dr. Henry Marshall of the Agricultural Research Station at Morden, Manitoba crossed the tender, bright red Heuchera sanguinea, which is native to the southwestern United States, with our prairie native, H. richardsonii, a tough plant with nondescript greenish flowers. The cultivars that resulted include the following: ‘Brandon Pink,’ with a height and spread of 50 cm (20 in.), is a deep coral pink. ‘Ruby Mist’ is the same size, with reddish-pink flowers and green foliage with a silver shimmer. ‘Northern Fire’ is a dark scarlet red, 50 to 60 cm (20–24 in.) in height, blooming in June and July. These plants are attractive, hardy, disease-resistant, long blooming and will grace your garden for thirty years or more. The newer purple-leafed, lime-green and amber cultivars are grown mostly for their foliage and are not as hardy, vigorous or drought tolerant as the Morden hybrids. Mostly, they should be treated as annuals or very shortlived perennials. An exception is ‘Stormy Seas,’ which has darker foliage and is more enduring, but not as drought tolerant as the above.

‘Ruby Mist’ is an older variety of coral bells (Heuchera) which is lovely, long flowering, long lived, and very drought tolerant.

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CARE: Plant in full sun on well-drained soils. Divide every three

to four years. USE: Coral bells are excellent as a ground cover, in perennial borders or rock gardens, as edging and as cut flowers.

Bearded iris (Iris spp.) Mostly native to the Mediterranean, iris have graced gardens for centuries. The genus was aptly named for Iris, Greek goddess of the rainbow, whose steps on earth were said to have left these flowers in all colours of the rainbow. Iris bloom for two to three weeks in early June in a wide range of colours, from white through to yellow, pink, peach, blue, purple and maroon. The flowers of bearded iris and Iris germanica hybrids consist of six petals, three upright “standards,” and three down-facing “falls.” The fuzzy growth on the falls is called the beard. The grassy foliage is sword-like and upright, providing interesting form and texture even when the plants are not in bloom. Heights range from 15 to 115 cm (6–45 in.). In terms of hardiness and drought tolerance, not all bearded iris are created equal. There are hundreds of varieties available. Read the fine print on the label to ensure that you are getting what you want. Those classified as “intermediate” and “dwarf” bearded iris are the best choices for the prairies if you’re after longevity and drought tolerance. Generally speaking, the taller bearded iris (those over 1 m/3 ft) are less hardy.

Intermediate bearded iris are the best bet for prairie gardeners in terms of hardiness and flowers. ‘Mrs Andrist’ has graced our gardens for more than a century.

Other species of iris to consider are: I. pseudocorus, the yellow flag iris, whose habitat is usually in or near water, is surprisingly adaptable to dry conditions. Native to Europe and Siberia, it is useful for its foliage alone: the tall (1 m/3 ft), sword-like, blue green clumps resemble cattails. The flowers yield a yellow dye and the seed capsules were once used as a coffee substitute. I. spuria, native to Iran and Turkey, is 60 cm (24 in.) high, with mostly yellow or blue flowers and is saline-tolerant. ‘Protégé’ is one of the most floriferous cultivars. Note: In Alberta, I. pseudocorus is classified as a noxious weed and is illegal to grow. CARE: Bearded iris require full sun and good drainage. Under

shaded conditions, they will not bloom and they soon rot in heavy or soggy soils. Mulch the base of iris prior to their first winter to even out temperature fluctuations and provide a measure of insulation. Divide every four years in July. USE: Iris are excellent in perennial borders, rock gardens,

massed or for edging. The seed capsules are used in dried arrangements. They provide nectar for hummingbirds. ‘Dutch Defiance’ is an outstanding hybrid of Iris spuria.

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Edelweiss (Leontopodium alpinum)

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Edelweiss is less seen in prairie gardens than it once was, possibly because it does not always flourish here, perhaps because of our warm summers or conditions of poor drainage or overwatering. Leontopodium is from the Greek phrase for lion’s foot, which the flower head is supposed to resemble. Alpinum refers to its native habitat, the Swiss Alps. The common name, edelweiss, is the German phrase for noble white, a reference to the star-like bracts. The true flowers are yellow and inconspicuous. Plants are about 15 to 20 cm (6–8 in.) in height with a spread of 30 cm (12 in.). The whiteness of the bracts is affected by growing conditions and genetic variations. The leaves are woolly and attractive. CARE: Grow in full sun (or partial afternoon shade where summers are hot) on well-drained, sandy soil. USE: Use in rock gardens, perennial borders, for edging Edelwiss (Leontopodium alpinum) is an alpine plant grown for its woolly white, star-like bracts.

paths and in dried arrangements.

Blue lyme grass (Leymus arenarius, syn. Elymus arenarius)

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Although a poor choice for the average urban landscape, where space permits, on a farm or acerage, blue lyme grass is striking. Native to the coastal areas of western Europe, where it stabilizes sand dunes, blue lyme grass is excellent as a ground cover for inhospitable, windy spots with excellent drainage. It is grown for both its foliage and flower heads. The genus name, Elymus, is from the Greek word for millet, while the species name, arenarius, means growing in sandy places, a reference to its native habitat. About 60 to 90 cm (24–36 in.) tall, with outstanding, broadly arching, blue-grey foliage, it soon forms a loose, irregular ground cover. The attractive buff flower heads develop into equally attractive seed heads on stems up to 2 m (6 ft) in height and remain through the winter. ‘Blue Danube’ is a slightly more compact selection suitable for containers, in which it will generally overwinter. CARE: Grow in full sun. Given favourable conditions, it spreads

rapidly. Because it is a warm-season grass, it is not slowed by midsummer heat. ‘Blue Danube’ is a smaller and more compact cultivar of blue lyme grass (Leymus arenarius) that has been known to overwinter in containers.

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USE: It is excellent for holding slopes, massed or as a ground cover. Place it in the perennial border only if it can be physically contained. The flower heads are used for drying.

Blazing star, gay feather, dotted blazing star (Liatris spp.) Most species are native to North America, but only one droughttolerant species is commonly found on the Canadian prairies, dotted blazing star (Liatris punctata), which is best purchased at a specialized native plant nursery. L. spicata, native to the central and eastern United States and moderately drought tolerant, is readily available at garden centres, as are its cultivars, but it tends to be rather short-lived in our prairie gardens, although it seeds freely. Rosy-purple flowers bloom in bottlebrush-like spikes in late summer above a mound of grass-like foliage with a height and spread of 80 by 40 cm (32 x 16 in.). They are unusual in the flower world in that the florets in the spikes begin blooming at the top and work their way down. Among the L. spicta hybrids are: ‘Alba’ which is white. Floristan series has white or violet flowers. ‘Kobold’ is compact with mauve flowers. CARE: Plant in full sun on well-drained soil. USE: Place in borders, containers and use as cut flowers; they attract butterflies.

Sea lavender, statice (Limonium spp.)

Dotted blazing star (Liatris punctata), a prairie plant, is best purchased at a specialized native plant nursery.

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An airy plant with tiny flowers on finely branched stems, sea lavender is similar to the now largely banned baby’s breath but is even more attractive. It is long-lived and deep-rooted. The genus name, Limonium, is from the Greek word leimon, a meadow, the plant’s native habitat. Common or wide-leaf sea lavender (Limonium latifolium) is native to the coastal salt marshes of Europe and Asia. It has billowy sprays of tiny, lavender-blue flowers on 60 to 90 cm (24–36 in.) stems from July until hard frost. The flowers are held above rosettes of long, dark green leaves. ‘Elegance’ has deep blue flowers. ‘Violetta’ has deep violet flowers. German or Tartarian sea lavender (formerly L. tataricum, now Goniolimon tartaricum) blooms in July and August and is a bit shorter, with a height and spread of 40 cm (16 in.). It has somewhat stiffer flower stalks, producing triangular, flattopped sprays of silver grey flowers.

Blazing star (Liatris spp.) is unusual in the plant world in that the florets begin blooming at the top.

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L. tataricum var. angustifolium (formerly L. dumosum) has silver-lavender flowers. L. tataricum var. nanum has fluffy pink flowers and is only 24 cm (9 in.) high. CARE: Plant sea lavender in full sun in a loamy but well-drained

soil. It is drought tolerant once established. Clumps resent disturbance, transplanting or division once established and may die as a result. USE: Excellent as border plants, they have long been used in both fresh and dried arrangements.

Perennial flax (Linum perenne)

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We’re all familiar with the great stretches of blue that almost If you may no longer grow baby’s breath where you live, try sea lavender or statice (Limonium spp.). You won’t be disappointed.

seem to reflect the sky when flax fields (Linum usitatissimum) are in flower on the prairies. This garden perennial is in the same genus. Linum is the Latin name for flax, while perenne means perennial. The common name is derived from the Dutch flas and the German flacks, meaning to flay, part of the processing of flax. Native to Europe, flax has been grown since ancient times as a source of linen, rope and linseed oil. Plants are about 60 cm (24 in.) in height, with tiny, narrow leaves and 2.5 cm (1 in.), sky blue flowers. The overall appearance of the upright, arching clumps is light and airy. Individual flowers last only a day, but plants bloom over a four- to sixweek period beginning in late spring. Flowers close on cloudy, dull days. ‘Album’ is similar to the species but with white flowers. ‘Diamond’ is shorter, with a height and spread of 25 by 30 cm (10 x 12 in.) and white flowers. ‘Sapphire’ is similar in size, with sapphire-blue blooms on a dwarf, well-branched plant. L. lewisii is native to the prairies with slightly smaller flowers. CARE: Plant in full sun on well-drained soil. The plants have a

woody base and resent disturbance once established. They do not usually survive division or transplanting. Although shortlived (three or four years), they do reseed. Shear lightly after flowering for a neater appearance and perhaps to encourage a second flush of bloom. Perennial flax (Linum perenne), easily grown from seed, is light and airy and available in blue or white flowers.

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USE: Flax is used in perennial borders, cottage gardens and for massing or naturalizing in drier areas.

Birdsfoot trefoil (Lotus corniculatus ‘Plenus’)

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Native to the grasslands of Eurasia and North Africa, birdsfoot trefoil is a member of the legume family. Originally used as an agricultural forage plant and invasive in some parts of the world, the double form has come into its own as a droughttolerant ground cover. Low and spreading, it is 8 to 10 cm (3–4 in.) in height. The double flowers are golden-yellow with red specks and bloom in June and July. The flowers are pea-like in form and later develop into pods. The leaves are compound, each with five leaflets. Plants are poisonous if ingested. CARE: Place in full sun on various soils. USE: Useful as a ground cover and to hold slopes; they are too invasive for a border.

Rose campion (Lychnis coronaria, syn. Silene coronaria) The contrast between the soft grey foliage and the bright magen-

Birdsfoot trefoil (Lotus corniculatus ‘Plenus’) is an excellent ground cover for inhospitable places.

ta flowers of the rose campion is stunning. It’s a perennial that garden visitors ask about. Lychnis is from the Greek word for lamp and alludes to the bright flowers, while coronaria means used in garlands, something the Greeks were fond of. Plants are native to southern Europe. The simple, oblong leaves are about 10 cm (4 in.) long, opposite and form a silvery rosette. Their velvety texture invites petting. The flowers are 5 cm (2 in.) in diameter and a vivid magenta. Plants are about 60 cm (24 in.) in height. ‘Alba’ is a white form. ‘Angel’s Breath’ has white petals and a soft pink centre. ‘Gardener’s World’ is very different in that flowers resemble bright red carnations, blooming for six weeks. Place in a protected location in colder areas of the prairies. CARE: Plant in full sun to light shade on well-drained soil. They

are vulnerable to crown rot during spring thaw and should be bermed in low areas or in heavy soil. Regarded as short-lived perennials, they do reseed, so refrain from mulching. USE: Use in informal cottage gardens, borders and as cut flowers. The bright magenta flowers against the soft grey foliage make rose campion (Lychnis coronaria) truly stunning.

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Malva, musk mallow (Malva spp.) We may think of them as a shorter, perhaps boxier cousin to the hollyhock, but mallows are also closely related to hibiscus. Along with several species, many new cultivars have been introduced in the last decade. They bloom in midsummer. The genus name, Malva, is derived from the Greek malakos, meaning to soften. An extract from the sap was once used to soften and soothe the skin. Hollyhock mallow (Malva alcea) is 1 to 1.2 m (3–4 ft) in height and produces 5 cm (2 in.) rose or white flowers for six to eight weeks. It is short-lived. Musk mallow (M. moschata) is native to Europe, with very showy, satiny, rose-coloured flowers on somewhat sprawling plants, 60 to 90 cm (24–36 in.) in height. Moschata means musky and describes the aromatic, deeply cut leaves. ‘Alba’ is a white-flowered form. Although short-lived, Musk mallow (Malva spp.) is related to hollyhock and is equally attractive. It is a nectar plant for butterflies.

plants are long-blooming and self-seed reliably. ‘Appleblossom Pink,’ is 45 to 70 cm (18–30 in.) in height. ‘Pink Perfection,’ with a height and spread of 90 cm (36 in.), is pink, blooming in mid to late summer. ‘Rosea’ has pink flowers above deep green foliage, 60 to 90 cm (24–36 in.) in height. ‘White Perfection,’ with a height and spread of 70 cm (28 in.) has white flowers on sturdy stems. High mallow (M. sylvestris) has many cultivars. Allow the plants to self-seed. ‘Braveheart’ is a bright mauve with a purple eye and is 1.2 to 1.5 m (4–5 ft) in height. ‘Zabrina’ has pink or white flowers with purple veins on strong stems and is 1 m (3 ft) in height. CARE: Plant in full sun or partial shade on well-drained soils.

Like hollyhocks, mallows are subject to foliage rust. USE: These plants are well suited to borders, cottage gardens,

naturalizing or concealing unsightly objects. Use as cut flowers. They are a nectar plant for butterflies.

Catmint (Nepeta spp.) ‘Dropmore Blue’ is one of the best catmints (Nepeta spp.).

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Nepeta is the Latin word for mint. Like other members of the mint family, catmint is characterized by square stems and opposite

leaves. The foliage is generally a grey green and emits a fragrance when crushed. Flowers can be blue, purple, mauve-pink or white. N. sibirica ‘Blue Beauty’ (introduced as ‘Souvenir d’Andre Chaudron’ by Skinner’s Nursery in 1948) is about 60 cm (24 in.) tall.

Cats and catnip What is it that causes some cats to go crazy after eating catnip, chewing, licking, rolling around, pawing and purring in ecstasy? Why do they growl, meow or salivate as

N. grandiflora ‘Dawn to Dusk’ form large plants up to 90 cm (36 in.) in height, with pink flowers. It has not been widely tested on the prairies, so place it in a protected location. ‘Dropmore Blue’ is a cross of Nepeta mussinii and N. ucranica introduced by Dr. Frank Skinner of Dropmore, Manitoba in 1932. It is compact, 30 to 38 cm (12–15 in.) in height, with soft, scalloped, grey green leaves and light purple flowers. Because it is sterile, it blooms almost the entire summer and does not reseed, nor is it invasive. It is used extensively in English rose gardens as edging. ‘Six Hills Giant’ is 1 m (3 ft) in height, with dark blue flowers above grey foliage. It has not been widely tested but is

though on a drug-induced high? A chemical compound within the plant tissue may mimic the sexual or territorial pheromones (a sort of feline “perfume”) of the cats themselves. The active ingredient, nepetalactone, an aromatic oil, is detected through the cat’s olfactory system, by what is known as Jacobson’s organ at the back of its nose. It must be inhaled to be effective. Although dramatic, the cat’s response is generally limited to ten or fifteen minutes, but may repeat itself after a few hours’ lapse. Catnip has no harmful or long-term effects on cats and some may become indif-

worthy of trial. ‘Walker’s Low’ (N. racemosa) is named for a village, not its height, which is 40 cm (16 in.), with a spread of 60 cm (24 in.), making it a bit larger than ‘Dropmore Blue.’ It has purplishblue flowers throughout the summer.

ferent due to overexposure – by which time your plant may be dead. Response to catnip is hereditary, so not all cats succumb. Most Australian cats (derived from a rather small gene pool due to many

CARE: Plant in full sun or partial shade on well-drained soil.

years of strict quarantine) are indifferent to

Shear after flowering for a neater appearance. All do better on a leaner soil.

it. Most kittens do not develop a response until at least three months of age. Older cats also appear less interested.

USE: ’Dropmore Blue’ is excellent as a border plant, as a

Urban cats seem more interested than

companion to roses (for which it is used extensively in Great Britain), for edging, massing and as a cut flower. It is a nectar source for bees. More aggressive catmints are best used for massing, naturalizing, in cottage gardens or for stabilizing slopes. If you don’t like cats, give a plant to your neighbour.

rural cats, perhaps because rural cats have

Missouri evening primrose

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better things to do with their time. They prefer stalking prey with fur or feathers. City cats have fewer options, more restrictions and go for the catnip. How can gardeners prevent neighbourhood cats from digging up or destroying their catnip? Wire barriers and baskets may

(Oenothera missouriensis, syn. O. macrocarpa)

do the job, but do little to enhance the

Evening primrose should not be confused with the true prim-

beauty of one’s flower borders. Inserting

rose, Primula. These two unrelated genera share only a common

thorny sticks (such as rose, sea buckthorn or

name. Missouri evening primrose produces pale yellow flow-

raspberry canes) among the stems may be

ers of up to 12 cm (5 in.); though they look delicate, almost like

a less obvious but equally effective way of

tissue paper, the flowers persist for many days and are borne

deterring unwanted felines.

from midsummer onward. The stems are about 45 cm (18 in.) in height, often trailing or sprawling before turning upright as flower stems. It has deep, woody roots.

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White evening primrose (Oenothera nutallii) is a lovely native evening primrose with very fine, needle-like leaves. Four-angled primrose (O. tetragona) is native to Nova Scotia. Red buds open to lemon-yellow flowers. In colder areas of the prairies, plant in a protected location. ‘Illumination’ is more upright, with larger flowers and is better suited to a border, but it may not be as longlived and will need protection in the colder areas of the prairies. CARE: Plant in full sun on well-drained soil. They will not do well otherwise. USE: Use for naturalizing and cottage gardens. The decorative, winged seed pods are used in dried arrangements. The seeds are eaten by several species of birds.

Missouri evening primrose (Oenothera missouriensis) has soft yellow flowers with a delicate tissue paper appearance in midsummer.

Prickly pear cactus (Opuntia polyacantha)

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The flowers are lovely, but then there are the spines. It is, after all, a cactus. The fruit of this native cactus is a straw-coloured, edible berry, but one would have to be pretty desperate to brave the spines in order to harvest it. The species name, polyacantha, means many spined. The stems are succulent and pear-shaped. The leaves have been modified to clusters of grey spines evenly distributed over the stems. The plant is 13 cm (5 in.) in height and produces waxy, lemon-yellow flowers, 5 to 7.5 cm (2–3 in.) in diameter, in June and July. CARE: Plant in full sun on very well-drained, sandy soils. USE: Cacti are useful in the hottest, driest areas of rock gardens, especially those that are inaccessible to small children, unsuspecting garden guests and pets.

Peony (Paeonia spp.)

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Peonies have graced prairie gardens almost since European settlement began. You can still see them in full flower on long-abandoned homesteads where no one has looked after them in decades. The peony was named to honour the mythical Greek physiPrickly pear cactus (Opuntia polyacantha) are best placed in the hottest, driest area of a rock garden, inaccessible to small children, unsuspecting garden guests, and pets.

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cian to the gods, Paion. Most cultivars are hybrids of the Chinese peony, P. lactiflora, native to Siberia and northern China. Noted for their longevity and low maintenance, they have attractive flowers and handsome, glossy green foliage. There are hundreds of varieties to choose from. Flowers are white, yellow,

pink, red or purple, with single to fully double forms. Plants range from 60 to 90 cm (24–36 in.) in height. Many are fragrant. Allow about four years for the plant to display its mature flower and leaf forms – juvenile foliage may not be as deeply divided as older plants of the same cultivar, nor will the doubleness of flowers be stabilized. Single and Japanese forms are lovely in their simplicity. The flowers weigh less and they have no need for supportive hoops. As well, modern breeding has concentrated on stronger stems, so these types are less likely to be blown into the mud at the first sign of wind or rain. Among these are ‘Claire de Lune,’ ‘Flame,’ ‘Bowl of Beauty,’ ‘Jan van Leeuwen,’ ‘Do Tell,’ ‘Requiem’ and ‘Sea Shell.’ There are many more. The tree peony (Paeonia suffruticosa) is not reliably hardy in the colder regions of the prairies but does well in southern Manitoba and in protected locations elsewhere. The fern-leaf peony (P. tenuifolia) is hardy but requires more even moisture. The Itoh intersectional hybrids such as ‘Bartzella,’ ‘Cora Louise’ and ‘Morning Lilac’ have done well in the Calgary area and elsewhere, but their drought tolerance is yet to be determined.

‘Requiem’ is a pure white single peony (Paeonia lactiflora) with strong stems that do not need a hoop for support.

CARE: Plant in deep, well-drained soil. Older cultivars with

large, double flowers and relatively weak stems may need support in the form of wire hoops. Ensure that buds on root divisions or newly acquired peonies are placed no lower than 5 cm (2 in.) below the soil surface; deep planting inhibits and delays flowering. It is better to plant too shallowly and mulch with dried leaves for the first winter than to plant too deeply. Keep plants moderately moist during their first few years. Once established, they are extremely drought tolerant. USE: Peonies are valuable in perennial and mixed borders,

either singly or massed and as cut flowers.

Oriental poppy (Papaver orientale)

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The common name, poppy, is from the Anglo-Saxon word for sleep, a reference to the narcotic properties of a different species. Oriental poppies are native to the Caucasus, Iran and Turkey and both the species and common names allude to the Orient. The species is 60 to 75 cm (24–30 in.) in height, with bright scarlet flowers in May and June. There is a prominent purple-black blotch at the base of each petal. Many cultivars exist, with flowers of pink, salmon, white, orange, red or purple, both single and double. The satiny flowers are large, up to 12 to 15 cm (5–6 in.) in diameter.

‘Bowl of Beauty’ (P. lactiflora) has large pink single flowers with a creamy white centre and will not need a support hoop.

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The leaves are hairy, deeply lobed and sharply toothed. Roots are deep, fleshy and brittle. Some varieties are grown as seed strains and individual plants will show variation; others are vegetatively propagated by division, cuttings or tissue culture and will be identical. ‘Allegro,’ with a height and spread of 60 by 30 cm (24 x 12 in.), is a dwarf orange selection propagated by seed. ‘Beauty of Livermore’ (100 x 30 cm/40 x 12 in.) is dark red and propagated by seed. ‘Brilliant’ (75 x 100 cm/30 x 40 in.) is a fiery scarlet with a black centre, propagated by seed. ‘Double Pleasure’ (100 x 75 cm/40 x 30 in.) has double salmonpink flowers with a purple basal blotch. ‘Perry’s White’ is white with a maroon-black centre. ‘Picotee’ has creamy-white flowers with a unique orange ruffled edge. ‘Princess Victoria Louise’ is a soft salmon-pink with a dark centre (seed). ‘Double Pleasure’ oriental poppy (Papaver orientale) has double salmon-pink flowers with a purple basal blotch.

‘Queen Alexander’ (80 x 30 cm/32 x 12 in.) is pink with a black centre. ‘Raspberry Queen’ has double, fringed, raspberry-pink flowers with a black centre. ‘Royal Wedding’ (80 x 30 cm/32 x 12 in.) is white with a black centre (seed). ‘Turkenlois’ is bright scarlet-orange with fringed petals. CARE: Plant in full sun and well-drained soil. They go dormant

in August, forming new rosettes of basal leaves by September, when they can be divided. They are often planted in narrow diagonal drifts surrounded by later-blooming plants that hide their dying foliage after they finish blooming. USE: While in bloom oriental poppies make an enormous visual impact in perennial borders and as cut flowers. The decorative seed pods are used in dried arrangements.

Beardtongue (Penstemon spp.) ‘Picotee’ is a unique oriental poppy (P. orientale) with creamy-white flowers and an orange ruffled edge.

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All of these species are native to North America. The common name, beardtongue, as well as the species name, barbatus, describes the short, bristly hairs on the lower lip, which descend into the throat of the flower. The genus name is from the Greek words pente,

five and stemon, stamen, referring to the five stamens in the flower. Among our native penstemons, the ones that have most successfully made the journey to cultivated gardens have been smooth beardtongue (Penstemon nitidus), a short-lived perennial that perpetuates itself through self-seeding and slender beardtongue (P. procurus). P. nitidus is the more drought tolerant of these, although P. procurus appears more adaptable to gardens, forming nice mats of foliage. It also has variety in terms of flower colour and height. Common beardtongue (P. barbatus) hybrids are equally shortlived (the species is native to the southwestern United States) but much more widely available at garden centres. As gardeners, our best bet is to treat them as annuals (or very short-lived perennials) and place them where they can easily reseed. The tubular, lipped flowers are in spikes held above the low mounds of foliage, 30 to 45 cm (12–18 in.) in height. They bloom from mid to late summer. Colours include white, pink, purple and blue. ‘Dark Towers’ has dusky foliage and pink flowers.

‘Dark Towers’ beardtongue (Penstemon barbatus) has dusky foliage and pink flowers.

‘Prairie Dusk’ is purple with strong stems. Penstemon x mexicali ‘Red Rocks’ should be treated as a self-seeding annual but is worth growing for its pink flowers and glossy foliage. CARE: Good drainage is critical when it comes to penstemons. Plant in full sun in well-drained soil. Allow them to reseed. USE: Place in borders, rock gardens, as edging and use as cut flowers.

Russian sage (Perovskia atriplicifolia)

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Although its origin is geographically close to Russia and it is distantly related to sage, Russian sage is neither from Russia nor is it a sage. Native from Afghanistan to Tibet, it is a member of the mint family and the crushed or bruised leaves release a sagelike fragrance. It was named after V. A. Perovsky (1794–1857) a statesman and military officer. I first came across Russian sage years ago in Minnesota and promptly fell in love with it. When it eventually made its way into the Canadian horticultural market I immediately purchased one, but it never appeared the following spring in my then exposed-to-the-winds borders. Several friends in more protected urban areas have fared well with it and I think I’ll try it again now that my trees have grown.

Smooth beardtongue (P. nitidus), a native prairie plant, is a shortlived perennial that perpetuates itself through reseeding.

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Tiny two-lipped, light blue flowers are produced in airy panicles around the stems in mid to late summer. The overall impression is of a shrub-like baby’s breath with multiple narrow stems rising to 1 m (3 ft). CARE: Plant in full sun in well-drained soil. In colder or exposed

areas, place it in a protected location. Leave the foliage through the winter. When removing old growth in the spring, it’s critical to leave about 15 to 30 cm (6–12 in.) of stem from which basil buds will arise for the coming year’s growth. USE: Plant Russian sage towards the back of a perennial or

mixed border, mass it with similar perennials blooming at about the same time (such as coneflowers) and use it as a cut flower.

Fleeceflower, knotweed (Persicaria spp.) Common names can be misleading. Although fleeceflower is a member of the same genus as the knotweed in our lawns, the similarity stops there. Russian sage (Perovskia atriplicifolia) does best in full sun on well drained soil.

Dwarf or Himalayan fleeceflower (P. affinis, syn. Bistorta affinis) forms a low mat of leathery leaves covered with rose-red flowers. ‘Dimity,’ with a height and spread of 20 by 30 cm (8 x 12 in.), is a more vigorous selection. The pink flowers turn crimson as they age, giving the clump an interesting two-tone effect. Fleeceflower or knotweed (Persicaria bistorta ‘Superba,’ syn. Polygonum bistorta ‘Superbum’, Bistorta officinalis) is native to Europe and Asia. Polygonum (the older botanical name) means many-jointed knees, referring to the stems. Bistorta means twisted and describes the roots, which are very thick. Fleeceflower is 45 to 75 cm (18–30 in.) in height, with dense spikes of pink flowers resembling bottle brushes in mid to late summer, which are held well above the foliage. The distinctive basal leaves are 10 to 15 cm (4–6 in.) long, with wavy margins and a white midrib. The cultivar ‘Superbum,’ meaning superior, has larger flowers than the species. CARE: Grow in sun or partial shade on well-drained soil.

Fleeceflower (Persicaria bistorta ‘Superbum’) produces dense pink bottlebrush flowers in mid to late summer.

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USE: Fleeceflower is excellent in perennial borders, massed, used as a ground cover and as a cut flower. It has been used to skirt a large spruce tree in the Calgary Zoo gardens.

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White or giant fleeceflower (P. polymorpha)

is native

to China, Korea and Japan and was introduced to North America by German-American landscape architect Wolfgang Oehme. In spite of its enormous size, it is clump-forming and non-invasive. It looks like a large shrub and the flowers are reminiscent of a Japanese tree lilac. I was introduced to it by a friend and excellent gardener in Dawson Creek, British Columbia and carried a bit back home in my hand luggage. It has been a part of my landscape ever since and always incites positive comment. Forming a strong upright clump with a height and spread of 2 m (6 ft) or more, it has large white flowers that begin blooming in July and continue through the end of August. CARE: Place in full sun. It is adaptable to various soils. USE: Use in borders and as a specimen plant.

Tunic flower (Petrorhagia saxifraga) Native to southern Europe, Asia Minor and Iran, the tunic flower

Giant fleeceflower (P. polymorpha) is hardy, drought tolerant and a giant of a perennial with a height and spread of 2 m (6 ft) or more.

is an unusual, little-used perennial that resembles a more open, dwarf baby’s breath. Slightly cupped pink or white flowers rise about 30 cm (12 in.) above a loose cushion of green foliage for a long period over the summer. The cultivars vary from white to dark pink, single and double, but may be difficult to source. ‘Alba’ is a white form. CARE: Plant in full sun in well-drained soil. They may self-seed. USE: Use in rock gardens or cottage gardens.

Ribbon grass (Phalaris arundinacea var. picta)

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It’s lovely to look at but will need to be contained. Native to Europe and North America, ribbon grass is 60 to 120 cm (24–48 in.) in height, with variegated green-and-white leaves forming loose, upright clumps. ‘Feesey’ (‘Strawberries & Cream’) is similar to the species but with a pink tinge in spring and fall. CARE: It will tolerate a variety of soils in full sun to partial shade.

Under favourable conditions, it spreads quickly by rhizomes. It is a cool-season grass and its growth is curtailed during the heat of midsummer. Mowing at that time improves its appearance and stimulates growth in early fall.

Not often seen in our prairie gardens, tunic flower (Petrorhagia saxifraga) may be difficult to find, but is worth the search.

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USE: It is excellent massed, naturalized, as a ground cover or in containers, but is too aggressive for the perennial border.

Jerusalem sage (Phlomis tuberosa ‘Amazone’) This is an unusual, easy, low-maintenance, sturdy but sadly underused drought-tolerant perennial. ‘Amazone’ was selected in Germany and should be much more widely available to prairie gardeners. Whorls of two-lipped, mauve-and-pink, tubular flowers are held in successive tiers around long, burgundy stems from mid to late summer. The somewhat woolly, heart-shaped, grey-green leaves have wavy margins and form low mounds of foliage with a height and spread of about 90 by 60 cm (36 x 24 in.). CARE: Place in full sun and well-drained soil. USE: Use in borders and as cut flowers. Ribbon grass (Phalaris arundinacea var. picta) is an attractive green and white variegated ornamental grass.

Phlox (Phlox spp.)

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Spring on the prairies would not be the same without carpets of phlox in bloom. Phlox is Greek for flame and describes the bright pink flowers. Garden cultivars of phlox are usually hybrids of two or more species. Many of these species were introduced to England from North America by plant explorer John Bartram in the 1740s. Within two centuries, hybrids developed in Europe had made their way back to North American gardens through the nursery trades. Arctic phlox (P. borealis) is native to Alaska and Canada, hence the species name, borealis, indicating its northern origins. It forms a low mound, about 10 cm (4 in.) in height, of narrow, needle-like, evergreen foliage. The small pink, white, lilac or lavender flowers bloom in May. The stems are woody. Douglas moss phlox (P. douglasii) is 10 cm (4 in.) in height and is denser than the other species and hardy to -40°. ‘Crackerjack’ is a bright magenta red. ‘Rose Cushion’ is a soft pink. Moss or creeping phlox (P. subulata) is native to the eastern United States. Subulata means awl-shaped and describes

Jerusalem sage (Phlomis tuberosa) has whorls of twolipped mauve and pink flowers in tiers around the stem.

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the leaves. It is similar to P. borealis, but with a height and spread of 15 by 30 cm (6 x 12 in.) and available in a much greater colour range. It is also not as hardy, vigorous or

long-lived in the colder areas of the prairies. Blues are the least dependable. ‘Amazing Grace’ is white with a mauve edge. ‘Autumn Rose’ is pink. ‘Candy Stripes’ has rose-pink flowers edged in white with a crimson eye. ‘Crimson Beauty’ is a bright rosy red. ‘Ellie B,’ a white selection, is especially hardy and attractive. ‘Emerald Blue’ is blue. ‘Emerald Pink’ has soft pink flowers. ‘Rubies Choice,’ a bright pink, is especially hardy and attractive. ‘Scarlet Flame’ is red.

‘Emerald Pink’ is a cultivar of moss or creeping phlox (Phlox subulata).

‘White Delight’ has white flowers. CARE: Plant in full sun or partial shade with good drainage. In exposed sites, winter desiccation may occur. Shear after flowering to promote vigorous growth. Divide every three years. USE: Phlox are excellent in rock gardens or perennial borders, as ground covers, edging paths, among paving stones, trailing over low walls and nestled in garden steps.

Potentilla (Potentilla spp.)

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Gardeners are usually more familiar with the woody, shrubby potentillas than the herbaceous forms. Although the herbaceous forms are not as readily available as the shrubs, they are of great value in our landscapes in borders and as ground covers. Potentilla comes from the word potens, powerful and refers to its reputed medicinal and magical properties. All have five-petalled, buttercup-like flowers. Silverweed (P. anserina) is native to the prairies and forms a thick mat of silver-green foliage only 15 cm (6 in.) high, with 2.5 cm (1 in.) yellow flowers in May and June. Orangespot cinquefoil (P. crantzii, syn. P. alpestre), native to Europe and Asia, has bright yellow flowers in June and July and a height of 30 to 38 cm (12–15 in.). It reseeds with gusto and can be weedy. It’s good for naturalizing in difficult situations.

‘Ellie B.’, a white selection of moss phlox (P. subulata), is especially hardy and attractive.

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Woolly cinquefoil (P. megalantha, syn. P. fragiformis, P. emar-

ginata) is one that invites petting. Native to Asia and the Altai Mountains through to Alaska, the plants are tufted and compact, with a height and spread of 35 by 45 cm (14 x 18 in.) and grey-green, felt-like foliage. The yellow flowers bloom in late spring and are suited to rock gardens and the front of the border. ’Miss Willmott’ (P. napalensis), with a height and spread of 30 cm (12 in.), has pink flowers with a darker centre in midsummer. It is best planted in a protected location in colder regions of the prairies. ’Monarch’s Velvet’ (P. thurberi) with deep ruby-red flowers is hardy to zone 4. Plant in a protected location elsewhere. Three-toothed cinquefoil (P. tridentata) has tiny white flowers in late spring above a mat of trifoliate leaves, each leaflet Silverweed (Potentilla anserina) is a native plant with a thick mat of silver-grey foliage and yellow flowers in May and June.

with three teeth. Native to the boreal forest regions of the prairies, it is available from specialist native plant nurseries. CARE: Potentillas do well in full sun on well-drained soils. USE: Ideal as ground covers on hot, dry slopes, potentillas also fit in rock gardens.

European pasque flower (Pulsatilla vulgaris, syn. Anemone pulsatilla)

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As prairie dwellers ritualistically seek out the prairie crocus each spring to assure themselves that winter is indeed over, so plant lovers in Europe go trooping after the common pasque flower with the same hopes. Very similar to our native prairie crocus (Anemone patens), this European species has larger flowers with brighter, more intense colours. More importantly, it is much better adapted to a cultivated garden environment. Large fuzzy buds precede the purple, red, pink or white flowers, which are in turn followed by attractive, silky seed heads over low plants with a height and spread of 15 by 20 cm (6 x 8 in.). ‘Alba’ is a clear white. ‘Papageno’ has fringed petals in unusual colours. ‘Rubra’ is a showy red. CARE: Plant in full sun and well-drained soil. The pasque flower (Pulsatilla vulgaris) is the European equivalent to the prairie crocus – a harbinger of spring.

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USE: Use in rock gardens or the front of the border.

Prairie coneflower (Ratibida columnifera)

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This is the “other” coneflower (Echinacea shares the same common name but is more used as a garden flower), found blooming alongside our roadsides in late summer. A prairie native, it is considered a short-lived perennial or a biennial. The medium-sized plants have a height and spread of about 90 by 60 cm (36 x 24 in.) and are finely branched. The flowers, blooming in August and September, are distinguished by their mostly yellow, drooping ray petals that surround a high, dark green central cone. ‘Mexican Hat’ (R. columnifera var. pulcherrima), in spite of its name, is native to the prairies but quite rare. Its drooping petals are red. CARE: Think of where they grow naturally – gravelly road-

sides – and keep them lean and mean to prevent floppiness. Place them in an unmulched bed so they can self-seed freely. Plant in full sun in well-drained soil. USE: Use in borders, cottage gardens, as cut flowers and for

naturalizing.

‘Mexican Hat’ is an unusual form of the prairie coneflower (Ratibida columnifera).

Rudbeckia (Rudbeckia spp.) Native to North America, the genus is characterized by yellow petals (the ray flowers) surrounded by a raised brown-to-black cone. It includes annuals, biennials and perennials. ’Goldstrum’ rudbeckia (Rudbeckia fulgida var. sullivantii ‘Goldstrum’), an award-winning perennial plant of the year, forms an upright, compact, bushy clump of 60 to 75 cm (24–30 in.). Blooming from midsummer to fall, the single, goldenorange petals surround a brown centre. It’s a real knockout but may be short-lived in colder regions of the prairies. Goldenglow (R. laciniata ‘Hortensia’).

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lane in an older prairie neighbourhood in mid to late summer and you’re likely to come across this plant not only in bloom but with a gracious gardener willing to share a piece of it. This older cultivar is hardy, long-lived and extremely drought tolerant. Native to North America, it was found by J. L. Child (thought to be a botanical artist) and listed in Bailey’s Cyclopedia of American Horticulture by 1894. Although tall (about 2 m/6 ft), the stems are sturdy (unless overwatered or overfertilized) and do not require staking. The large (5–9 cm/2–3.5 in.), double, golden-yellow flowers are held above large clumps of deeply lobed foliage. It is a vigorous perennial.

‘Goldstrum’ rudbeckia (Rudbeckia fulgida var. sullivantii) is a real knockout but may be short-lived in colder regions.

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CARE: Plant in full sun and well-drained soil. Deadhead

‘Goldstrum’ for more continuous bloom. USE: Use in borders, massed, for naturalizing and as cut flowers.

They are attractive to butterflies.

Salvia ‘Superba’ (Salvia x ‘Superba’) Although relatively short-lived on the prairies, salvias, with their rich, deep colours, are certainly worth the effort of replanting every three or four years. Salvus is Latin for safe or healthy, a reference to the plant’s ancient medicinal uses. A member of the mint family, it has dense spikes of tubular, two-lipped flowers above grey-green foliage. Long-flowering and trouble-free, these plants bloom from late spring through early summer. They are mostly hybrids of S. nemorosa and other species native to Turkey, Iran and Afghanistan. ‘May Night’ salvia (Salvia x ‘Superba’) is excellent in borders, and attracts butterflies.

‘Blue Hill’ (45–60 cm/18–24 in.) is a true blue. ‘Blue Queen’ is 45 to 60 cm (18–24 in.) in height with rich violet flowers. ‘Caradonna’ has deep violet-blue flowers on blue-black stems of 50 to 75 cm (20–30 in.). ‘East Friesland’ is a deep violet-purple of 45 cm (18 in.). ‘May Night’ (45 cm/18 in.) has larger violet-blue flowers. ‘Rose Queen’ (60 cm/24 in.) has rosy-pink flowers. CARE: Grow in full sun in ordinary, well-drained soil. Shear

after flowering for a neater appearance and possible rebloom. USE: Excellent in borders, massed, as specimen plants and for cut flowers, they also attract butterflies.

Rock soapwort (Saponaria ocymoides) The genus name is from the Latin sapo, meaning soap and the bruised leaves will indeed produce a lather. Ocymoides means resembling basil, alluding to the leaves. A member of the pink or carnation family, it has star-shaped flowers in loose sprays that range from pink to white, and blooms in late spring and early summer. Only 10 to 20 cm (4–8 in.) in height, it is a vigorous, trailing plant, native to the European Alps. Let rock soapwort (Saponaria ocymoides) trail over low walls or place it in the rock garden.

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CARE: Plant in full sun in well-drained soil. Shear after flowering

for a neater appearance. It is drought tolerant when established.

USE: Good for trailing over low walls, on slopes and in rock gardens.

Pincushion flower, scabious (Scabiosa caucasica)

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While the S. columbaria hybrids have not been as hardy, longlived or drought tolerant in my experience, I’ve found this species, which is native to the Caucasus Mountains, much more drought tolerant than it is generally given credit for. The genus is from the Latin word for itch, as the leaves were once believed to cure scabies and other skin problems. The common name is derived from the resemblance of the stamens in the centre of the flower to a pincushion. The lacy flowers, in blue, white or pink, are 2 to 3 cm (about 1 in.) in diameter and appear in late summer above grey-green, lance-like foliage. Plants are 30 to 60 cm (12–24 in.) in height. ‘Alba’ is white. ‘Pink Lemonade’ (S. columbaria) has pink flowers and variegated foliage. It may not be hardy in colder regions of the prairies. CARE: Plant in full sun. Deadhead for more continuous flowering.

Pincushion flower or scabious (Scabiosa caucasica) is a lovely perennial and was once used to cure scabies and other skin problems.

USE: Use in borders and for cut flowers.

Stonecrop (Sedum spp.)

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More and more sedums appear every year, each one with more charm and variation of form and colour than the previous. Many cultivars seem very similar and there is some confusion about nomenclature. With some truth, my son used to comment, “You sedum one, you sedum all,” yet their charming distinctions remain. The genus name is from the Latin word sedo, to sit and alludes to the way in which these plants sit on walls and rocks. A large group of mostly low (15–30 cm/6–12 in.), succulent perennials, sedums are valued as much for their foliage as for their flowers. The following cultivars are among those recommended for the prairies. ‘Autumn Joy’ (syn. Hylotelephinium spectabile), is a hybrid of S. telephinum and S. spectabile, 60 cm (24 in.) in height, with pink flowers in late August or early fall. Dragon’s blood (S. spurium), with pink flowers and a low spreading habit, has a number of attractive cultivars: ‘Bronze Carpet’ with bronze foliage, ‘Roseum’ with pink flowers and ‘Tricolor’ with variegated leaves (which may be less hardy).

Dragon’s blood sedum (Sedum spurium) is dependably hardy given full sun and good drainage.

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Ewer’s stonecrop (S. ewersii) has blue-grey foliage and pink flowers in July. Evergreen stonecrop (S. hybridum) has glossy green leaves and yellow flowers in early summer. Goldust stonecrop (S. acre) is only 8 cm (3 in.) tall, with masses of tiny leaves and tiny yellow flowers in late spring. It’s a spreader. S. kamtschaticum, with yellow flowers, is 15 to 20 cm (6–8 in.) in height. S. kamtschaticum ’Middendorffianum’ forms a clump of dark green leaves with yellow flowers. S. kamtschaticum ’Variegatum’ has attractive, green and white variegated leaves. ‘Autumn Joy’ (syn. Hylotelephinium spectabile), is a hybrid sedum that is dependably hardy and puts of a great show from late August to hard frost with pink flowers on 60 cm (24 in.) stems.

S. reflexum, with blue green, needle-like leaves and yellow flowers in midsummer, may need a more protected location. Showy stonecrop (S. spectabile) has pink flowers in late summer. ‘Vera Jameson’ is 23 to 30 cm (9–12 in.) in height with red purple leaves and pink flowers in late summer. The following newer introductions have not been tested all across the prairies for hardiness, but have been grown successfully in some areas. It’s best to treat them as annuals until they prove otherwise and you won’t be disappointed. ‘Angelina’ has yellow flowers and golden-yellow foliage; place in a sheltered location. ‘Autumn Charm’ is a sport of ‘Autumn Joy’ with sturdy foliage. ‘Bertram Anderson’ produces purple-red flowers over burgundy-black foliage. ‘Brilliant’ has pink to rusty red flowers. ‘Elsie’s Gold’ is a dwarf ‘Autumn Joy’ with golden variegation and pink flowers. ‘Frosty Morn’ is taller (60–75 cm/24–30 in.) with pink flowers and green and white variegated foliage. S. spurium ’John Creech’ has bright green foliage and mauve-

‘Frosty Morn’ is a newer tall sedum (Sedum) introduction, not yet widely tested, with pink flowers and green and white variegated foliage.

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pink flowers. S. cauticola ‘Lidakense’ has pink flowers and blue green foliage; it is suitable for a more protected location.

‘Matrona’ has soft pink flowers, red stems and green foliage. ‘Neon’ has neon pink flowers over grey-green foliage. Oregon stonecrop (S. oreganum) has yellow flowers and green foliage. ‘Postman’s Pride’ has pinkish-red flowers and dark brown foliage. S. cyaneum ‘Rose Carpet’ sports deep pink flowers and blue green foliage. S. spurium ‘Voodoo’ has rosy flowers and deep red leaves. ‘Xenox’ has dusty rose flowers and grey-blue foliage. CARE: Plant in full sun on well-drained soils. USE: Sedums are excellent as ground covers in hot, dry

areas, in rock gardens, as edging or as pavement plantings among flagstones or patio paving stones and in containers. Butterflies are attracted by their nectar. Overwinter a few in a dish garden indoors.

Hens and chicks, house leek (Sempervivum spp.)

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Sedum kamtchaticum ‘Variegatum’ has been grown in prairie gardens for decades.

Like the sedums, there have been many recent introductions (largely untested in terms of hardiness) of hens and chicks as these succulents become increasingly popular, especially for containers. The genus name, Sempervivum, means always alive and refers to the plant’s longevity and the belief that its presence on a rooftop would ward off fire and lightning. So entrenched was this belief in the Middle Ages that legislation once decreed that hens and chicks be planted on roofs as a sort of insurance. (I checked with my agent but she wouldn’t go for the idea.) It is still found on roofs in Great Britain, hence the common name, house leek. Hens and chicks bear a close resemblance to a miniature artichoke (the hen) surrounded by even more diminutive artichokes (the chicks). It is monocarpic – the “hen” dies after flowering – but the “chicks” live on. It is grown primarily for its succulent evergreen foliage, which is seldom over a few centimetres (2 in.) high. In midsummer, however, it produces a weird, umbrella-shaped flower stalk with small, daisy-like flowers in white, cream or pink. ‘Ashes of Roses’ has deep pink flowers and purple foliage with green accents and silver hairs.

Hens and chicks or house leek (Sempervivum spp.) were once planted on rooftops in the belief that they would ward off fire and lightning.

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‘Icicle’ has dense, coarse hairs on its leaf margins. ‘Oddity’ has distinctive tubular leaves. ‘Purple Beauty’ has pink flowers and large, reddish-purple rosettes. ‘Silverine’ has reddish flowers and red foliage with a silver overlay. Cobweb (S. arachnoideum) has pink flowers with green rosettes covered in cobweb-like hairs. S. calcareum produces light pink flowers and green foliage with brown tips. S. soboliferum has pink flowers with green foliage. CARE: Plant in a hot, sunny location on poorer, well-drained soils. USE: It is excellent in rock gardens, for edging, among paving

stones, as a ground cover in hot, dry locations and in containers. Bring a few indoors for a winter dish garden. Cobweb hens and chicks (S. arachnoideum) is covered in cobweb-like hairs.

Sea campion (Silene uniflora, syn. Silene maritima, S. vulgaris subsp. maritima) Sea campion is a member of the pink or carnation family, native to the seacoasts of western Europe. From June to October, it is covered with masses of tiny white flowers with distinctly notched petals. The calyx below the flowers are often inflated. The leaves are a silver-green and the trailing stems give the 15 cm (6 in.) plant a soft, mound-like appearance. Plants are shortlived but self-seed. ‘Compacta’ has light pink flowers over low mounds of grey foliage. CARE: Plant in full sun in a well-drained location. They are salt

tolerant. USE: They are excellent as a ground cover, in cottage gardens or for naturalizing in hot, dry locations. Seedlings will soon overrun rock gardens.

False solomon’s seal (Smilacina racemosa) Its natural habitat is moist, shady areas of North America, Native to the sea coasts of western Europe, sea campion (Silene uniflora) has pink or white notched petals.

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including the Canadian prairies. Yet when I accidently transplanted a bit of it with another plant to a situation in full sun where it was never watered again, it did very well and proved

surprisingly drought tolerant. It is best sourced though a nursery specializing in native plants. The tiny white flowers on arching stems arise in terminal clusters in spring, followed by red berries. The soft green foliage turns golden in fall. The roots are thick. Plants are 30 to 60 cm (12–24 in.) in height. Starry Solomon’s seal (S. stellata), also native to the prairies, is the same height. It produces loose, open racemes of white flowers at the end of the stems, followed by green berries. The foliage is light green. It makes an excellent ground cover in dry shade but is too aggressive for a border. CARE: Plant in sun or shade on a variety of soils. They are

drought tolerant once established. USE: Naturalize under trees or use in wild gardens or as ground

covers. They are too invasive for a border.

Goldenrod (Solidago hybrids)

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Native to North America, where the species is a pernicious weed, goldenrod was long blamed for causing hayfever (which it does not). The genus name is from the Latin solido, meaning to make whole or strengthen, a reference to its past medicinal

False Solomon’s seal (Smilacina racemosa) has tiny white flowers in early spring that are followed by clusters of red berries.

use. Outstanding hybrids have been developed in Europe and are now finding their way into North American gardens. Many lack the invasive tendencies of the species but remain terrifically drought tolerant. ‘Crown of Rays’ has large, bright yellow heads and reaches to 60 cm (24 in.). ‘Golden Baby’ (‘Baby Gold’) has a long bloom period and is 60 to 70 cm (24–28 in.) high. ‘Golden Fleece’ is compact with dense panicles. ‘Goldrush’ is compact (only 30 cm/12 in.) with dense flower heads. ‘Laurin,’ with a height and spread of 30 cm (12 in.), has golden-yellow flowers in triangular heads. ‘Little Lemon’ is a petite (36 cm/14 in.) plant with lemonyellow flowers. CARE: Plant in full sun and well-drained soil. Powdery mil-

dew may be a problem. Deadhead to prevent self-seeding. Contain overzealous plants with a sharp spade.

Newer introductions of goldenrod (Solidago spp.) are generally shorter and with much less aggressive personalities.

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USE: Use in perennial borders, cottage gardens, as cut flowers, massed and naturalized. It is a nectar plant for bees and butterflies.

Scarlet mallow (Sphaeralcea coccinea, syn. Malvastrum coccineum)

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This is a startlingly attractive plant when in full bloom, but it demands nothing more than to be left alone. Native to the prairies, mallow has deep, woody roots and is often found along road allowances in some of the least inviting, gravelly soils. Sphaer is from the Greek word for globe and refers to the spherical-shaped fruit; alcea is a reference to its relationship with the genus Alcea or hollyhock. Coccinea means scarlet and describes the flowers, which vary from a deep salmon to orange-red and are held above attractive, silver-green foliage from May to June. These prostrate plants form a mat only 15 to 20 cm (6–8 in.) in height. CARE: Plant in full sun on well-drained soils. Grow them lean

Scarlet mallow (Sphaeralcea coccinea) is one of my favourite native garden plants. The flowers vary from deep salmon to orange-red.

and mean, without supplemental fertilizer or water. Purchase plants from a nursery specializing in native plants. They may be difficult to transplant even as young seedlings, so disturb the root ball as little as possible. USE: This is a good plant for rock gardens, perennial borders, among paving stones or for edging.

Lambs ears and big betony (Stachys spp.)

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Lambs ears (S. byzantina, syn. S. lanata, S. olympia) is a plant that invites petting. The common name is the perfect descriptor. Stachys is from the Greek word for spike and describes the flower. Byzantina means of Byzantium or Istanbul; it is native to the Caucasus, Turkey and Iran. The whorls of pink to purplish flowers are held on 10 to 15 cm (4–6 in.) spikes from midsummer to frost. It is grown mainly for the soft, silver-grey, woolly foliage, which indeed resembles lambs’ ears. Plants are 30 to 45 cm (12–18 in.) in height and spread slowly. ‘Big Ears’ (‘Helen von Stein’) has larger leaves that are more olive-green than grey. ‘Silver Carpet’ is a dwarf cultivar that seldom flowers and Lambs ears (Stachys byzantina) need full sun and excellent drainage to do well. Standing water will kill them.

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makes an excellent ground cover. CARE: Plant in full sun on well-drained soil. Standing water in

late winter or early spring will be its death knell. Remove the

flowers if you feel they detract from the foliage. Many gardeners have experienced exceptional growth one year and dieback in another. Good drainage is one of the keys to survival. USE: Stachys is excellent in borders, rock gardens or cottage gardens, for edging or massing. It is a nectar source for bees. In England, it is much used as a companion plant with roses. Big betony (S. macrantha, syn. S. grandiflora) differs from the preceding one in that it is grown primarily for its violet to pink flowers rather than its foliage. The species name, grandiflora, means large-flowered. In early summer, whorls of purple flowers are held above mounds of bright green, somewhat wrinkled, heart-shaped leaves with scalloped edges. Plants are 30 to 60 cm (12–24 in.) in height and spread. It is native to the Caucasus Mountains. Stachys monieri ‘Hummelo’ has bright green, wrinkled leaves with scalloped edges and spikes of pinky-purple blooms in late summer and fall. CARE: Plant in full sun or partial shade in well-drained soil. USE: Use in borders, rock gardens or cottage gardens, for edg-

ing or massing or as a ground cover under trees and shrubs. It is also valuable as a cut flower.

Big betony (Stachys macrantha) produces whorls of purple flowers in early summer.

‘Goldsmith’ comfrey (Symphytum grandiflorum) Symphytum is from the Greek phrase meaning to grow together, an allusion to its healing properties. Comfrey is from the Middle English cumfirie, meaning to cause coagulation of wounds. Native to Europe, comfrey has escaped from cultivation in many parts of North America. The root system is deep and penetrating. While one could not, with a clear conscience, recommend the rampant and indestructible species of comfrey that occupied a prominent place in the gardens of early prairie homesteaders, the cultivar ‘Goldsmith’ is a welcome addition to any border. It grows well in shade, forming a slowly increasing clump of light green and creamy-yellow variegated foliage, reaching about 60 cm (24 in.) or more in height and spread. The light blue flowers appear in late spring and early summer. CARE: Plant in full to partial shade. It is drought tolerant once

established. USE: Use in shade gardens.

‘Goldsmith’ comfrey (Symphytum grandiflorum) is a non-aggressive, clumpforming comfrey.

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False lupine, thermopsis (Thermopsis caroliniana) Thermopsis is from the Greek and means lupine-like. The species name, caroliniana, is a reference to the Carolinas, an area to which it is native. Yellow, lupine-like flowers bloom in spring and are followed by flat seed pods. Plants are about 1 m (3 ft) high, with attractive, blue green, compound leaves. Like other legumes, false lupine is adapted to poor soils and has the ability to fix nitrogen from the atmosphere. It takes a while to clump up. The native T. rhombifolia is a better garden plant if you can find it. CARE: Plant in full sun in ordinary soil. It spreads slowly and resents root disturbance. It may be subject to powdery mildew. USE: Use in the border, for naturalizing and as a cut flower.

Thyme (Thymus spp.)

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You’ll never regret having thyme on your hands or in your garden. There are many species and varieties. Mother-of-thyme (T. Adapted to poor soils, false lupine (Thermopsis caroliniana) has yellow, lupine-like flowers in spring.

serpyllum) has now been split into the unpronounceable T. pulegioides (still mother-of-thyme) and T. praecox (creeping thyme). While Ukrainian thyme (botanical name unknown) still graces the cemeteries of older Ukrainian Orthodox churches in many prairie communities, it is sadly absent from garden centres. Woolly thyme (T. pseudolanguinosus) remains! Thymus is the ancient Greek name for this plant. Thymes are miniature members of the mint family, with square stems, opposite leaves and pink, purple or white flowers on short spikes in midsummer. Lemon thyme (T. x citriodorus) smells like lemon and is best placed in a protected location. Creeping thyme (T. praecox) forms flat mats with very tiny, evergreen leaves. ‘Albus’ has white flowers. ‘Doone Valley’ is green variegated with bright gold in spring under cooler temperatures. Not as hardy as the others, it is best placed in a protected location. ‘Pink Chintz’ looks like woolly thyme but with darker foliage and salmon-pink flowers

Creeping thyme (T. praecox) is dependably hardy, forming flat mats with pink or white flowers.

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Woolly thyme (T. pseudolanuginosus) is even lower, forming a mat of grey foliage with pink flowers. When used as

a pavement planting among flagstones, it tolerates foot traffic surprisingly well. Mother-of-thyme (T. pulegioides, syn. Thymus serpyllum), forms a tight mat of dark green foliage, 15 cm (6 in.) in height and is covered in a mass of tiny purple flowers in midsummer. It spreads by creeping rootstock. ‘Album’ has white flowers. ‘Bertram Anderson’ has mauve flowers over bright green, creeping foliage. CARE: Plant in full sun on well-drained soils. The leaves are

evergreen, so wind protection and snow cover are helpful. USE: Thymes are ideal in rock gardens, planted among paving stones, as ground covers or for edging paths. They are a nectar source for bees and butterflies.

Veronica, speedwell (Veronica spp.)

Lemon thyme (Thymus citriodorus) smells like lemons and is best placed in a protected location in colder areas.

Speedwells form a large group of perennials, some of which are both hardy and drought tolerant. Many have graced prairie gardens for decades. Flower colour ranges from blue through pink and white and heights from ground-hugging mats to spikes of almost 1 m (3 ft). The genus name, Veronica, is associated with St. Veronica for reasons lost to antiquity. Hungarian speedwell, Austrian speedwell (V. austriaca, syn. V. teucrium) is a prostrate species with a height of only 15 cm (6 in.) and double the spread that is native to southern Europe. ‘Trehane’ is a wonderful selection with yellow foliage and contrasting blue flowers in July, but it may be short-lived. Gentian speedwell (V. gentianoides), from the Caucuses, produces loose racemes of small, pale blue flowers in early summer, 15 to 50 cm (6–20 in.) above a mat of glossy, 5 cm (2 in.) long leaves. It is only moderately drought tolerant. Woolly speedwell (V. incana)

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native to Russia, has

spikes of violet-blue flowers in July, 30 to 45 cm (12–18 in.) above mat-forming, silver grey foliage. Turkish speedwell (V. liwanensis) has tiny evergreen leaves and delicate blue flowers from May to June. Comb speedwell (V. pectinata) produces tiny, deep blue flowers with a white centre in June and July. The small, oval leaves are toothed. With a height of 8 to 15 cm (3–6 in.), it

Russian speedwell (V. peduncularis) is worthy of trial and best placed in a sheltered spot.

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forms a prostrate, grey mat. Both the common and species name describe the leaf shape, which resembles a comb used to card wool, a reference that is probably lost on most gardeners today. Russian speedwell (V. peduncularis) has bright blue flowers in early summer. Untried through most of the prairies, it is best placed in a sheltered location. ’Aztec Gold’ (V. prostrata), with a height and spread of 30 by 40 cm (12 x16 in.) has lime-green to gold foliage and blue flowers. Creeping speedwell (V. repens) has light blue or white flowers in late spring above mossy green foliage with a height and spread of 5 by 20 cm (2 x 8 in.). Spike speedwell (V. spicata), with a height and spread of 15 by 75 cm (6 x 30 in.), is the tallest of the drought-tolerant veronicas and has the greatest number of cultivars. Native to Europe and Asia, it blooms over a long period from late summer to fall. It sometimes gets powdery mildew. ‘Blue Spires’ (75 x 30 cm/30 x 12 in.) has blue flowers. ‘Giles Van Hees’ (15 x 30 cm/6 x 12 in.) is a dwarf dark pink. ‘Red Fox’ (40 x 30 cm/16 x 12 in.) has deep pink flowers. ‘Red Fox’ is an older cultivar of spike speedwell (Veronica spicata).

‘Royal Candles’ (40 x 30 cm/16 x 12 in.) is violet-blue. ‘Sunny Border Blue’ (50 x 30 cm/20 x 12 in.) is blue. Whitley’s speedwell (V. whitleyi)

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has blue flowers in

spring over a grey-green mat of foliage (5 x 20 cm/2 x 8 in.). CARE: Speedwell prefers full sun and well-drained soils. Woolly speedwell can be rejuvenated after flowering by shearing. USE: Depending on their height, speedwells are valued as

cut flowers, as dense ground covers, among paving or patio stones, as edging, in rock gardens and as border plants. They are a nectar source for bees.

Culver’s root (Veronicastrum virginicum, syn. Veronica virginica)

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Culver’s root is closely related to the veronicas. It is native to North America, including a very small (and endangered) population in Manitoba. It was grown and sold by the Shaker Comb speedwell (Veronica pectinata) has tiny blue flowers with a white centre and forms a prostrate grey mat.

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community of Massachusetts as a medicinal plant in the early 1820s. Culver was apparently an early pioneer doctor or practitioner who popularized the medicinal use (the roots served as a

purgative) of this plant. Widely used by Indigenous peoples for a variety of ailments, it was included in the first United States Pharmacopeia published in 1820. The flowers, generally white but also pink or pale blue, are formed in dense spikes on long, sturdy, arching stems in late summer. Plants are 1 to 1.2 m (3–4 ft) in height forming large, upright clumps. Leaves are dark green, arranged in whorls around the stems. ‘Alba’ has white flowers. ‘Fascination,’ with lilac-purple flowers, was selected for its fasciated flower stems, 90 to 120 cm (3-4 ft) in height. ‘Rosea’ is pink. CARE: Plant in full sun to partial shade. It is adaptable to vari-

ous soils and is very drought tolerant once established. USE: Use in borders and as a cut flower. It attracts bees and

butterflies.

Canada violet (Viola canadensis, syn.V. rugulosa)

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One of a handful of perennials that tolerate dry shade, the

Culver’s root (Veronicastrum virginicum) is large, lovely, and very drought tolerant with flowers in pink, white and lilac-purple.

Canada violet is outstanding when used as a ground cover. Viola may be derived from the Latin word via, which means road or way. The implication is that these are flowers found along the way. The genus name canadensis means of Canada, to which they are native. The fragrant white flowers, with pink to purple veins, are produced above heart-shaped leaves in midsummer. The plants are 25 to 38 cm (10–15 in.) in height. They spread by rhizomes and can be invasive if placed in a border. CARE: Plant in shade on well-drained soil. USE: Excellent as a ground cover in dry shade or for natural-

izing. In a shady border, it is too aggressive.

Barren strawberry, Siberian barren strawberry (Waldsteinia ternata)

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Barren strawberry is an extremely popular plant in Europe but is little known in Canada and should be much more widely available. It is attractive, extremely hardy (it is, after all, native to Siberia), long-lived and adaptable. It was named to honour Austrian botanist Count Franz Adams Waldstein-Wartenburg (1759–1823). (I imagine him as a small child learning to write his name, as the student next to him is printing

The Canada violet (Viola canadensis) is the ideal ground cover for dry shade.

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“Berg.”) The species name, ternata, means in threes and describes the compound leaflets. It is native from Europe through Japan. The glossy foliage is extremely attractive and strawberrylike. Bright yellow flowers are produced in late spring. The low plants (10 x 30 cm/4 x 12 in. in height and spread) root and spread by creeping rhizomes. CARE: Plant in sun or light shade. USE: Use as ground covers or for edging.

Yucca glauca, small soapweed (Yucca glauca)

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We learn about symbiosis, the interdependence of two organisms, in high school. Here is a case in point. The flowers of yucca glauca are fertilized by the pronuba moth, which deposits her eggs where the seed pod will develop, assuring her larvae of a reliable food source upon hatching. The larvae consume some A ground cover adapted to sun or shade, barren strawberry (Waldsteinia ternata) has yellow flowers and strawberry-like foliage.

of the flat, black seeds, but generally leave enough to perpetuate the plant. Yucca is the Caribbean name for a plant that early botanists thought it resembled. The species name, glauca, means glaucous – foliage that is grey-blue or covered with a powdery bloom. The common name alludes to the early use of the roots in soap making. A member of the lily family, yucca is grown primarily for its evergreen foliage: narrow, stiff, grey-green leaves with shredding white margins and tipped with very sharp spines. The creamywhite flowers are bell-shaped, pendulous and produced on 60 to 90 cm (24–36 in.) stalks in July. It has deep roots and is native to the Dakotas, Montana and southern Alberta. CARE: A desert plant, yucca does best on well-drained soils in

full sun. It will not tolerate heavy, wet soils. In those situations, it’s best to berm. Plants take several years to establish. Note that Yucca filamentosa, although widely available, will seldom overwinter on the prairies. USE: Because of its unusual form and texture, yucca is an exceptional accent plant in rock gardens or as a ground cover for hot, dry locations.

Small soapweed (Yucca glauca) is unique. It has stiff, upright grey-green leaves with shredding white margins tipped with spines.

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“Annuals may last for only one season, but they provide instant gratification in a vast array of colours, heights, textures and foliage.”

CHAPTER 9

Annuals Annual flowers may last for only one growing season, but they provide instant gratification in a vast array of colours, heights, textures and foliage. Some are easy to seed directly where they are to be grown. Others are best purchased as young plants. And as a bonus, many will generously reseed from year to year. Since the original edition of Creating the Prairie Xeriscape was published, many new cultivars of drought-tolerant annuals have come onto the market. Each year brings more introductions and it is impossible to list them all. Many have improved form, new colours with greater intensity, a longer flowering period, better branching of the plants and improved disease resistance. On the flip side, several of the older species are no longer as readily available as they once were. Sourcing them will take effort on the part of gardeners. As with other types of plants, the botanical names of annuals keep changing. Gardeners have a love-hate relationship with botanical names. We love them because of their exactness. One plant, one name, right? We hate them because the international committee on nomenclature has an alarming tendency to change them, depending on whether the “lumpers” or the “splitters” gain the upper hand. Many of these annuals have had name changes in the last decade.

Classed as annuals, biennials or short-lived perennials, the single hollyhocks (Alcea spp.) are generally hardier than the doubles. Forego the mulch and allow them to perpetuate themselves through self-seeding.

Precision is difficult when dealing with “annuals.” Quite a few of the plants listed in this chapter are perennials in milder climates but treated as annuals on the prairies. Others are biennials that bloom their first year from seed. Drought-tolerant ratings, as always, are for these plants “once established.” In the case of annuals (or perennials treated as annuals), that means once they have been transplanted successfully and have developed a root system in their new site or the seedlings are well on their way.

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Ageratum, flossflower (Ageratum houstonianum) Low in stature and long in bloom, ageratum is covered in fluffy clouds of tiny blue, pink, mauve or white flowers from early summer until frost. Although the species is taller, most cultivars are of dwarf stature and mound-like in form (15–30 cm/5–12 in., with a spread of 20 cm/8 in.), with pale green, hairy, heart-shaped leaves. The genus name, Ageratum, from a Greek phrase for not growing old, refers to the long-lasting colour of the cut flowers. The species name honours William Houston (1695–1733), a Scottish physician who collected plants in Central America. The common name alludes to its resemblance to candy floss. It is native to Mexico, the West Indies and Central America. Artist series, in blue and rose, is heat tolerant and exceptionally free flowering. The plants are compact (20–30 cm/8–12 in. in height, with a spread of 30 cm/12 in.), uniform and mounding. ‘Bavaria’, a bicolour of powder blue with a white centre, is 36 cm (14 in.) high. Ageratum or flossflower (Ageratum houstonianum) produces large heads of tiny flowers in blue, pink, mauve or white over a long period.

‘Blue Horizon,’ one of the taller ageratums at 75 cm (30 in.) or higher, has large flower clusters. Hawaii series is available in an array of separate or mixed colours. The plants are compact (15 cm/6 in.) and vigorous. ‘High Tide’ is tall (60 cm/24 in.) and vigorous. The flowers are in white or blue. They are “self-cleaning” in that the spent flowers fall off and do not need to be deadheaded. ‘Leilani Blue’ produces uniform 36 to 40 cm (14–16 in.) plants with mid-blue flowers and dark green foliage. The Pearl series flowers prolifically on 30 cm (12 in.), heattolerant plants with no need for deadheading. ‘Royal Pearl’ is a darker blue, ‘Azure Pearl’ a mid-blue and ‘Silver Pearl’ silvery-white. CARE: Plant in full sun to light shade, in well-drained soil to

which organic material has been added. Although droughttolerant and extremely heat-tolerant, they will have better bloom with more even moisture. Pinch back the stems when the plants are young to encourage branching and for a more compact plant. Ageratum are very frost tender and will blacken at freezing temperatures. USE: Dwarf ageratums are ideal for edging, containers and as winThe Artist series of ageratum (A. houstonianum) has compact, heat-tolerant plants in blue and rose.

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ter houseplants. Taller types are used in drifts in borders and as cut flowers. Their uniformity lends them to more formal designs. They work well with other pastel flowers. They are nectar plants for butterflies and the seeds are eaten by finches and juncos.

Hollyhock (Alcea spp.)

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Native to China, hollyhocks are tall (about 2 m/6 ft), oldfashioned flowers available in a wide range of colours: white, pink, purple, red and yellow. They are tougher than they look – I’ve seen them emerging from under asphalt. Alcea is the Greek word for mallow, which is in the same family as hollyhock. When introduced to Europe in the 1500s, they were erroneously believed to be from the holy land (thus the common name). Blooming in midsummer, the annual, biennial and perennial types are very similar in appearance. The perennials are short-lived but generally bloom in their first year from seed and perpetuate themselves through reseeding. The seedlings may not always resemble the parent plants. Single-flowered forms appear to be hardier than the doubles. Alcea rosea cultivars include: ‘Black Watch,’ also listed as ‘Nigra’ and ‘The Watchman,’ has single, deep chocolate-maroon flowers and is 1.5 to 2.1 m (5­–7 ft) in height. ‘Chater’s Double Maroon’ has double, maroon-purple flowers.

Spring Celebrities series, lemon, is a new hollyhock (Alcea) introduction selected for its value as a cut flower.

‘Creame de Cassis’ has dark purple, single flowers and reaches 1.5 to 1.8 m (5–6 ft) in height. Fig leafed hollyhock (A. ficifolia) has fig-like leaves, yellow, copper, pink, red, plum or white flowers and is more robust and longer lived than most hollyhocks. Native to Siberia, it is rust resistant. Russian hollyhock (A. rugosa) is native to dry hills from Iran into Russia. It has pale yellow flowers on 2.4 m (8 ft) stalks and is highly resistant to hollyhock rust. CARE: Grow in full sun in deep, well-drained soil. Leaf rust is

sometimes a problem, as are spider mite infestations. USE: Plant in the border and in cottage gardens, in large masses or as single specimens.

Amaranthus (Amaranthus spp.)

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The genus Amaranthus, much beloved by designers of Victorian era formal bedding-out schemes, also includes grains and a few pernicious weeds such as redroot pigweed and tumbleweed. Vitamin- and mineral-rich, amaranth species were used as food crops by Aztecs and Incas and have long been a staple of many Asian diets. The Greek word amarantos means unfading

‘Queeny Purple’ hollyhock (Alcea) is pure purple and very short for a hollyhock, only 50 cm/20 in.

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and refers to the long-lasting flowers. The Greeks sometimes decorated their tombs and temples with images of this plant. Love-lies-bleeding (Amaranthus caudatus), with its exotic look, takes careful placement in contemporary gardens. Caudatus means tail, describing the long, drooping, chenille-like flowers. Native to India, Africa and Peru, it comes into its own in late summer and fall and should be started early. Its melodramatic common name is from the generally blood-red, rope-like panicles hanging from plants 60 to 120 cm (24–48 in.) in height. Other colours include yellow, green, purple or bronze. The leaves are wide and pointed. ‘Dreadlocks’ is unique, with 1 m (3 ft) long ropes of magenta florets. ‘Fat Spike’ is 1 to 1.2 m (3–4 ft) in height, with erect burgundy spikes. ‘Green Cascade’ is 1 m (3 ft) in height with chartreuse flowers that hang in panicles. ‘Green Tails’ has greenish-yellow tassels and green foliLove-lies-bleeding (Amaranthus caudatus) was much loved by Victorian gardeners.

age on 1 m (3 ft) plants. ‘Pony Tails’ is 1 to 1.2 m (3–4 ft) in red or green shades. Joseph’s coat (A. tricolor, syn. A. gangeticus) is originally from Indonesia. It is primarily a foliage plant of 30 to 60 cm (12–24 in.). The flowers, found in the leaf axils, are fairly insignificant. Spinach-like in taste, it is eaten as a green in many parts of Asia. While the lower foliage is green, the upper foliage is almost poinsettia-like. Its brilliant red and yellow leaves are often described in terms of fireworks. ‘Aurora Yellow’ (1.2–1.5 m/4–5 ft) has creamy-yellow upper leaves. ‘Early Splendor’ (1–1.2 m/3–4 ft) is bright crimson above, bronze below. ‘Illumination’ (0.6-1.5 m/2-5 ft) has a blend of yellow, orange and red foliage. CARE: Plant in full sun on poorer, well-drained soils. Do not

Joseph’s coat (A. tricolor) is grown primarily for its striking green, red and yellow foliage.

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overfertilize as colours may lose their intensity in richer soils. Amaranthus are very drought and heat tolerant but have poor frost tolerance. Excessive moisture or poor drainage may cause root rot. Transplant with as little disturbance to the root ball as possible.

USE: Amaranthus are well placed in annual or mixed borders and in fresh and dried arrangements. As a focal point, they often invite comment.

Winged everlasting (Ammobium alatum)

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As the common name implies, these plants have long been used in dried arrangements and their popularity has ebbed and flowed accordingly. Seed is not as readily available as it once was but is worth seeking out. The genus name is derived from the Greek words ammos (sand) and bio (to live), meaning “a plant that lives in sand,” a reference to its natural habitat. Alatum describes the winged stems that make it so easy to identify. Although native to Australia, winged everlastings are well adapted to the warm days and cool nights of the prairies. A perennial, it is treated as an annual in northern climates. Small white daisies with yellow centres and dry, paper-like bracts are produced on branched stems of 45 to 90 cm (18–36 in.). The leaves are grey and felty. ‘Bikini’ has white flowers, 2.5 to 5 cm (1–2 in.) in diameter,

Long used in dried arrangements, winged everlastings (Ammobium alatum) have yellow centres and dry, paper-like bracts.

with yellow centres. It is 30 to 90 cm (12–36 in.) in height. ‘Grandiflora’ is 70 cm (28 in.) in height and has white flowers, 5 cm (2 in.) in diameter, with yellow centres. CARE: Plant in sandy to loam soils in full sun. USE: Winged everlastings are generally grown as dried flow-

ers. The white cultivars are especially valued because they do not fade with age. Cut the stems just before the flowers open and hang them upside-down.

Pimpernel (Anagallis spp.)

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“They seek him here, they seek him there...that damned elusive Pimpernel.” The scarlet pimpernel (Anagallis arvensis), made famous by the novel set in France during the French Revolution (and later films of the same title), is perhaps the best known of this genus. Anagallis, which means delightful or to laugh, was the Greek common name as the sight of pimpernels were thought to lighten a heavy heart. Scarlet pimpernel (Anagallis arvensis) was once known as the poor man’s weatherglass or barometer because the flowers close on dull days or when the temperature begins to fall. A trailing plant with a height of 15 to 25 cm (6–10 in.) and up

The scarlet pimpernel (Anagllis arvensis) is not often seen in prairie gardens, but is a good choice for borders and containers.

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to 70 cm (28 in.) in spread, it has bright scarlet flowers with a charm all their own. Native to Europe and into Asia, in the past it was considered a weed of cultivated fields. Blue pimpernel (A. monellii) is blue, blue, blue! A perennial treated as an annual, the blue pimpernel is native to the coastal dunes of the Mediterranean and is very drought tolerant. Somewhat sprawling, it is a good filler that weaves other plants together. The flowers are dark blue tinged with red and are borne in the upper leaf axils. The leaves are small, dark green and oval. Species and cultivars are 15 to 60 cm (6–24 in.) in height. ‘Gentian Blue’ is a compact plant of only 15 to 23 cm (6–9 in.) with a profusion of blue flowers. ‘Skylover’ is a large, branching plant used extensively in containers. The 2.5 cm (1 in.) blue flowers have violetpink centres. ‘Wildcat Blue’, ‘Wildcat Mandarin’ and ‘Wildcat Orange’ have a fine texture and are great in hanging baskets. CARE: Plant in full sun on well-drained soil. USE: Place toward the front of an annual or mixed border, in a rock garden, as edging or in containers or hanging baskets. ‘Wildcat Blue’, a new introduction of the blue pimpernel (A. monellii) has a fine texture and is great in hanging baskets.

Angelonia, summer snapdragon (Angelonia angustifolia) Another recent introduction to North American gardens, angelonia is native to South America. Although first introduced to Britain prior to 1850, the newer cultivars are the result of intensive plant breeding in the last decade. The result is a heat-loving, continuously blooming and low-maintenance plant. The flowers, held on long erect stems of 30 to 60 cm (12–24 in.), are 2.5 cm (1 in.) in diameter, lipped and resemble snapdragons, hence the common name. They are available in white, pink, blue or purple. Angelface series, in blue, pink, white and dark violet, is 60 cm (24 in.) in height. Angelmist series includes blue, purple, pink, white and bicolour flowers on plants 10 to 25 cm (4–10 in.) in height. Carita series has pink, purple and white flowers on cascad-

Native to South America, angelonia or summer snapdragon (Angelonia angustifolia) are available in white, pink, blue or purple.

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ing plants of 40 to 50 cm (16–20 in.). ‘Serena,’ a seed-grown cultivar, comes highly recommended. Colours include lavender, pink, purple and white. Plants are 25 to 30 cm (10–12 in.) in height with a spread

of 30 to 35 cm (12–14 in.). They are well branched, compact and full, with no need for pinching the growing points. CARE: Place in full sun on well-drained soil. They may need

occasional watering. There is no need for deadheading. USE: Plant in beds and large containers; also use as a cut flower.

Blue-eyed African daisy (Arctotis x hybrida)

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These stunning plants are native to South Africa. Daisy-like flowers are borne singly on long stems. The flowers are 7.5 cm (3 in.) in diameter, with blue centres rimmed in gold. The petals range from white through cream, orange, yellow, pink, mauve, wine and red, with lavender undersides. Plants are 30 to 60 cm (12–24 in.) high, with finely cut, silver-grey foliage. Otherwise free flowering, they close on cloudy days. A tender perennial, it is treated as an annual in colder climates. The species from which it is derived, A. venusta and A. fastuosa, are seldom available and seed of Arctotis may be difficult to source. Vegetatively propagated plants are widely available. Thompson & Morgan hybrids are in intense colours of pink,

Blue-eyed African (Arctotis x hybrida) daisies almost seem to shimmer. White, cream, orange, yellow, pink, mauve, wine or red petals surround blue centres.

white, yellow and orange over finely cut, silver-green foliage, 30–40 cm (12–16 in.) in height. CARE: Plant in sandy soil and full sun. They perform well where

nights are cool. USE: Use in annual and mixed beds.

Beggar’s tick, tickseed (Bidens ferulifolia) The common name refers to the barbed fruits of some Bidens species, which stick to anything or anyone passing by, distributing them far and wide in such a fashion. The genus name is from the Latin words bis, meaning twice and dens, toothed, another reference to the hooked seed. Closely related to cosmos, tickseed is native to the southern United States, Mexico and Guatemala. It is yet another tender perennial treated as an annual. The yellow, daisy-like flowers are 3 to 4 cm (1.5 in.) in diameter with petals surrounding a central bronze disc. Like cosmos, they are held on thin, wiry stems (up to 80 cm/32 in.) and are somewhat floppy, making them ideal for containers. The bright green, ferny foliage is pinnately compound, each leaf composed of many small leaflets, arranged like a feather. ‘Biddy Gonzales’ is 20 to 25 cm (8–10 in.) in height and has large, golden-yellow flowers.

Tickseed (Bidens ferulifolia) has come into its own as an annual for hanging baskets and other containers.

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‘Peter’s Gold’ is a vigorous yet compact cultivar of 38 cm (15 in.) that is both heat and drought tolerant. ‘Solaire Compact Yellow’ is 30 cm (12 in.) with bright gold flowers. CARE: Plant in full sun to partial shade in well-drained soil.

Containers should have even moisture. They do not require deadheading and will reseed to a limited extent. USE: Use in containers, mixed borders, as a seasonal ground cover, for edging, in gravel beds and cascading over low walls. They are a nice filler for hanging baskets.

Great quaking grass, trembling grass (Briza maxima)

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One of the first annual grasses to be grown as an ornamental, quaking grass has been in cultivation for over two centuries. The genus is from the Latin name of a grain crop, which in turn came from the Greek brizo, meaning nodding or sleepy, a reference to the delicate flowers that nod in the slightest breeze. Maxima means larger (there is also a Briza minor). Native to the Mediterranean region of Europe and Asia, it has become widely naturalized in The flowers of great quaking grass (Briza maxima), resemble a locket or puffed wheat.

California and can be somewhat weedy even on the prairies. Plants reach a mature height of 45 to 60 cm (15–30 in.), with a 20 cm (8 in.) spread. The narrow, strap-shaped, green leaves are about 20 cm (8 in.) long. Nodding flowers are held on slender stems in loose panicles, described variously as resembling a locket or puffed wheat, and turn from light grey to purple as the season progresses. CARE: Place in full sun on well-drained soil. It does better on

poorer soils lacking nutrients. USE: Use in beds and borders, massed and naturalized; it is also useful in dried arrangements.

Calendula, pot marigold (Calendula officinalis) Originally an herbal rather than an ornamental plant, the petals are still used as an edible garnish, although they may be toxic if consumed in large quantities. It was also used as an early dye substitute for the more costly saffron. Calendula is from a Latin phrase meaning throughout the months, a reference to its long blooming period. (The English Calendula or pot marigold (Calendula officinalis) was once a medicinal and dye plant.

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word “calendar” is similar in origin.) The word officinalis means of the pharmacopoeia and refers to its past medicinal use for the treatment of ulcers, cuts, bruises and warts. The common name,

pot marigold, has two possible origins: the earliest is thought to be a contraction of “Mary’s gold,” alluding to the Virgin Mary, while “pot” is ascribed to its use as a pot herb or vegetable. Native to southern Europe and the Mediterranean, calendulas were grown in herbal gardens during the Middle Ages. In more recent times, they have become widely naturalized on disturbed soils elsewhere. They have long been a favourite in rural prairie gardens, where they flourish with our cool night temperatures. Calendulas bear large (7–10 cm/3–4 in.), solitary, daisy-like flowers in shades of orange red, orange, apricot, yellow and cream. The flowers, which may be single or double, close at night. Plants are upright, 30 to 45 cm (12–18 in.) in height, with a spread of 30 to 60 cm (12–24 in.). The green leaves are spoon- or lanceshaped. All plant parts are strongly aromatic when crushed. ‘Apricot Twist’ is a compact plant (30 cm/12 in.) with double, apricot blooms. Bon Bon series has double flowers in orange, apricot and yellow. It is an early, free-flowering, dwarf hybrid of 30 cm (12 in.) and good for pots. Citrus Smoothies series has flowers of apricot or lemon yellow, each with a cream edge, 10 cm (4 in.) diameter, on

‘Apricot Twist’ is a compact calendula (C. officinalis) with double apricot blooms.

50 to 60 cm (20–24 in.) plants. Flashback mix (30–60 cm/12–24 in.) has petals of yellow to orange with darker maroon on the backside. Kablouna mix has double flowers in vibrant colours of gold, orange, and lemon with pompom centres on 45 to 60 cm (18–24 in.) plants. Pacific Beauty mix is 45 cm (18 in.) in height, with uniform, long-stemmed, long blooming, double flowers in shades from cream to red. ‘Touch of Red’ has flowers in buff, orange and yellow with petals tipped in red and is 36 cm (14 in.) in height. CARE: Plant in full sun or light shade in poorer soils with good

drainage. It can be directly sown or transplanted. Calendula is heat and drought tolerant and will tolerate light frost. Deadhead for continuous bloom. Aster yellows, a viral disease, is sometimes a problem, as is powdery mildew. USE: Use in containers, annual or mixed borders, cottage gardens, for mass bedding and as cut flowers. Calendula has recently regained popularity in “hot” gardens emphasizing colours such as yellow, orange and red. The flowers have been used as a dye (not so long ago to colour butter) and both flowers

Flashback mix calendula (C. officinalis) has petals ranging from yellow to orange with dark maroon backsides.

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and leaves can be added to salads and stews. It is a nectar plant for butterflies.

Safflower (Carthamus tinctorius)

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Native to Egypt and other parts of Asia, safflower has long been used as an oilseed plant and dye source. The genus name is derived from the Arabic qurtom and the Hebrew qartham, meaning to paint and referring to the traditional use of the flowers as a dye. The thistle-like plants reach 1 m (3 ft) in height. The lower leaves are oval and slightly toothed while the upper leaves are sessile, without a leaf stalk. The flowers, like those of thistles, are 3 cm (1–1.5 in.) in diameter, globe-shaped, in scarlet, orange and yellow or cream and bloom in July and August. Gold cultivars appear more vigorous and floriferous than white ones. ‘Gold Tuft’ has golden-orange round flower heads and is 60 to 90 cm (24–36 in.) in height. Long used as an oilseed plant and dye, safflower (Carthamus tinctorius) has large yellow flowers and thistly foliage.

‘Lasting Orange’ is 60–90 cm (24–36 in.) and spineless with darker orange petal tips. ‘Lasting Yellow’ is similar but in yellow. Quadricolor is a mix of orange, yellow, cream and gold plants, 60 to 75 cm (24–30 in.) in height. CARE: Place in full sun and well-drained soil. USE: Use in borders and cottage gardens as well as fresh and dried cut flower arrangements.

Vinca, Madagascar periwinkle (Catharanthus roseus) Native to Madagascar, vinca has become a weed in the tropics, where it has quickly naturalized. It is becoming more widely used by prairie gardeners, an environment in which it has a very slim chance of becoming weedy. Catharanthus is from a Greek phrase meaning a pure flower, while roseus means rose-coloured. Modern breeding has produced larger, longer blooming, more phlox-like flowers in a greatly expanded colour range. The original species has recently been found to contain alkaloid compounds useful in the treatment of leukemia. The single, five-petalled, pink-centred flowers, produced in Titan mix vinca or Madagascar periwinkle (Catharanthus roseus) has phlox-like flowers in a greatly expanded colour range from white through pink and purple.

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the leaf axils and at the end of the stems, are available in white, pink, rose, lavender or purple. The pointed leaves are glossy, leathery and dark green. Plants are up to 30 cm (12 in.) or higher, with a spread of twice that. All plant parts are poisonous. ‘First Kiss Blueberry’ is a new colour of violet blue on 30 cm

(12 in.) plants with good basal branching. Flowers are 5 cm (2 in.) in diameter with a darker eye. Heat Wave mix (25 cm/10 in. in height) is earlier blooming and available in many colours, including apricot, blue, rose and pink. It is extremely heat (and cold) tolerant. Stardust mix produces 4 cm (1.5 in.) flowers in orchid, pink, magenta and white on plants 30 to 50 cm (12–20 in.) in height. They do not need deadheading. CARE: Plant in full sun or partial shade in sandy loam soils.

Pinch older varieties to encourage branching. Over-watering may cause rot. They need heat to thrive. USE: If you like the look of impatiens but are dealing with a hot, dry area, try vinca. Use in beds, hanging baskets, containers and as a ground cover.

Cockscomb (Celosia argentea var. cristata) Resembling a genetically modified plant more than one that is likely to be found in nature, Celosia is, in fact, native to central Asia, but selections have been made for their appeal to garden-

Vinca (C. roseus) looks similar to impatiens but is much more adaptable to hotter, drier areas.

ers who like their plants a bit out of the ordinary. The Victorians, with a penchant for the weird, found this genus particularly attractive. Celosia is from the Greek word kelos, meaning burned, which describes the brilliant flower colour. The common name alludes to the crested form of the flowers, which resemble the comb of a rooster. The velvety flowers, in terminal or axillary spikes, look like a cockscomb, but have also been described as resembling coral or the human brain. Colours range from pink, red, orange, bronze and salmon through to gold and white. Flowers are long-lasting (up to two months). Plants vary from 15 cm to 1 m (6–36 in.) or more in height, with green or bronze-purple foliage. Cockscomb invites comments from visitors, but because of its unusual form and texture, it needs careful placement in the garden. They don’t “fit” every situation. ‘Amigo Mahogany Red’ is dwarf (15 cm/6 in.) with maroon blooms and dark purple foliage. It is intended for containers. ‘Prestige Scarlet’ has 7 cm (3 in.), deep red flowers over greenbronze foliage, 45 cm (18 in.) in height. Triangle mix has ribbon-shaped combs in five different colours on tall (1 m/3 ft) plants with sturdy stems.

The velvety flowers of cockscomb (Celosia argentea var. cristata), are said to resemble the human brain, coral, or indeed the comb of a rooster.

CARE: Grow in full sun on well drained soil. They are moderately

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drought tolerant once established. This frost-tender tropical plant does best during a long, hot summer. Too much water can result in rot. USE: Cockscomb is well suited to a border as well as contain-

ers. Dwarf types are used for edging. All are excellent in fresh or dried arrangements.

Dusty miller and bachelor’s button (Centaurea spp.)

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Composed of both annuals and perennials, the genus Centaurea was named after the mythical Greek half-horse/half-human centaurs, who were said to have used these plants to heal wounds. Their flowers are characterized by an involucre, a whorl of overlapping bracts, just below the flower. With brilliant colour and an unusual form and texture, cockscomb (Celosia argentea var. cristata), appeals to gardeners with a penchant for something different, but will need careful placement.

Dusty miller (Centaurea cineraria, syn. C. gymnocarpa) is one of several annuals with silver grey foliage with the common name of dusty miller (see also Jacobaea maritima and Tanecetum ptarmiciflorum). Cineraria means ashen grey, the colour of the deeply lobed, felt-like leaves. The farina on the leaves of all of these resembles a miller covered in flour dust, thus the common name. Varying in height from 15 to 45 cm (6­–18 in.), with a spread of about 20 cm (8 in.), these plants are grown mainly for their foliage. The purple flowers are small and inconspicuous. A perennial in milder climates, it is treated as an annual on the prairies. It is readily available as seed or bedding plants. CARE: This heat- and drought-tolerant plant does well in full

sun in well-drained soil, such as sandy loam. USE: It is excellent for edging, annual beds, formal design and containers. Its soft grey foliage serves as a foil for the flamboyant colours of brighter annuals, but it is equally effective in a pastel border. Bachelor’s button, cornflower (C. cyanus) is an old-fashioned annual that has graced gardens for centuries. Native from southeastern Europe into western Asia, it is widely naturalized elsewhere. Cyanus, a Greek word for blue, refers to the flower colour. Cornflowers were once a common weed in Dusty miller (Centaurea cineraria) is one of several annuals with the same common name. Excellent for edging, annual beds, and more formal design.

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fields of wheat (which the British call corn), hence the common name. As well, they were used as a buttonhole flower for young men going courting, thus the other common name. The frilly flowers, with bracts at their base, are in shades of blue, purple, wine, deep rose, red, pink or white and up to

5 cm (2 in.) in diameter. Some are almost double. The narrow leaves are grey-green and aromatic. Plants vary in height from 30 to 90 cm (12–36 in.), with a spread of about 30 cm (12 in.) and can be floppy. ‘Black Ball’ (75 cm/30 in. in height) is a unique shade variously described as the colour of milk chocolate, a deep brownish red or dark mauve. ‘Blue Boy’ (75 cm/30 in. high) has double flowers of intense deep blue. Polka Dot mix produces double flowers in blue, pink, white and maroon on 60 cm (24 in.) plants. CARE: Cornflowers thrive in poorer, well-drained soils in full

sun or partial shade. Successive sowing and deadheading result in prolonged bloom. Do not overfertilize. USE: Plant in informal drifts, cottage gardens and as fillers in mixed borders; use as fresh or dried cut flowers or in your lapel when you go a courtin’.

Once sported by young men going a courtin’, bachelor’s buttons (C. cyanus) come in shades of blue, purple, wine, deep rose, pink or white.

Nullarbar buttons, everlasting (Chrysocephalum apiculatum, syn. Helichrysum apiculatum)

This relatively new introduction, native to the Nullarbar Plains of southwest Australia, may be a bit difficult to obtain. The name is derived from the Greek words chrysos, meaning gold and cephalum, head, referring to the stunningly bright flower heads. The species name, apiculatum, is from the Latin and describes the leaves that end abruptly in a sharp point. About 40 cm (16 in.) in height, the stems are decumbent, lying flat but turning up at their tips. The flowers resemble bright yellow balls, 1 cm (0.5 in.) in diameter and are formed in clusters. Very floriferous, new flowers form at the end of the stems and quickly cover the old. The leaves are alternate, linear or lance-shaped, hairy and silver grey. ‘Flambe Yellow,’ 15 to 30 cm (6–12 in.) in height, has tufted yellow flowers against silvery foliage. Low growing and trailing up to 60 cm (24 in.), it is extremely drought- and heat-tolerant and ideal for hanging baskets. CARE: Plant this very heat-tolerant plant in full sun in well-

drained soil. USE: Use in containers, hanging baskets, in informal drifts in borders or cottage gardens and as fresh or dried cut flowers.

Nullabar buttons (Chrysocephalum apiculatum), is a relatively new everlasting from Australia.

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Coreopsis, tickseed (Coreopsis spp.) Although marketed as a perennial, coreopsis is more honestly treated as an annual in colder areas of the prairies. In more protected locations, it occasionally overwinters or produces seedlings. Breeders have introduced an enormous number of cultivars in the last decade, greatly expanding the colour range of this cheerful, daisy-like plant and greatly increasing its popularity. The Greek word koris means bug, while opsis means like. As the common name tickseed suggests, the seed resembles an insect. Grandiflora means large-flowered. The flowers were once used for dying. Coreopsis grandiflora is native to the central and southern United States. These somewhat sprawling plants range in height from 20 to 90 cm (8–36 in.). The long-stemmed, single flowers are in bright shades of yellow, orange, brown, pink, purple or red, with some bicolour or banded cultivars. They are 2.5 to 5 cm (1–2 in.) in diameter, with notched or toothed petals. Coreopsis (Coreopsis grandiflora) sports lovely golden yellow daisies useful for beds, borders and cut flowers.

‘Early Sunrise’ has golden-yellow double flowers on compact plants 45 cm (18 in.) in height. ‘Heliot’ has single yellow flowers with burgundy centres on 25 to 36 cm (10–14 in.) plants. ‘Limerock Ruby’ has ruby flowers with yellow centres (40 cm/16 in.). ‘Rising Sun’ (45–60 cm/18–24 in.) blooms early with semidouble golden flowers, 5 cm (2 in.) in diameter, with a red splotch at the base of each petal. ‘Sunburst’ (60 cm/24 in.) has semi-double golden flowers. ‘Sweet Dreams,’ with dark burgundy centres, opens with petals a creamy white that mature to a bright raspberry pink. Plants are 50 cm (20 in.) in height and spread. Threadleaf coreopsis (Coreopsis verticillata) has a finer texture. It is native to the eastern United States and is very drought tolerant. A perennial in zone 4b (areas of southern Manitoba), it is treated as an annual in most prairie regions. ‘Moonbeam’ (45 cm/18 in.) has golden-yellow flowers and finely divided foliage.

Threadleaf coreopsis (C. verticillata) has a finer texture and is very drought tolerant.

‘Zagreb’ is the same height with soft yellow flowers and an extended bloom period. CARE: Coreopsis needs full sun and good drainage. It toler-

ates poor soil.

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USE: Place taller types on sunny banks and in waste spaces, naturalize in wildflower gardens or back lanes or use for massing or as cut flowers. Shorter cultivars may be used in beds and borders, as well as for edging.

Cosmos (Cosmos spp. )

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Another easy and satisfying drought-tolerant annual, cosmos was introduced from Mexico to Britain about 1800. Within the next century, breeders had selected brighter blooms and double flowers. Kosmos is the Greek word for beautiful and orderly (as our cosmos or universe is supposed to be). Native to regions near the equator, cosmos were originally “short-day” plants that would not set flower buds until the shorter days of autumn. By the 1930s, a “day-neutral” type called the Sensation strain (still available) had been developed that would flower in sufficient time to be of value in northern gardens. Most of our garden cultivars are derived from three species. Cosmos bipinnatus is generally 1 to 1.2 m (3–4 ft) in height. Bipinnatus refers to the attractive, finely divided, ferny foliage. This tall, old-fashioned annual produces single or double, daisy-like flowers, 8 to 10 cm (3–4 in.) in diameter, with yellow centres and pink, rose, red, violet, lavender or

Double Click mix of cosmos (Cosmos bipinnatus) has semi-double to double flowers in a mix of white, pink and rosy red.

white petals. It reaches its peak in summer and continues into fall. Cultivars include: Double Click mix produces semi-double and double flowers in a mix of white, pink and rosy red on 1.2 m (4 ft) plants. ‘Rubenza’ (90 cm/36 in.) is a dark ruby-red that fades to rose. Seashells mix is the same height but has unique flowers in pink, white and carmine with petals that are rolled and quilled. Sensation series has large (10 cm/4 in.) flowers in crimson, rose, pink or white on 1.2 to 1.5 m (4–5 ft) plants. Sonata series has large (6–8 cm/2.5–3 in.) flowers in carmine, pink, pink blush and white on compact (60 cm/ 24 in.) plants. ‘Sweet Sixteen’ (90 cm/36 in.) has soft pink flowers with a darker pink picotee edge. ‘Versailles Tetra Red’ is the same height with large (10 cm/ 4 in.) dark red flowers with a bright yellow eye.

Cosmos sulphureus is extremely floriferous (but perhaps not as drought tolerant as Cosmos bipinnatus) with flowers in orange, gold, yellow or scarlet.

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Chocolate cosmos (C. atrosanguineus) is shorter than other species (30–60 cm/24–36 in.), with single flowers in purple or red and a distinct chocolate fragrance. Yellow cosmos (C. sulphureus) is the same height but has broader foliage and produces semi-double flowers in orange, gold, yellow or scarlet. It is extremely floriferous but has a shorter blooming period and may require more water than the others. Cosmic mix has double flowers in great hot colours of yellow, orange and gold on 30 cm (12 in.) plants. CARE: Plant in full sun on poor, well-drained soils. Taller

types may require staking. Do not fertilize. Seeds are best sown directly. Pinch when the plants are young to encourage branching. It requires occasional deadheading. It is frost tender.

If you’re a chocolate lover, chocolate cosmos (C. atrosanguineus) with its distinct chocolate fragrance, should be your annual of choice!

USE: Plant taller cultivars in borders, cottage gardens or waste spaces. Use dwarf cultivars for edging. All may be used as cut flowers. Cosmos is a nectar source for bees and butterflies.

Chinese forget-me-not, hound’s tongue (Cynoglossum amabile) Even an inveterate dog lover like myself could guess which of the two common names would have more general public appeal. The genus name comes from the Greek words kyon, dog and glossa, tongue, referring to the texture and shape of the soft, hairy, grey-green leaves. Amabile means lovely and the flowers are! Native to southwest China, this biennial is grown as an annual. It produces a profusion of tiny, sky-blue flowers in airy sprays the first year from seed. It is at its best in early summer. The upright, bushy plants are 45 to 60 cm (18–24 in.) in height. Cultivars have blue, pink or white flowers. It’s ideal for pastel borders. Seed may be difficult to source. ‘Firmament’ is a dwarf cultivar of 36 cm (15 in.) with intense blue flowers. Introduced in 1939, it is still popular today. CARE: Grow in full sun or partial shade, in hot, dry locations. It

benefits from moderate deadheading as it will self-sow.

If you’re fond of the colour blue, try Chinese-forget-menot (Cynoglossum amabile), with its profusion of tiny, sky-blue flowers.

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USE: Use in mixed or annual borders, in cottage gardens or for naturalizing. It makes a dainty and fragrant cut flower and attracts butterflies.

Trumpet flower and angel’s trumpet (Datura spp.)

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A large and exotic annual long used in conservatories, Datura is a member of the nightshade family. All plants contain alkaloids that are poisonous, capable of causing hallucinations and even death. Datura is from the common name for this plant in India. Blooming from midsummer through autumn, the flowers generally open in the evening, remain open through the night and into morning and close in the afternoon – all this to accommodate the moths that pollinate them. Most varieties are derived from two species. Angel’s trumpet (Datura inoxia) is native to Mexico, Central America and the United States. This species reaches 90 cm (36 in.) with an equal or greater spread, with single or double flowers in white, yellow, pink or lavender. The flowers are fragrant, tubular and 18 to 20 cm (7–8 in.) in length. The large, sharply pointed leaves have wavy margins and are covered in soft hairs. Stems are purplish. The fruit is round, pendant and covered in thorns. ‘Black Currant Swirl’ has dark purple, frilly double flowers on 1.5 m (5 ft) plants. ‘Fleur Lilac’ is 30 to 45 cm (12–18 in.) and is blue lilac with

Angel’s trumpet (Datura inoxia), large and exotic looking with single or double flowers, is grown as a specimen plant or placed in annual or mixed borders.

a sweet fragrance. ‘Double Golden Queen’ has double, frilled, canary-yellow flowers (1.5 m/5 ft). Trumpet flower (D. metel) grows to 1.5 m (5 ft) and has large, smooth leaves and large, fragrant, trumpet-shaped flowers. Mostly white, the flowers are single or double. The inside of the flower is often pale violet. Metel is from the common name used in southwest China, to which it is native. Ballerina series includes soft shades of purple, yellow and white. Each 15 to 20 cm (6–8 in.) bloom has an intricate combination of petal-whorls that create a swirling effect. Plants are 90 to 120 cm (3–4 ft) high. It may self-seed. CARE: Grow in rich but well-drained soil in full sun. USE: Datura can be used as a specimen plant, in annual or mixed

borders, a white garden, in large containers or as an annual hedge.

Pinks, dianthus (Dianthus spp.) Another old-fashioned cottage garden favourite, pinks have been in cultivation in one form or another for at least two thousand years. The multitude of species includes annuals,

Trumpet flower (D. metal) are mostly white with a pale violet interior. All Datura species are poisonous.

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biennials and perennials. Because many of the annual cultivars are hybrids of various annual and perennial types, they may live one, two, three or four years, especially when snow cover is adequate. Most of today’s annual dianthus include parentage from Dianthus chinensis, D. barbatus and D. caryophyllus. From the Greek words dios, divine and anthos, of flowers, the genus name aptly describes the flowers’ beauty and fragrance. Dianthus are dwarf, compact, mounded plants of about 30 cm (12 in.) in height, with green or grey-blue, grassy foliage. The fragrant flowers are about 2.5 cm (1 in.) in diameter, with fringed petals in shades of white, red, pink, lilac or purple, with many bicolours. Amazon series have strong stems with good branching and green foliage and intense pink to purple flowers on 45 to 60 cm (18–24 in.) plants. Long blooming, the series includes ‘Neon Purple,’ ‘Neon Cherry’ and ‘Amazon Rose.’ Bouquet series has open lacy flowers in intense colours, including rose, purple and white, on well-branched plants of ‘Ideal Violet’ pinks (Dianthus hybrid) is well branched, 20 to 30 cm (8–12 in.) and covered in blooms.

45 cm (18 in.) with sturdy stems. ‘Bouquet Purple’ is a deep pink-purple. ‘Corona Cherry Magic’ is a bicolour with huge 6 to 8 cm (2.5–3 in.) blooms that combine solid cherry, lavender with a cherry centre and tie-dyed lavender/cherry on the same compact, 20 cm (8 in.) plant. Ideal series includes raspberry, red, rose, salmon, violet, white and bicolours. The well-branched, 20 to 30 cm (8–12 in.) plants are covered in blooms. ‘Merlot’ is a colour mix with extra large flowers on 20 to 25 cm (8–10 in.) plants. ‘Raspberry Parfait’ (20–30 cm/8–12 in.) is a bicolour of light pink with a raspberry centre. ‘Supra Purple’ (30 cm/12 in.) is an intense purple pink, highly fringed with a lacy appearance. CARE: Dianthus is tolerant of light frost and poor soil as long as it is well drained. Plant in full sun to light shade. Deadheading is beneficial. USE: Use as cut flowers, in borders, cottage gardens and as

‘Supra Purple’ (Dianthus hybrid) is an intense purple pink with a highly fringed, lacy appearance.

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mass plantings. The shorter cultivars are ideal for edging, containers and rock gardens. Place fragrant types within sniffing range to appreciate them fully. They are nectar plants for hummingbirds.

Livingstone daisy (Dorotheanthus bellidiformis, syn. Mesembryanthemum bellidiformis, M. criniflorum)

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This succulent, frost-tender plant from South Africa is yet another “African daisy” that has undergone a few name changes and may be found under various names in catalogues and on garden centre benches. Dr. Martin Schwantes named the genus after his mother, Dorothea. The species name, bellidiformis indicates its similarity to Bellis perennis, the English daisy, while the common name suggests the resemblance of its fleshy leaves to small stones. One of the early plant explorers, collecting in South Africa, did indeed pick up what he thought was a pebble and then realized it was a living plant. The livingstone daisy has lost popularity in recent years for no apparent reason. They have glimmering, daisy-like flowers, 2.5 to 5 cm (1–2 in.) in diameter, with narrow petals and dark centres. Petals can be crimson, white, pink, purple, yellow, buff, apricot or orange, often with a bicolour effect as they lighten toward the central disc. The flowers close when days are dull. Low and spreading, plants are 20 to 30 cm (8–12 in.) in height.

Native to South Africa, the fleshy leaves of the livingstone daisy (Dorotheanthus bellidiformis) resemble small stones.

Harlequin mix (15 cm/6 in.) comes in a wide range of colours, including bicolours, with a black eye. CARE: Plant in full sun on sandy, well-drained soils. Deadhead

to improve its appearance and prolong flowering. USE: They are ideal in hot, dry areas of a rock garden, as

edging and container plants. They are salt tolerant.

Tassel flower (Emilia coccinea, syn. E. javanica)

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Not often seen in gardens, the tassel flower may be difficult to obtain, but it is the most popular of the twenty species of Emilia. The Emilia honoured by the genus name remains unknown. This plant is native not only to Java (from which the older species name is derived) but to other parts of the tropics. The common name is very apt, as the bright orange-red or yellow flowers look very much like the tassels by which formal drapery is held. The tiny flowers are supported by wiry stems, 45 to 60 cm (18–24 in.) in height, above the grey-green leaves. Emilia javanica var. lutea has yellow flowers. CARE: It grows best in full sun on dry soil and may self-sow. USE: Plant in annual or mixed borders and use them as fresh or dried cut flowers.

The bright orange-red or yellow blooms of the tassel flower (Emilia coccinea) do indeed resemble the tassels which hold formal drapery.

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California poppy (Eschscholzia californica)

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Native to the dry hills of California, Oregon and into Washington, the species is mainly orange further inland, but a burnished yellow along the coast. It has naturalized in many parts of the world. The genus was named for Johann F. von Eschscholtz (1793–1831), a German physician, naturalist and botanist who collected plants in California, South America and the Pacific Islands. He discovered the California poppy in 1816 while part of a Russian expedition. It must have been an amazing sight to see the hillsides covered in such an intense and vibrant orange. The somewhat sprawling plants are 20 to 38 cm (8–15 in.) in height and spread, with finely dissected, grey-green or bluegreen leaves. The satiny, single or double, cup-shaped flowers are 5 to 8 cm (2–3 in.) in diameter, in white, lemon, gold, orange, salmon, cream, scarlet, mauve, rose, pink, purple or violet. Flowers have a long blooming period but close at night and during cloudy weather. Mission Bells is a mixture of semi-double scarlet, gold, cherry, orange and pink flowers on 40 cm (16 in.) plants. California poppies (Eschscholzia californica) are undemanding, bright and reseed with abandon.

Thai Silk mix (20 cm/8 in.) has double flowers in a wide range of colours and combinations. CARE: California poppies do not transplant well. Sow seeds

directly into well-drained soil in full sun to light shade. Do not fertilize. They tolerate light frost and will self-seed. USE: Use in wildflower or cottage gardens and for naturalizing.

Grassleaf spurge and snow-on-the-mountain (Euphorbia spp.) The genus was named after Euphorbus, physician to Juba, once king of Mauritania. He used the latex-like sap for medicinal purposes. The true flowers, called the cyanthia, are inconspicuous, but the bracts or modified leaves are extremely attractive. The milky latex sap is both poisonous and an irritant to eyes and skin. It is prudent to wear gloves while working with these plants and to avoid rubbing your eyes. One cultivar of Grassleaf spurge (Euphorbia graminea, syn. E. hypericifolia, Chamaesyce hypericiifolia) has proven to be an outstanding plant with understated charm. Related to A very recent introduction, ‘Diamond Frost’ grassleaf spurge (Euphorbia graminea) is an outstanding plant with understated charm.

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poinsettia, ‘Diamond Frost’ has been the recipient of many awards since it was released in 2005 and with good reason. The hundreds of minute, dainty white flowers (actually bracts) against the bright green leaves look bright but refined

and combine well with almost all other plants. As well, it blooms continually and requires little maintenance. Airy white flowers, somewhat resembling baby’s breath, are set against tiny grey-green leaves. The plant itself is mounding, up to 30 cm (12 in.) in height with a 30 to 60 cm (12–24 in.) spread. CARE: Heat- and drought-tolerant, it does best in full sun to

partial shade on well-drained soil. Old blooms fall off, so it requires no deadheading. It will decline in cool, wet soil. USE: Use as an annual ground cover, in containers and

hanging baskets or cascading over low walls. It can be overwintered as a houseplant. Snow-on-the-mountain (E. marginata)

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is definitely not

a weed, as some Euphorbia species are considered! While the best-known plant in this genus is the Christmas poinsettia (E. pulcherrima), snow-on-the-mountain is by far the most beloved annual and has been a dependable mainstay of rural prairie gardens for decades. It is both highly visible and highly attractive. The word marginata refers to the white margins on the upper leaves.

Snow-on-the-mountain (Euphorbia marginata), grown for its foliage with its distinctive white margins, has been a beloved part of rural prairie gardens for years.

Native to the southwestern United States, snow-on-themountain is about 60 cm (24 in.) in height, upright, with soft, grey-green foliage. The upper bracts (modified leaves) have white margins, while the topmost ones may be entirely white. ‘Summer Icicle’ is shorter than the species (45-60 cm/ 18–24 in.) but otherwise similar. CARE: Snow-on-the-mountain thrives in heat and poor soil.

Place it in full sun to light shade in well-drained soil. USE: Use it as a foil for brighter colours, as an accent plant in formal and cottage gardens, in containers and as foliage in arrangements. It is stunning in a white garden.

Annual gaillardia, blanket flower (Gaillardia pulchella) Gaillardia is as easy to love as it is easy to grow and care for. It asks little of the gardener and gives much in return. Many of the modern hybrids have both annual (Gaillardia pulchella) and perennial (G. aristata) parentage and are now classified as G. grandiflora. They may keep you company longer than a single season. Some are introduced as annuals and others as perennials. Their longevity will vary from one part of the prairies to another and is also dependent on the severity of winter

‘Mesa Yellow’ blanket flower (Gaillardia grandiflora) produces yellow flowers over a long period on plants 40 to 45 cm (14–16 in.) high.

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temperatures and the presence or absence of insulating snow cover. While the genus was named to honour a French patron of botany, M. Gaillard de Charentonneau, puchella simply means pretty. Native to North America, blanket flowers produce single or double, daisy-like flowers about 5 cm (2 in.) in diameter in an autumnal array of colours: yellow, orange, red, brown and bicolours with purple centres. The leaves, sometimes lobed or toothed, are a dull green and attached directly to the stems without leaf stalks. The plants are 45 to 60 cm (18–24 in.) in height, upright and bushy. ‘Mesa Yellow’ produces uniform plants with large (8 cm/3 in.) yellow flowers over a long period on 40 to 45 cm (16–18 in.) stems. ‘Red Plume’ bears large (5 cm/2 in.), double, dark brick red flowers on compact plants of 36 to 40 cm (14–16 in.). ‘Sundance Bicolor’ has double, mahogany-red and yellow bicolour flowers and is 25 to 35 cm (10–14 in.) high. ‘Sundance Bicolor’ is a relatively new blanket flower (G. grandiflora) with double, mahogany-red and yellow flowers.

CARE: Plant in full sun on a range of well-drained soils. While

the species and the older varieties were extremely drought tolerant, some of the newer ones are only moderately so. USE: They are excellent in beds, borders, cottage gardens, containers, for naturalizing on dry banks or back lanes, as cut flowers and a must in “hot” gardens.

Gazania (Gazania rigens)

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Another popular South African daisy, gazania is perhaps a little more easily identified than some of the others: the base of the “petals” (the ray flowers) is generally dark, forming a ring around the golden central disc. Another clue for the botanically inclined: gazania ray flowers are fused at the base; those of Arctotis are separate. The genus name honours Theodore of Gaza (1398–1478 A.D.), who translated the botanical works of Theophrastus from Greek to Latin. Rigens means rigid and may refer to the stout bracts below the flowers. Gazania has satiny, single flowers, 5 to 8 cm (2–3 in.) in diameter, in glowing shades of yellow, orange, bronze, pink or white. With satiny single flowers and a dark centre, gazinia (Gazinia rigens) is available in shades of yellow, orange, bronze, pink or white.

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They are borne singly on 10 to 15 cm (4–6 in.) stems, closing at night and on cloudy days. The dark green leaves are thick but narrow with white undersides and rise from basal rosettes. Plants are 15 to 30 cm (6–12 in.) in height.

Big Kiss series produces large (12 cm/4.5 in.) flowers in yellow or white, each with dark pink stripes, on 20 cm (8 in.) plants. Daybreak series includes ten intense colours on 20 cm (8 in.) plants. Talent mix has unique silver-green (almost white) foliage in several colours on dwarf, 20 cm (8 in.) plants. CARE: Grow in well-drained soil in full sun. It is wind-tolerant

but frost-tender. USE: Gazania are useful as bedding plants, in borders, massed, in rock gardens, as edging and in containers. A perennial in its native habitat, it can be brought indoors as a winter houseplant.

Globe amaranth (Gomphrena globosa)

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This old-fashioned annual is no longer as popular as it once was, yet the modern hot pinks are to die for. Globosa describes the egg-shaped flowers; Gomphrena is from the Latin common name for this plant. Native to the tropics of both India and Central

‘Talent Orange’ gazinia (G. rigens), available in several colours on dwarf plants, has unique silver green, almost white, foliage.

America, it is closely related to Celosia and Amaranth, but the flowers are on a much smaller scale. The bushy, upright plants generally range in height from 15 to 75 cm (6–30 in.) but can be up to 1 m (3 ft). The almost iridescent, clover-like flowers are in white, yellow, orange, salmon, pink, rose, red, purple or bicolours. The oblong leaves are pointed and pubescent. The stems have swollen nodes. ‘Bicolor Rose’ (60 cm/24 in.) has rose-pink flower heads. ‘Fireworks’ sports masses of pink toothpick-like petals with cream tips and is 90 to 120 cm (36–48 in.) in height. Gnome mix includes pink, white, purple and rose flowers on dwarf plants of 15 to 20 cm (6–8 in.). QIS series produces bushy, 60 cm (24 in.) high plants in purple, pink and white. ‘Strawberry Fields’ (60 cm/24 in.) has true red flowers on vigorous plants. CARE: Plant in full sun in well-drained soils. It is wind-tolerant. USE: Excellent as bedding plants, in borders, rock gardens,

cottage gardens, containers, as edging and in fresh or dried arrangements. The flowers retain their colour for a long time.

The newer pink cultivars of globe amaranth (Gomphrena globosa) are amazing and intense. Used in fresh or dried arrangements, they retain their colour for a long time.

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Annual baby’s breath (Gypsophila elegans) It’s not hard to believe that a plant with such a delicate, misty, airy appearance has been a mainstay of our gardens for centuries. The genus name, from the Greek words gypsos, gypsum and phlios, lover of, indicates its preference for alkaline or lime soils (predominant on the prairies). Elegans means elegant, an apt description. The common name alludes to its sweet fragrance. Native to Europe and Asia, this old-fashioned annual is 45 to 60 cm (18–24 in.) in height and much branched. The masses of tiny white, pink or rose flowers are produced on wiry stems above small, dark green, narrow leaves. It flowers for six weeks. ‘Covent Garden’ (‘London Market’) bears large, white, single flowers on 60 to 75 cm (24–30 in.) plants. Gypsy series has myriads of single pink, rose and deep rose With a delicate, misty, airy appearance, annual baby’s breath (Gypsophila repens) has been in gardens for centuries.

flowers on plants of 30 to 35 cm (12–14 in.). CARE: Plant in full sun on well-drained soil. Successive

plantings ensure continuous bloom. USE: Ideal in fresh and dried arrangements, it is also useful in

borders (as a filler where other plants have died out or finished blooming), in cottage gardens and in containers.

Sunflower (Helianthus annuus) For years, we drove past fields of annual sunflowers destined for oil or “spits” and marvelled at their height and ability to “follow the sun.” We occasionally planted them in rural vegetable gardens as windbreaks, as living birdfeeders or simply as a burst of colour. Things changed in the 1990s. Suddenly, sunflowers were “in.” New hybrids with vibrant colours, shorter stature and often pollen-less (no mess or staining but nor do they produce seed or attract birds) took the gardening world by storm. And it hasn’t stopped yet. There is a plethora of cultivars! Europe seems to have a greater appreciation for them than we do here in North America and if you really want to see sunflowers in their glory, visit Claude Monet’s garden in Sunflowers (Helianthus annuus), once confined to rural gardens, are now “in” and available in a wide range of colours and sizes. Many are pollenless and excellent for arrangements.

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Giverny, France in late summer or fall. Helios is the Greek word for sun, anthos for flower. The large, yellow flowers resemble the sun and turn to follow it through the day. The edible seeds have long been used by the Indigenous peoples of North America, to which it is native. The common sunflower, ranging from 2 to 3 m (6–9 ft) or more in height, has huge yellow flowers. Newer cultivars are

shorter, often branched and in colours from white through yellow, orange, bronze, mahogany, purple and red, including bicolours and single and double forms. They begin blooming in late summer and continue into fall. The leaves are large, rough and hairy. These usually have stronger stems and lighter heads and are useful as cut flowers. Pollenless cultivars: ‘Moulin Rogue’ (2 m/6 ft in height) has 10 cm (4 in.) blooms in red with a dark central disk. ‘Soraya’ is a multi-branching plant of 1.5 m (5 ft) with over twenty large (10–15 cm/4–6 in.), bright tangerineorange flowers. Seed-bearing cultivars: Autumn Beauty mix bears 10 cm (4 in.) single flowers in yellow, bronze, red and purple on 1.5 to 1.8 m (5–6 ft) plants. ‘Italian White’ (1.8 m/6 ft) has 10 cm (4 in.) ivory white to primrose flowers with a brown centre. Pacino mix has single flowers in lemon yellow or gold with green to brown centres on bushy, well-branched plants of 40 cm (16 in.).

‘Goldie’ is a bright golden yellow, double sunflower (H. annuus) with multiple heads on 1.6 to 2 m/5–6 ft stems.

‘Ring of Fire’ (1.2 m/4 ft) has 15 cm (6 in.) single flowers in mahogany with a gold centre. ‘Russian Giant’ (‘Mammoth Russian’) is perhaps the tallest of all (3 m/10 ft or higher), with enormous single yellow heads. ‘Teddy Bear’ is a dwarf variety of 1 m (3 ft) with double golden-yellow heads. ‘Valentine’ has 15 cm (6 in.), pale yellow flowers with a rich brown centre on multi-branching plants of 1.2 m (4 ft). CARE: Plant in full sun to partial shade in a range of soils. Sow

seeds directly. Taller cultivars benefit from a single moderate application of a well-balanced fertilizer. USE: These are excellent as accent plants, for screening, in

mixed or annual beds and in fresh or dried arrangements. Use dwarf cultivars in containers. Go for the gold and plant them in masses with drifts of different cultivars. Cheap, quick and so effective!

The colour range of sunflowers has expanded to include white, yellow, gold, orange, bronze, red and purple.

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Dusty miller (Jacobaea maritima, syn. Senecio cineraria, Cineraria maritima)

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Dusty miller is a common name applied to several genera. This particular dusty miller has had three name changes in the past few decades and plants may still be found under all of them in garden centres and catalogues. This can confuse novice and experienced gardeners alike, but go for the plant that appeals to you! A tender sub-shrub grown as an annual, all parts are poisonous to both people and livestock. The older genus name, Senecio, is from the Latin word for old man, an apt description of the fluffy white seed heads (which are not always seen in our short growing season). The older species name, cineraria, is Latin for ashen grey, a reference to the leaf colour, as is the common name. Jacobaea may honour St. James (Jacobus), while maritima means of the sea, close to its native habitat. Native to southern Europe and the Mediterranean, dusty miller is grown for its deeply cut, heavily pubescent silver foliage. Plants range in height from 20 to 30 cm (8–12 in.). This species of dusty miller (Jacobea maritima) is noted for its deeply cut, heavily pubescent foliage.

‘Cirrus’ (15–20 cm/6–8 in.) has broad, silvery-green, shallowly lobed foliage. ‘New Look’ (30 cm/12 in.) has broad, felt-like, greenish-grey leaves that are shallowly lobed. ‘Silver Dust’ (25 cm/10 in.) has deeply incised, velvet-like, silver leaves with a lacy appearance. CARE: Grow in full sun or partial shade on ordinary, well-

drained soil. Pinch young plants to encourage bushiness. USE: Plant in borders, containers, cottage gardens and as edg-

ing. Try planting these informally in drifts in a mixed border rather than in concentric circles with begonias as the Victorian gardeners, with their penchant for extreme formality, were wont to do. They are useful for separating stronger clashing colours and look very pretty combined with pink or blue flowers in a pastel border.

Lantana (Lantana hybrida, syn. L. camara hybrida)

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Trailing lantana is a perennial that was used as a conservatory and greenhouse plant during the Victorian era. Native to Uruguay and other areas of South America, it has become widely naturalized in the tropics and the southern United Trailing lantana (Lantana hybrida) is ideal in containers or as a winter houseplant.

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States (where in some areas it is considered a weed), but it has recently found a new life as an outdoor “annual” in the more temperate areas of North America. Some of the newer

cultivars are from the species Lantana camara or are hybrids with L. camara as part of their parentage. The small clusters of white, lavender, pink, orange, yellow or rosy-lilac flowers with white centres are formed in rounded heads on trailing stems. With a height of 60 to 90 cm (24–36 in.), the foliage is dark green and hairy. When crushed, some varieties give off an unpleasant smell, while others have a nice lemony fragrance. Newer cultivars change colour as they mature, giving plants a bicolour effect and adding interest. Luscious Citrus blend (60 to 90 cm/2–3 ft) has flowers in red, orange and yellow with fragrant citrus-like foliage. Lucky series is a heavy bloomer with flowers in rose, honey blush, lemon cream, peach and yellow on compact plants of 30 to 40 cm (12–16 in.). ‘Pink Caprice’ (60 cm/24 in.) has pale yellow buds that mature to pink flowers, giving it a two-tone effect. CARE: Plant in full sun. Although frost-tender, they are wind-,

salt- and drought-tolerant. They do best when summers are hot. Use caution, however, if you decide to grow this plant. It is poisonous if eaten and the foliage is toxic to both livestock and pets. USE: Use in containers and as winter houseplants.

Statice, sea lavender (Limonium sinuatum)

Luscious Citrus blend, a new lantana (Lantana hybrida) introduction, has flowers in red, orange and yellow and fragrant citrus-like foliage.

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In Europe, statice is grown primarily for the florist trade. It’s also a wonderful addition to a mixed border, easy to grow and quite different in form from most everlastings which are daisy-like. A perennial in Eurasia, it is treated as an annual on the prairies. Limonium, from the Greek leimon (meadow), alludes to its native habitat near salt flats along the coast of the Mediterranean. Sinuatum means wavy margin and describes the leaves. Although the species has yellow flowers, cultivars are in white, yellow, pink, blue or purple, usually with white centres, flowering from midsummer through fall. Sea lavender produces masses of crescent-shaped flower heads, each consisting of tiny, funnel-shaped, papery florets. Plants are about 75 cm (30 in.) in height with a spread of 60 cm (24 in.). The lance-shaped leaves are basal and pinnately divided and the stems have a winged protrusion and appear triangular in cross-section. Pacific series includes rose, apricot, yellow, blue, white and pink on uniform plants of 60 to 75 cm (24–30 in.).

Native to salt flats of the Mediterranean coast, statice or sea lavender (Limonium sinuatum) is available in white, yellow, pink, blue or purple

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QIS mix (75–90 cm/30–36 in.) is available in dark blue, pale blue, rose, white and yellow. CARE: Heat- and salt-tolerant, sea lavender does well in a fer-

tile but well-drained sandy or loamy soil in full sun. USE: Attractive massed in the border, they are excellent as dried or fresh-cut flowers and are a nectar plant for butterflies.

Sweet alyssum (Lobularia maritima, syn. Alyssum maritimum) An old-time favourite, sweet alyssum is a member of the mustard family, as is canola. Although both may be attacked by flea beetles, their resemblance ends there. Their fragrances are altogether different, one sweet, the other not so. Native to southern Europe and the Mediterranean region, alyssum is widely naturalized on sandy soils in other areas of Europe. Plant breeders have worked hard to give it greater heat tolerance so it doesn’t fade out in midLow and mounded, sweet alyssum (Lobularia maritima), with it’s white, pink, purple and rose flowers, is useful for edging and borders.

summer as it once did. The genus name is derived from the Latin lobulus, a small pod (describing the seed), while maritima means growing near the sea, its native habitat. The common name, alyssum, is derived from the Greek a, meaning not and lyssa, meaning madness. It was once believed to cure rabies. The plants are low (10–20 cm/4–8 in.) and mounded, with a 30 cm (12 in.) spread, blooming profusely from spring to midsummer, with less flowering in the heat of July and August. Flowering resumes with cooler weather. Extremely fragrant, the tiny, fourpetaled flowers are formed in compact racemes and are available in white, purple, rose, pink, lavender and apricot. Leaves are small, narrow and silver-green. Watch for new vegetative cultivars. Clear Crystal series has extra-large flowers in white, lavender and purple on vigorous, heat-tolerant, mounded plants of 10 cm (4 in.). Easter Bonnet series includes deep pink, deep rose, lavender, white and violet flowers on 10 to 25 cm (4–10 in.) plants that are early and uniform. ‘Rosie O’ Day’ is a light rose pink with a white centre, 15 cm (6 in.) high. ‘Royal Carpet’ (10 cm/4 in.) is a violet purple. ‘Snow Crystals’ has large, fragrant, white flowers on mound-

New breeding developments have assured better heat tolerance in sweet alyssum (L. maritima) as well as a greater range of colours.

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ed, 30 to 35 cm (12–15 in.) plants. Wonderland series boosts good heat tolerance and earliness with deep rose, pink, purple, cream, yellow, lavender and white flowers on dwarf, compact plants of 7 cm (3 in.).

CARE: Coming from the seacoast, they tolerate wind and salt.

Plant in full sun to partial shade in well-drained soil. They need adequate moisture for development and are then drought tolerant. USE: Use for edging, massing, with spring bulbs, in rock gar-

dens, containers, borders and in pavement plantings among the flagstones of a walk. Place them near a patio, porch or deck where you can enjoy the fragrance.

Iceplant (Mesembryanthemum crystallinum, syn. Cryophytum crystallinum)

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With a low stature and distinctive foliage, it doesn’t matter if it’s from South Africa and has daisy-like flowers. Iceplant is memorable! The genus name, Mesembryanthemum, is from the Greek phrase for midday – the flowers open only on sunny days. The species name, crystallinum, means crystalline and refers to the ice-like specks on the foliage due to the presence of small transparent bladders that look like frozen dew. The common name

The unusual ice-like specks on the foliage give iceplant (Mesembryanthemum crystallinum) both its common and species names.

also describes the leaves. Grown as much for its foliage as its blooms, iceplant has succulent leaves and a prostrate form. The shimmering, 8 cm (3 in.) daisy-like flowers are in yellow, pink, red, lavender or white, held on 15 cm (6 in.) stems. ‘Lunette’ (38 cm/15 in.) is an M. occulatum selection with bright lemon-yellow flowers with a rosy-red centre. CARE: Grow in full sun in light, well-drained soils. Despite its

common name, it flourishes in heat and will not stand frost. Many look poorly in garden centres due to overwatering. Treat them to nutrient poor, dry soil and they’ll thrive. USE: Excellent for hot, windy areas, it is used in containers, as edging and in rock gardens.

Hybrid flowering tobacco (Nicotiana sanderae ) Of the several species of flowering tobacco available to prairie gardeners, this is the most drought tolerant. Native to South America, it is treated as an annual on the prairies. The flowers attract butterflies as well as hummingbirds at both ends of their long migration. They begin flowering in mid to late summer and continue until hard frost. Like their addictive relative, all parts are poisonous. The genus is named for John Nicot (1530–1600), who introduced tobacco to France. These hybrids are a cross of N. alata x N. forgetiana. They are

‘Perfume Deep Purple’ hybrid flowering tobacco (Nicotiana sanderae) was selected for its evening fragrance and long bloom period.

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generally 30–90 cm/12–36 in. high, available in red, pink, purple, green and white and give off an evening fragrance. Avalon series, dwarf compact plants of 20 to 30 cm (8–12 in.), includes ‘Avalon Lime,’ ‘Purple Bicolour’ and ‘Pink Picotee.’ Nicki mix (35–40 cm/14–16 in.) produces well-branched plants in red, white, pink and purple. Perfume series is the same height as Nicki mix, in white, bright rose, red, deep purple, blue, lime and antique lime. They were selected for their evening fragrance and long bloom period. Saratoga series has a range of colours on uniform plants of 25 to 30 cm (10–12 in.). CARE: Place in full sun to partial shade. The strong stems sel-

dom need staking. Plants may self-seed. USE: Plant in a border or near a porch or patio to enjoy the Part of the Avalon series, ‘Appleblossom’ (N. sanderae) has lovely white flowers with a pink tinge on dwarf compact plants of only 20 to 30 cm (8–12 in.).

fragrance. They make a good cut flower. The white and limeyellow types are wonderful in a night garden both for their colour and fragrance.

Chilean bellflower (Nolana paradoxa)

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Resembling a cross between a petunia and a morning glory, Chilean bellflowers are tougher than they look. Nolana means little bell in Latin and describes the flowers. The species name, paradoxa, means unusual. Native to Chile and Peru, these are prostrate, ground-hugging and trailing plants of about 15 cm (6 in.) with fleshy leaves. The dark blue, white, purple or violet flowers are tubular, upward-facing, 5 cm (2 in.) in diameter, with ruffled petals, a white centre and a yellow throat. The flowers close on dull days. The oval leaves are opposite and a bit sticky. ‘Sky Blue’ trailing bellflower (N. humifusa) has flowers with a contrasting white throat on dwarf, 10 cm (4 in.) plants.

Chilean bellflfower (Nolana paradoxa) is a groundhugging, trailing annual ideal for containers or tumbling over a wall.

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CARE: Plant in full sun to partial shade, in well-drained soil. Due to their long taproot, they may not transplant well. Sow directly or in biodegradable peat pots for transplanting. They are wind-tolerant, adaptable to different soils and exposures and tolerate moist or dry soil. Deadhead for more continuous bloom. USE: Chilean bellflower is a good summer ground cover on poor soils. Use it to cover a bare bank or in a rock garden, tumbling over a wall, as edging, or in containers.

African daisy (Osteospermum ecklonis, syn. Dimorphotheca sinuata)

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If confessions are in order, although I am awed by their beauty, I’ve never really been able to differentiate among some of these South African and Australian daisies. The same common name, African daisy, is given to several similar annuals. Adding to the mix-up is the fact that some species that used to be in the genus Dimorphoteca have now been transferred to Osteospermum. These plants are sold under both names in catalogues. Do I feel justified in not having been able to tell them apart for decades? Well, yes! Perennials in their native South Africa (but capable of flowering their first year from seed), they are, once again, treated as annuals on the prairies. They have shimmering, daisy-like flowers, 10 cm (4 in.) in diameter, with white, cream, yellow, orange or salmon petals and darker, purplish centres. Breeders are now overcoming this plant’s habit of closing at dusk and during cloudy or rainy weather. Plants are about 30 cm (12 in.) in height with a slightly wider spread and narrow leaves. Although they are somewhat sprawling, our eyes are drawn only to the flowers. Asti series has large (5 cm/2 in.) flowers in purple, lavender and white with blue centres on 30 to 45 cm (12–18 in.) plants. White is available separately and would glow in a white garden. ‘Osteo Voltage Yellow’ is early and long-blooming with vibrant colour and is very highly rated. A mounding plant of

African daisies (now Osteospermum, but still known to many gardeners as Dimorpotheca) have really come into their own in the last decade.

30 to 40 cm (12–16 in.), it spreads to 60 cm (24 in.). Passion mix includes 5 cm (2 in.) blooms in pink, rose, purple and white on 30 to 45 cm (12–18 in.) plants. Sunny series includes, among others, ‘Erica,’ a pinky purple; ‘Olivia,’ a strong pink; ‘Gwen,’ bright yellow; and ‘Sheila,’ a dusky pink and orange. Heights vary from 30 to 90 cm (12–36 in.). CARE: Grow in full sun in hot, dry, well-drained soil. Vegetative

types, grown from cuttings, need even moisture for good flowering. Deadhead to prolong bloom. USE: They are excellent in containers, massed, as fillers in a mixed border or in rock gardens.

Poppy (Papaver spp.)

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Poppies are a large genus of annuals and perennials among which are ornamental plants, edible species used in baking and those used legally in the pharmaceutical industry and illegally in the drug trade. Papaver, the Latin name for poppy, is derived

‘Asti White’ African daisy (O. eckionis) has large flowers with blue centres and is ideal for a white garden.

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from the word pap, meaning milk, a reference to the milky sap. Their buds are nodding and their leaves are lobed or dissected. Most perpetuate themselves through reseeding. Iceland poppy (Papaver nudicaule) is circumpolar, native to Arctic and subarctic regions of Europe, Asia and North America. Nudicaule means a bare or nude stalk; there are no leaves present on the wiry flower stems. Biennial in habit, they produce dainty, tissue-papery flowers throughout the summer in vibrant shades of orange, yellow, white, cream and salmon pink. The flowers are up to 7.5 cm (3 in.) in diameter and held 30 to 45 cm (12–18 in.) above the basal rosette of finely divided foliage. Champagne Bubbles mix, with a height and spread of 38 by 15 cm (15 x 6 in.), has large flowers in multiple colours. Flamenco series comes in pastel shades with contrasting picotee edges. Iceland poppies (Papaver nudicaule), biennial in habit, have dainty tissue paper-like flowers in vibrant shades of orange, yellow, white, cream and salmon pink.

‘Solar Fire’ has bright orange flowers with yellow centres. CARE: Plant in full sun on well-drained soils. Do not mulch so

as to encourage self-seeding. Plants are short-lived but selfseed, although not always true to the parent plants. USE: Iceland poppies are valuable in the border and rock garden and for naturalizing because of their extended period of bloom. The decorative seed capsules are used in dried arrangements. Corn poppy, Flanders poppy, Shirley poppy (P. rhoeas) is the poppy of John McCrae’s poem “In Flander’s Fields.” Native to Europe, North Africa and Asia, it flowers in spring and summer. The species name, rhoeas, is from the Greek rhodo, rosecoloured, alluding to their use as a red dye in ancient times. Up to 1 m (3 ft) in height, its silky flowers are single or double, in pink, purple, red, white, salmon, orange, yellow, apricot or bicolours and about 5 to 7 cm (2–3 in.) in diameter. The foliage is dark green, hairy and roughly toothed. The Shirley poppy, a strain of Papaver rhoeas selected by the Reverend Wilks of Shirley, England in the 1880s, was developed from a single plant with a very narrow edge of white. This eventually led to the single and double flowers

‘Falling in Love’ is a mixture of single and double Shirley poppies (P. rhoeas) in pink, red, and coral, including bicolours, with many edged in white.

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we know today in white, pink or red with a white blotch at the base of each petal. Seed strains of the Shirley poppy are still available. ‘Falling in Love’ has large (8 cm/3 in.), silky flowers in a

mixture of semi-double and doubles in all shades of red (carmine, crimson, scarlet and rose) as well as coral, pink and white in solids and bicolours on plants 30 to 45 cm (12–18 in.) in height. ‘Ladybird’ (P. commutatum) is the British term for ladybug and fits these glossy blooms of bright crimson with black blotches. The single flowers are 8 cm (3 in.) in diameter on long wiry stems of 45 cm (18 in.). CARE: Plant in full sun in well-drained soil. Deadhead for lon-

ger flowering, leaving some seed pods to self-sow for the coming year. USE: Use in roadside plantings, cottage gardens and annual or mixed borders.

Geranium (Pelargonium x spp.) Native to South Africa, geraniums were first introduced to

‘Ladybird’ poppy (P. commutatum) is bright crimson with black blotches, resembling a ladybug.

England in the 1690s. They were extremely popular on windowsills and in parlors during the long reign of Queen Victoria and are today omnipresent in the window boxes of Europe and among the most planted annuals in North America. In East Africa, where they are perennial and reach heights of 2 m (6 ft), they are commonly used as hedges – a lot classier than caragana! The Greek word pelargos means stork, alluding to the seed’s resemblance to a stork’s bill. The species name, hortorum, means of the garden. Colours include white, pink, rose, red, orange, salmon and some bicolours. Cultivars are generally 30 to 60 cm (12–24 in.) in height with a spread of 30 cm (12 in.). The rounded, scented leaves are often attractively “zoned” with darker or lighter bands of colour. Newer cultivars tend to hold their petals better in the wind. Black Velvet series (30 to 45 cm/12–15 in.) is noted for its almost black foliage colour with a green rim. Flower colours include apple blossom, red, rose and salmon. ‘Crystal Palace Gem’ was first introduced in England in 1869 and named for Joseph Paxton’s elaborate glass house. It has round chartreuse leaves with a mid-green centre, salmon-red flowers and is 45 cm (18 in.) in height. Daredevil series boasts large, vigorous plants of 60 cm (24 in.) in salmon, orange-red, white and pink. Elite series is early and has zonal foliage on 30 to 35 cm (12–14 in.) plants, producing 10 cm (4 in.) blooms in six colours.

One of the most popular annuals in North America and Europe, geraniums (Pelargonium spp.) are perennials in their native South Africa and can be overwintered indoors on the prairies.

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‘Indiana Dunes’ (25 cm/10 in.) has deep orange flowers above attractive, bright chartreuse leaves that are marked with a reddish-brown splotch. Maverick series has multiple 40 to 45 cm (16–18 in.) stems and is available in coral, pink, red, salmon, scarlet, violet, white and a bicolour. Multibloom series has a multitude of colours on multiple flower stems of 25 to 30 cm (10–12 in.). ‘Orange Appeal’ is an excellent tangerine red with good branching on 30 to 45 cm (12–15 in.) plants. Orbit series includes seventeen flower colours on compact, branching plants of 30 to 38 cm (12–15 in.) with zonal leaves. Pinto series has eleven colours with good leaf zonation on ‘Orange Ice’ of the Divas series is a free flowering, unique bicolour of pale orange and white, 30–35 cm (12–14 in.) in height.

30 to 35 cm (12–14 in.) plants. ‘Vancouver Centennial’ (30 cm/12 in.) has outstanding foliage. The leaves are the shape of a maple leaf with a rusty-red centre and a lime-green edge. The reddishorange flowers are a standout. Ivy geraniums (Pelargonium peltatum) have single flowers in a vast array of colours and ivy-shaped leaves on long, trailing stems. They are used extensively in hanging baskets and do better when afternoon shade is provided. Cascade series is one of the most drought-tolerant for containers. There are many colours. ‘Sofie Cascade’ has light salmon-pink single flowers and is 30 to 45 cm (12–18 in.) in height. Summer Showers series has a trailing habit and 10 to 12 cm (4–5 in.) flower heads in a range of colours on plants of 30 to 35 cm (12–15 in.). CARE: Geraniums need both good fertility and good drainage.

Plant in full sun in fertile, loamy soil to which organic matter has been added. Overwatering may result in stem rot and edema, which causes brown, corky thickenings on the leaves. Spent flowers should be removed to improve the appearance of the plants and promote continuous bloom. USE: Geraniums are used for annual beds, mixed borders, conIvy geraniums (Pelargonium peltatum) are especially valued for containers and hanging baskets.

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tainers, hanging baskets and as houseplants through winter. They are a nectar source for hummingbirds.

Perilla, beefsteak plant (Perilla frutescens var. crispa, syn. P. ocymoides)

Known as beefsteak plant (due to a perceived resemblance of its foliage), the ‘Crispa’ of the botanical name enhances the meaty image. Perhaps it’s better to stick to perilla, from the Hindu name for this plant. Frutescens means shrubby, a reference to its form in its native habitat in India, China and Japan. Interestingly, the oil from the nutlike seeds is used in the manufacture of paints and varnishes. It has long been a source of dye and flavouring in Asian dishes, but is toxic to livestock. A member of the mint family, with square stems and opposite leaves, perilla is grown for its remarkable basil-like foliage: reddish purple, metallic, wrinkled and cinnamon-scented. It is generally about 60 cm (24 in.) in height but can grow taller and resembles coleus, to which it is related. The white to pink, twolipped flowers are insignificant and should be mostly pinched so as not to detract from the foliage and to prevent too many unwanted seedlings. ‘Magilla’ has deep pink-and-burgundy foliage on 1 m (3 ft) plants. CARE: Grow in full sun to very light shade in average, well-

Perilla or beefsteak plant (Perilla frutescens) is grown for its remarkable, basil-like foliage – reddish purple, metallic, wrinkled and cinnamon-scented.

drained soil. It is grown from cuttings or seed, but the seed is not easy to obtain. It will reseed. It does best during hot summers. USE: Use in mixed borders, for annual beds, large contain-

ers and as a houseplant. The dark foliage makes an excellent background for pastel pinks, yellows and blues.

Petunia (Petunia x hybrida) Petunias hardly need an introduction. One of the most popular annuals in North America, petunias are dependable, long-blooming and fragrant, but perhaps overused. Once common in Victorian bedding-out schemes, they have more recently been developed as bushy mounding or trailing plants in hanging baskets, window boxes and other containers. Although drought tolerant, there are fewer flowers when it is too dry. Petun is an aboriginal Brazilian name for tobacco, to which petunias are related. (Both are members of the nightshade family.) Native to the pampas of Argentina, where they are perennial, they were introduced to Europe in the mid-1800s. There are hundreds of cultivars, in red, pink, purple, blue, white and yellow. As well, there are bicolours, ruffled and striped forms, singles and doubles. Heights range from 15 to 38 cm (6–15 in.). It

Native to Brazil, petunias (Petunia x hybrida) are among the most popular North American bedding plants. ‘Ultra Crimson Star’ has large single blooms.

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boggles the mind to make a selection. To borrow an expression from a Belgian friend, there is indeed an “indigestion” of cultivars! Aladdin series contains many colours. It is early blooming, weather-resistant, with large, wavy, 8 cm (3 in.) blooms on 30 cm (12 in.) plants. Avalanche series has various colours and is one of the most floriferous of the spreading types. The weather-resistant plants are 20 cm (8 in.) high with a spread of 60 cm (24 in.). Cascade series, another spreading type, is 35 cm (15 in.) high and is available in a number of colours. The large, 10 cm (5 in.) flowers have wavy edges. Celebrity series is compact, with a mounded, 30 cm (12 in.) form and is early blooming, boasting 8 cm (3 in.) flowers of many colours. ‘Blue Daddy’ has large, 10 cm (4 in.) flowers of silver-blue ‘Pink Dawn’ (P. x hybrida), part of the Easy Wave series, is early and long blooming with a mounded form.

with violet veins on 25 to 30 cm (10–12 in.) plants with super garden performance. Easy Wave series is early and long blooming with a wide colour range and a mounded form, 15 to 20 cm (6–8 in.) high with a 60 to 90 cm (24–36 in.) spread. ‘Opera Supreme Pink Morn,’ in pinks and whites, is a robust, early, spreading type that is very floriferous and long blooming. Plants are 10 to 15 cm (4–6 in.) high with a spread of 60 cm (24 in.). Picobella series, in various colours, has a profusion of small blooms covering spreading, 20 to 25 cm (8–10 in.) plants that are vigorous and weather resistant. Primetime series has large, 7 cm (3 in.), single blooms in an enormous colour range. The 30 cm (12 in.) plants are weather resistant. Prism series has single flowers in various colours on 20 to 35 cm (10–14 in.) plants. ‘Prism Sunshine’ is a rich, nonfading yellow. Shock Wave series is trailing, spreading and mounding like the Wave series, but its vigour is “shocking.” The series is

‘Coconut’ (P. x hybrida) is part of the Shock Wave series. Trailing, spreading, mounding and with “shocking” vigour, it is early, prolific, self-cleaning and weather-resistant.

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early, prolific, self-cleaning, weather resistant and covered in masses of small flowers in many colours. Plants are 20 to 25 cm (8–10 in.) high with a spread of 30 to 60 cm (12–24 in.). ‘Soleil Purple’ was selected primarily for its great drought tolerance. It has masses of semi-double purple blooms

over an extended period, is compact and mounding, with a height of 25 to 30 cm (10–12 in.) and a spread of 60 to 90 cm (24–36 in.). Storm series produces long-flowering, very large, ruffled, single flowers in salmon, pink, white and lavender. Plants are weather tolerant, compact (25–30 cm/10–12 in.) and well branched. Supertunias are only 15 to 25 cm (6–10 in.) high, but can trail up to 60 to 90 cm (24–36 in.) and are available in pink, red, deep purple and yellow. They are sturdy plants with excellent garden performance. Supertunia ‘Raspberry Blast’ is vigorous with dark and light rose flowers. It’s ideal for hanging baskets. Tidal Wave series includes a range of colours of single flowers on very floriferous, dense and mounding plants of 20 to 25 cm (8–10 in.) with a 90 cm (36 in.) spread. They make excellent weather-resistant ground covers. Ultra series has good basal branching with large (10 cm/ 4 in.), single blooms in many colours. The weather-tolerant plants are 25 to 30 cm (10–12 in.) high.

‘White Russian’ (P. x hybrida), part of the Supertunia series, can trail up to 90 cm (36 in.) and has excellent garden performance.

Wave series has a trailing habit and is extremely floriferous, with 8 cm (3 in.), single flowers of various colours. No pinching is required. Plants are 10 to 15 cm (4–6 in.) tall. Calibrachoa x Petunia hybrids – whether they’re called Calibrachoa, petchoa, calitunia, supercals or superbells – are an outstanding new development in plant breeding. A cross of two genera, Calibrachoa and Petunia, they combine the flowering habit of the Calibracoa and the vigour and easy care of the Petunia and they’re ideal for large containers and hanging baskets. Plants are “self-cleaning” in that they do not have the sticky foliage of petunias so that spent flowers simply fall rather than sticking to the leaves. Flower colours are intense and plants have disease- and weather-resistance. With a mounding and trailing habit, they vary from 25 to 45 cm (10–18 in.) in height with a spread of 60 to 80 cm (24–30 in.). Among the cultivars are: ‘Calitunia Purple’ and ‘Calitunia Pink’ have large flowers and vigorous trailing growth on plants 20 cm (8 in.) high. SuperCal Pechoa series includes blue, cherry, pink ice, neon rose, purple, terracotta and vanilla blush on plants 25 cm (10 in.) high.

Like ‘White Russian’ (P. x hybrida), ‘Citrus’ is a cultivar of the new Supertunia series of very vigorous and sturdy plants.

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Superbells series has abundant, small, petunia-like flowers in a range of colours that bloom all season on cascading growth. They are 15 to 25 cm (6–10 in.) high, trailing over 90 cm (36 in.). CARE: Grow in full sun to partial shade. They prefer fertile, well-

drained soil but will survive a wide range of conditions. Some of the older cultivars require pinching to make the plants bushier. Deadheading may also be needed for a neater appearance and more continuous bloom, although many of the newer cultivars do not need this. Read the small print in the catalogues or on the plant labels. Petunias are frost-tender and difficult to grow from seed unless it is pelleted. The non-pelleted seed is like dust – one sneeze and you’ve lost it all! Many of the cultivars bred for containers are grown vegetatively from cuttings rather than from seed. USE: Petunias are used as edging, in hanging baskets and Calibrachoa x Petunia hybrids are an outstanding development in crossing two genera.

other containers, in borders and massed in annual beds. They are a nectar plant for hummingbirds.

California bluebells (Phacelia campanularia)

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Here is a dainty plant, somewhat understated, certainly lacking gaudiness, but with attractive flowers and foliage and a long flowering period. It should be more widely used. Phacelia is from the Greek word phakelos, meaning cluster and describes the flower arrangement. The species name, campanularia, refers to its similarity to bellflowers. Native to the deserts of the southwestern United States (including California) and Mexico, these dainty plants are 15 to 30 cm (6–12 in.) high, bushy, with small, roundish to oval, grey-green leaves that may cause an allergic skin reaction. The cup-shaped blue flowers, 2.5 cm (1 in.) in diameter, are held on reddish stems and have very distinctive, protruding white anthers and a white throat. Phacelia tanacetifolia, used agriculturally to attract pollinators to seed crops, has pale mauve-blue flowers above finely divided, lacy foliage. It is 23 cm (9 in.) in height and will grow in sun or partial shade. It is both charming and a bee magnet. CARE: Phacelia performs well in full sun in a wide range of The cup-shaped blue flowers of California bluebells (Phacelia campanularia) are held on reddish stems and have very distinctive protruding white anthers and a white throat.

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soils, excelling during hot days and cool nights. It transplants poorly, so seed should be sown directly or in biodegradable peat pots. It will reseed. USE: Use massed, as a ground cover, in mixed borders and in

rock gardens. It is attractive to bees.

Moss rose (Portulaca grandiflora)

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Don’t confuse this gem with the annual weed also known as portulaca or purslane. They are both sun-loving and succulent and are members of the same genus, but the similarities end there. While purslane (Portulaca oleracea) is a pernicious and prolific weed, moss rose (Portulaca grandiflora) is a delightful, easy-to-care-for bedding plant. The genus Portulaca was named by Linnaeus, who observed that the lid of the seed capsule opened like a gate. Portula is Latin for little gate, while the specific epithet, grandiflora, means largeflowered. It is native to Brazil, Uruguay and Argentina. Portulaca is a dwarf, trailing, mat-forming fleshy plant of only 15 cm (6 in.) in height, with a spread of 60 cm (24 in.). It produces masses of 5 cm (2 in.) satiny, single or double flowers, in white, cream, yellow, orange, red, pink or purple. The flowers close at night and on cloudy days. It has succulent, almost prostrate stems and fleshy, needle-like, blue green leaves, which often have a reddish tinge. Calypso series are taller (20–38 cm/8–15 in.), with a spread of only 25 to 30 cm (10–12 in.) and bright, double flowers.

Moss rose (Portulaca grandiflora) is an old fashioned, exceptionally drought tolerant annual that is ideal for rock gardens and containers.

Margarita Pastel mix has mounding plants of 10 cm (4 in.) with semi-double flowers in twelve colours. Sundial series (10–15 cm /4–6 in.) is early, vigorous, mounding, spreading and floriferous. The flowers, in more than twelve colours, stay open longer and under low light conditions. Tequila series tolerates cool, wet weather better than most cultivars. It has double and semi-double flowers in twelve colours and begins flowering early. Plants are 10 to 20 cm (4–8 in.) in height and spread to 35 cm (14 in.). Tutti Fruti mix (15 cm/6 in.) has double flowers in apricotsalmon tones with white. Yubi series (P. umbraticola hybrid) produces large, vibrant, single and double flowers all summer, with no deadheading required. These exceptionally drought-tolerant plants are 12 cm (5 in.) in height and are trailing. Colours include apricot, pink and salmon. CARE: Plant in full sun on well-drained soil. They are wind-,

heat- and drought-tolerant and do well on poor soils, thriving in the hottest and driest situations. It’s easiest to sow seed directly where it is to be grown. USE: A good solution for problem areas; use it as a ground cover, on dry banks, in rock gardens, containers and as edging.

Portulaca umbraticola (the species is seen above) has given rise to the exceptionally drought tolerant Yorbi series hybrids which have large flowers and do not require deadheading.

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Russian statice (Psylliostachys suworowii, syn. Limonium suworowii)

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As a student, I appreciated Russian statice both for its distinctive flowers and the sheer challenge of remembering and pronouncing the species name. Although it has been placed within a different genus (another mouthful) in the interim, suworowii remains! Plants are closely related to Limonium. The genus name, Psylliostachys, is from the Greek words psyllion, meaning a type of plantain and stachys, a flower spike. The species was named in 1886 after Ivan Peterowitch Suworow, medical inspector in Turkestan (to which it is native, along with Iran, Afghanistan and other parts of central Asia). A perennial in its native habitat, it flowers during its first season. The pencil-like spikes of tiny lavender, blue, pink or white flowers, each surrounded by a papery calyx, are on thin stems of 45 to 75 cm (18–30 in.). They are exceptionally long lasting. The narrow, glossy, spoon-shaped leaves have wavy edges and are formed in basal rosettes. The pencil-like spikes of Russian statice (Psylliostachys suworowii) are covered in tiny flowers of lavender, blue, pink or white.

CARE: Plant in well-drained, sandy loam in full sun. It soon

develops a taproot, which makes transplanting difficult, so sow seed directly or use biodegradable peat pots. USE: Use in mixed borders and as a fresh or dried cut flower. Russian statice is a nectar source for butterflies.

Black-eyed susan, gloriosa daisy (Rudbeckia hirta)

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From late summer through fall, no trip across the prairies is complete without the accompaniment of black-eyed susans by the roadside. Native to central North America, they are short-lived perennials or biennials that bloom their first year from seed and are here treated as an annual. The genus name honours Olaf Rudbeck (1660–1740), Swedish professor of botany, teacher of Linnaeus and founder of the Uppsala Botanic Garden. The species name, hirta, is Latin for hairy, referring to the fine hairs on the leaves and stems. Masses of large (up to 10 cm/4 in. wide), bright yellow, orange or bronze-red daisies appear from July through September. The distinctive dark brown centres are composed of disk florets. Plants are generally 60 to 90 cm (24–36 in.) in height. The leaves are large, narrow, lance-shaped and toothed. Some plants may overwinter, while others self-seed. Black-eyed susans (Rudbeckia hirta) have come a long way from gravelly roadsides to our gardens through modern breeding of the last few years.

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Autumn Colours mix has large single flowers in red, gold and bronze and is 50 cm (20 in.) in height. Becky series has large, single blooms on compact, extra dwarf plants of 20 to 25 cm (8–10 in.).

‘Cappuccino’ bears amber and ochre petals with a dark brown centre on compact plants of 45 to 50 cm (18–20 in.). It is very floriferous. Cherokee Sunset series (60–90 cm/24–36 in.) has semi-double to fully double flowers in orange, yellow, bronze and brown. ‘Red Cherry Brandy’ has red petals with a dark centre on robust, weather-resistant plants of 60 cm (24 in.). ‘Indian Summer’ is 1 m (3 ft) in height with 15 cm (6 in.), single to semi-double yellow flowers. It’s floriferous, sturdy and wind tolerant. Moroccan Sunset series is 60 cm (24 in.) in height with a 40 cm spread. It has double and semi-double flowers in chestnut, tawny brown and marmalade, with excellent garden performance. ‘Prairie Sun’ has single, bicolour, golden-yellow flowers, up to 12 cm (5 in.) across, with primrose yellow tips and a pale green centre, on plants 60 to 90 cm (24–36 in.) tall. ‘Tiger Eye Gold’ has single, golden flowers on uniform, wellbranched, compact plants of 40 to 60 cm (16–24 in.) with

‘Tiger Eye Gold’ (R. hirta) is a new gloriosa daisy with single, golden flowers on uniform, well-branched, compact plants. They are resistant to mildew.

mildew resistance. Toto mix (25 cm/10 in.) has semi-double flowers in a rich gold surrounding a deep chocolate cone. It is early, long flowering and weather resistant. CARE: Plant in sun or partial shade on well-drained soil. USE: It is wonderful when massed and good in containers, beds, borders, cottage gardens, for cutting and in “hot” gardens with yellow, orange and red flowers and foliage.

Salvia, sage (Salvia spp.)

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There are many drought-tolerant annual or tender perennial salvias, each adding a different dimension to our beds and borders. Salvia is a Latin word meaning to heal and alludes to the plant’s reputed medicinal properties. They are members of the mint family, with typical square stems and opposite leaves. The two-lipped flowers are arranged in whorls around the stem. Silver sage (Salvia argentea) has outstanding foliage. Formed in a rosette, it is thick, woolly, silver and gently lobed, ranging from 20 to 60 cm (8–24 in.) in height. The flowers are pinkishwhite. It is native to southern Europe. ‘Artemis’ is tall (90 cm/36 in.) with pinkish-white flowers.

The thick woolly foliage of ‘Hobbit’s Foot’ silver sage (Salvia argentea) is gently lobed and luxuriously lush.

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‘Hobbit’s Foot’ has a height and spread of 20 by 35 cm (8 x 14 in.), with gorgeous, lush, wide grey-green foliage. CARE: Place in full sun, in soil with excellent drainage. USE: Use in rock gardens, mixed borders and containers. Mealycup sage (S. farinacea) is a perennial in its native habitat of Texas into New Mexico, but treated as an annual on the prairies. Farinacea means meal, reflecting the fact that each flower is supported by a floury-looking, cup-like calyx, hence the species and common names. The small (2 cm/ 1 in.), violet-blue to lavender to white flowers are produced on long spikes and the upright plants reach up to 60 cm (24 in.) in height. The shiny foliage is grey blue. ‘Evolution’ has 15 cm (6 in.) spikes of deep, dark purple on well-branched plants of 40 to 60 cm (16–24 in.). ‘Strata’ (25 to 30 cm/10–12 in.) has silver spikes with clear blue florets and a white calyx. ‘Evolution’ mealycup sage (S. farinacea) has spikes of deep, dark purple flowers on well-branched plants.

‘Victoria’ (40 to 60 cm/16–24 in.) has spikes of violet blue or white. CARE: Plant in fertile, well-drained soil in full sun to light shade.

Do not overwater. It may self-sow once established. USE: Use in beds, borders, cottage gardens, massed, in containers

and in fresh and dried arrangements. Common sage (S. officinalis), a perennial native to the Mediterranean area, has a long history as a medicinal and culinary herb. Treated as an annual on the prairies, it is also valuable as an ornamental. Although variable in size and leaf colour, most have bluish flowers and attractive foliage. ‘Icterina’ (60 cm/24 in.) has variegated cream and green foliage. ‘Purpurascens’ (20 to 40 cm/6–16 in.) has purple-andgreen leaves. ‘Tricolor’ (60 to 80 cm/24–32 in.) is a blend of green, white and pinky-purple foliage. CARE: Plant in full sun in well-drained soil. USE: Good for edging in more formal design or the front of a Common sage (S. officinalis) has a long history of medicinal and culinary use. ‘Purpurascens’ has purple and green foliage.

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mixed border in informal situations, as well as containers. Clary sage (S. viridis, syn. S. horminum) is not planted as much as it once was, yet it always invites positive comments when

people see it for the first time. Clary sage is native to southeastern Europe and the Mediterranean and is a true annual. The species name, viridis, means green and describes the green bracts of some forms. Clary means clear-eyed, alluding to its former use in healing eye afflictions. The seeds were leached in water to use as an eyewash. Interestingly, the grey-green foliage is used in the modern pharmaceutical-cosmetic industry. Plants are 30 to 60 cm (12–24 in.) tall. The showy, petal-like bracts are in pastel shades of blue, pink, purple, cream or white, while the real flowers above the bracts are small and inconspicuous. Marble Arch mix comes in rose, deep blue and white on uniform plants of 30 to 45 cm (12–18 in.). Tricolor mix (60 cm/24 in.) is in blue, pink and white. CARE: Grow in full sun to partial shade on well-drained soil.

Sow seeds directly. It will self-seed. USE: It is good for naturalizing in dry areas, on slopes, in annual or mixed beds, containers, cottage gardens or for fresh or dried arrangements. It is excellent in a pastel border.

Creeping zinnia (Sanvitalia procumbens)

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Clary sage (S. viridis) is not seen as often as it once was which is a shame. The showy pastel bracts are in shades of blue, pink, purple, cream or white.

Related to zinnia and with a similar flower but a daintier appearance, this is a wonderful addition to hanging baskets and containers. The genus name honours Federico Sanvitali (1704– 1761), an Italian professor. Procumbens means laying flat on the ground without rooting. Native to Mexico, creeping zinnia is a low (15–20 cm/6–8 in.), mound-shaped plant with a spread of about 60 cm (24 in.). The trailing, many-branched stems produce an abundance of small, single or double, daisy-like, yellow or orange flowers with dark purple or brown centres. It is very floriferous. The oval leaves are opposite. ‘Aztec Gold’ has bright yellow flowers with a green eye on compact plants with a height and spread of 15 by 30 cm (6 x 12 in.). ‘Mandarin Orange’ has a spread of up to 15 cm/12 in. with bright orange flowers with dark centres and dark green foliage. ‘Million Suns,’ with golden-yellow flowers, blooms prolifically on compact, well-branched plants of 20 cm (8 in.). ‘Sunbini,’ vegetatively propagated, is 20 cm (8 in.) high with double the spread, has larger flowers and a more uniform habit and is very drought-tolerant.

The trailing many branched stems of creeping zinnia (Sanvitalia procumbens) are covered in daisy-like yellow or orange flowers with darker centres.

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CARE: Plant in full sun on well-drained soil. Sow directly or in

biodegradable peat pots as they do not transplant readily. Deadhead to promote continuous bloom. USE: Use in containers, hanging baskets, in annual beds, rock gardens, trailing over walls, as edging or as a ground cover in hot, dry areas.

Fairy fan flower (Scaevola aemula)

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Native to Australia and Tasmania, fan flower is a relative newcomer to North American gardens, having been introduced in the 1990s. All five petals are on one side, giving it a fan-like appearance, hence both its common and botanical names. Scaevola is Latin for left-handed (where the petals are if you happen to be looking at it from the right direction) and aemula means similar to. A perennial in its native land, it is treated as an annual on the Canadian prairies. Ranging from 15 to 60 cm (6–24 in.) in height, this plant’s Fan flower (Scaevola aemula), native to Australia, is relatively new to prairie gardens. It has trailing stems and one-sided fan-shaped flowers.

stems are creeping or prostrate, trailing up to 60 cm (24 in.). The alternate leaves are oblong, fleshy and lobed or toothed. Solitary, fan-shaped flowers with the petals pointing downward appear in leaf axils and atop the stems in lavender blue, purple or white. ‘Blue Fan’ has blue-purple flowers and is robust and floriferous, with more silver foliage on 30 to 36 cm (12-14 in.) plants. ‘Blue Wonder’ (15 cm/6 in.) is a floriferous, dark blue cultivar. ‘New Wonder’ (30 cm/12 in.) is a semi-trailing, long-flowering, heat-tolerant selection with purple flowers. ‘Whirlwind White’ and ‘Whirlwind Blue’ have a height and spread of 35 by 60 cm (14 x 24 in.), with large flowers all summer on weather-resistant plants. CARE: Plant in full sun to partial shade on well-drained soil.

They have no frost-tolerance. USE: Use for hanging baskets and containers or as a seasonal ground cover. It is great in windy locations.

Marigold (Tagetes spp.) Available in lavender blue, purple, or white, fan flower (S. aemula), is ideal for containers and hanging baskets.

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Among the most popular annuals in North America, marigolds are easy, quick, drought tolerant, pest-free, tough and dependable. In spite of all of these virtues, for decades I’ve looked down on them, regarding them as gaudy at their worst and boring at

their best. During a recent trip to Europe, however, I had a near epiphany. Some of the newer cultivars are indeed pretty amazing! This genus was named for the mythical Tages, a grandson of Jupiter, who is said to have sprung from the ploughed earth in the form of a boy. The common name, a shortened form of Mary’s gold, is associated with the Virgin Mary. Marigolds are said to represent sorrow and death. The flower heads were once used to produce a yellow dye. Marigolds vary from 15 to 60 cm (6–24 in.) in height, with single or double flowers in yellow, orange, burnt copper or creamy white. The finely cut foliage has a distinctive odour. The leaves are opposite and pinnately compound. Marigolds are very heat- and drought-tolerant, long blooming and prolific. Several species are allelopathic once mature, releasing compounds within their root zone that suppress the growth of nearby plants. This characteristic may or may not be passed on to hybrids. There are several classes of marigolds. The so-called French marigolds (T. patula) are usually shorter and bushier, with smaller flowers in yellow, orange or red. African marigolds (T. erecta), which are now being referred to as Aztec marigolds, are taller, with larger flowers. Their stems are angular and purple glands are found near their leaf margins. They are usually yellow or gold. Signet marigolds (T. tenuifolia) have extremely finely divided foliage, tiny single flowers in yellow or orange and a bushier appearance. In spite of these classifications, the marigold is originally from Mexico, where it was cultivated by the Aztec Indians. It was intro-

Marigolds (Tagetes spp.) are heat and drought tolerant, long blooming and flower prolifically. With single and double flowers in yellow, orange, burnt copper and creamy white, in heights from 15 to 60 cm (6–24 in.), there is much to chose from.

duced to Spain over four hundred years ago and was popular in monastic gardens. Modern hybrids are of varied parentage, having been developed from different species and are not as neatly classified as French or African marigolds once were. Some marigold species repel nematodes (of which there are very few in the prairies). This has given them a mostly undeserved reputation as having general insect-repellent properties, which they do not, in fact, possess. Antiqua series has early double flowers in gold, orange, primrose and yellow on compact, bushy plants of 25 cm (10 in.). Bonanza series has large, full, crested blooms in seven colours on early, bushy plants of 20 cm (8 in.). ‘Deep Orange,’ of the Moonsong series, is an intense orange with fully double, large flowers on 30 to 38 cm (12–15 in.) plants with excellent branching and strong stems. Disco series has early, single flowers from brilliant yellow to deep orange on dwarf plants of 20 to 25 cm (8–10 in.).

Marigold (Tagetes spp.), a shortened form of Mary’s gold, is associated with the Virgin Mary and said to represent sorrow and death.

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Durango series has early, anemone-like flowers in eight colours on strong-stemmed, well-branched plants of 20 to 25 cm (8–10 in.). Gem series has weather-resistant, lemon-yellow or yelloworange flowers on compact, 25 to 30 cm (10–12 in.) mounds of foliage. ‘Honeycomb’ (25 cm/10 in.) is a prolific, fully double, crested, bicolour orange. Inca II series, is shorter (30 to 35 cm/12–14 in.) and earlier than Inca I, with fully double flowers in yellow, orange, gold and primrose on strong stems. Taishan series includes large, double flowers in gold, orange and yellow on dwarf plants of 25 to 30 cm (10–12 in.) with good branching and strong stems that make a long-lasting display. Signet marigolds (T. tenuifolia) have finely divided, sometimes lemon-scented foliage and single flowers.

‘Vanilla’ (60 cm/24 in.) has creamy white flowers on very vigorous plants. The signet marigold (T. tenuifolia, syn. T. signata) Starfire mix has single flowers in stunning combinations of lemon, gold and mahogany on compact plants of 15 to 20 cm (6–8 in.). CARE: Seed directly in full sun on well-drained soils. Avoid

over-fertilizing, especially with nitrogen, which will produce an abundance of leafy growth at the expense of flowers. Regular deadheading removes the unattractive spent flowers. All marigolds are susceptible to aster yellows. USE: Dwarf cultivars are used as edging plants, in annual beds and in containers, while taller types are placed towards the middle of the border. All are useful as cut flowers. The petals are edible and are sometimes used as a saffron substitute by thrifty cooks. Marigolds are a nectar source for butterflies, bees and hummingbirds.

Feverfew, matricaria and dusty miller (Tanacetum spp.)

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Feverfew or matricaria (Tanacetum parthenium) is a case in Feverfew (Tanacetum parthenium), a short-lived perennial that has undergone numerous name changes, is covered in masses of small, white or yellow flowers with a button-like yellow centre.

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point regarding changing plant nomenclature. Once known as Pyrethrum parthenium, it had become Chrysanthemum parthenium by the 1990s, but is now officially Tanacetum parthenium. Add to this the fact that it is a perennial in kinder climates but treated as an annual on the prairies and it’s no wonder we’re left confused…

This old-fashioned plant is native to Europe and Asia. Used to relieve fevers in ancient times, feverfew ranges in height from 15 to 60 cm (6–24 in.) and is covered in masses of small, white or yellow, single or double flowers, each with a button-like yellow centre. The leaves are aromatic. ‘Aureum’ has white and yellow daisy-like flowers above chartreuse-yellow foliage and forms a low, bushy mound of 30 to 45 cm (12–18 in.). ‘Golden Ball’ (30–45 cm/12–18 in.) has double, pale yellow, pompom flowers. ‘Golden Moss’ (‘Aureum Nanum’) has double, bicolour yellow-and-white flowers above lime-green to chartreuse foliage on compact plants of 15 to 30 cm (6–12 in.), making it a good edger. ‘White Stars’ (15 cm/6 in.) has flowers with white petals and a yellow disk with green foliage. ‘Silver Feather’ dusty miller, a selection of T. ptarmiciflorum (syn. Chrysanthemum ptarmiciflorum, Pyrethrum ptarmiciflorum), is a lovely dusty miller (regardless of the botanical name!) with finely cut, delicate, silver grey foliage verging on powdery white. A perennial treated as an annual, it is 30 to

‘Silver Feather’ dusty miller, a selection of Tanacetum ptarmiciflorum, has finely cut, delicate silver grey foliage that is almost white.

60 cm (12–24 in.) high. CARE: Tanacetum tolerate poor soil, in full sun or partial shade.

Pinch in spring for bushier plants. It may self-seed. USE: While feverfew is good for naturalizing in a wildflower

garden or back lane, it is also used as edging, in annual or mixed borders, cottage gardens, pots or containers and as a cut flower. ‘Silver Feather’ dusty miller is ideal for edging and more formal designs.

Cleome, spider flower (Tarenaya hassleriana, syn. Cleome hassleriana, syn. )

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Cleome was among the first annuals I ever noticed – in a garden in Tanzania in East Africa a half-century ago. It had been directly seeded and was so easy and so effective, standing out because of its unusual flower form and height. More recently, I came across them in Claude Monet’s garden in Giverny, France in full flower in early October. The magic was still there. Native from southeastern Brazil to Argentina, cleome is widely naturalized in other parts of the world. I recall seeing masses of it near the Krakow airport. Cleome is an early Greek

Cleome or spider flower (Tarenaya hassleriana) has long protruding stamens that resemble the legs of a spider. Up to 2 m (6 ft), the fragrant flowers are in shades of white, yellow, pink, rose, lavender or purple.

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name for this plant and is thought to be from the Greek word kleos, meaning glory, alluding to the beauty of the flowers. The species is named after Emile Hassler (1861–1937), a Swiss botanist who collected plants in Paraguay. The common name is derived from the long, protruding stamens, which resemble the legs of a spider. The botanical name has recently changed. This stately (up to 2 m/6 ft), old-fashioned annual has a soft, airy appearance. The fragrant flowers are in shades of white, yellow, pink, rose, lavender or purple, blooming from late summer into fall and followed by decorative seedpods. The palmately compound, lupine-like leaves are attractive but sticky and strongly (some would say unpleasantly) scented. There are sharp, back-curving spines at the base of the leaf stalks. ‘Helen Campbell’ is an enduring older variety of 1 m (3 ft) in glistening white. Queen series has 12 to 18 cm (5–7 in.) flower clusters in rose, violet, cherry and white on 1 to 1.2 m (3–4 ft) plants. ‘Purple Queen’ has pink to purple flowers. The Sparkler Blush series of Cleome (T. hassleriana) are semi-dwarf, compact, dense, wind-resistant plants with flowers in blush, lavender, rose, pink and white.

‘Senorita Rosita’ is a pink hybrid that represents a great breakthrough in breeding. Plants are 60 to 120 cm (24–48 in.) with sterile flowers (no unwanted seedlings and no need for dead-heading!). The foliage is thornless, non-sticky and odorless. The flower clusters are small but cover the entire plant, not just the top. Sparkler series are semi-dwarf (60–90 cm/24–36 in.), compact, dense, wind-resistant, disease-resistant and freeflowering plants in shades of blush, lavender, rose, white and pink. Spirit series has pink, purple, lavender and white flowers, with thorns on the leaf stalks, on uniform, vegetatively propagated plants 60 to 90 cm (24–36 in.) high. Rocky mountain beeweed (C. serrulata) ‘Solo’ is thornless, with white to light pink flowers on 40 cm (16 in.) plants. CARE: Cleome prefers well-drained soil in full sun to partial

shade. Deadheading prolongs bloom.

Rocky Mountain beeweed (C. serrulata) is thornless with white to light pink flowers.

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USE: Mass towards the rear of a mixed border or the centre of an island bed or use as a summer hedge, as an accent plant, to screen unsightly objects, in large containers and as cut flowers. It is outstanding in a pastel border. Cleome is a nectar source for bees and hummingbirds and the seed is eaten by finches and juncos.

Dahlberg daisy, golden fleece

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(Thymophylla tenuiloba, syn. Dyssodia tenuiloba) Here is a plant that should be more widely used for both bedding and hanging baskets, but may be difficult to locate. Although its name has “officially” been changed, Dahlberg daisy more often than not remains listed as Dyssodia. Like the older botanical name, Thymophylla could describe the smell of the foliage (from the Greek words thymos, meaning excrescence). Or it could originate from thymos, the Greek word for thyme, again referring to the foliage and phyllon, leaf. Dyssodia comes from a Greek phrase meaning evil-smelling and also refers to the attractive but odoriferous foliage. Scent-producing glands are found in the papery bracts at the base of the flowers. The species name, tenuiloba, means narrow lobed, also a description of the finely divided foliage. The common name honours two brothers, Nils and Carl Dahlberg, who sent plant specimens to Linnaeus in the 1700s. Native to Texas and Mexico, the Dahlberg daisy is a spreading, bushy plant of 20 to 30 cm (8–12 in.), with pungent, fern-like, opposite leaves and such a profusion of small, yellow, single daisies that the foliage is almost completely hidden. Generally, only the species is available. CARE: It thrives in light, well-drained soil, in full sun and heat

Dahlberg daisy (Thymophylla tenuiloba) is a spreading bushy plant with pungent, fern-like foliage and a profusion of small, yellow single daisies, useful for borders, containers and hanging baskets.

where nights are cooler. It should be sown early, as flowering takes four months from seed. It may self-seed. USE: Use for edging, annual or mixed borders, rock gardens, containers (especially hanging baskets) or as a cut flower.

Mexican sunflower (Tithonia rotundifolia)

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Think large! These plants are generally 2 m (6 ft) but can be up to 3 m (10 ft) in height and the coarse leaves are 30 cm (12 in.) long. Underused, it may be in danger of disappearing from garden centres. The genus honours Tithonus of Greek mythology. Granted immortality but not eternal youth, he eventually shriveled to the size of a grasshopper. How this relates to a large plant native to Mexico and South America is unclear. Almost shrub-like in appearance, rotundifolia describes the large, round, velvety foliage. The 7.5 cm (3 in.) flowers resemble single dahlias with yellow centres and come into their own in late summer. The stems are visibly swollen just under the flowers. ‘Fiesta del Sol’ (75 cm/30 in.) is a dwarf selection with intense bright orange, single flowers.

Up to 2 m (6 ft) in height with large round velvety foliage, Mexican sunflowers (Tithonia rotundifolia) resemble large single dahlias with yellow centres and come into their own in late summer.

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CARE: Mexican sunflower is adapted to heat, sun and poor

soil. It may need staking. USE: Place them toward the rear of the border, as accents,

annual screens or use as cut flowers. They are very attractive to butterflies.

Dill-leaf ursinia, jewel-of-the-veldt (Ursinia anethoides)

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Ursinia is another South African daisy, but one seldom seen in our gardens. Finding seed may take some effort. This genus was named to honour Johannes Ursinus, a seventeenth-century German botanist. Anethoides means dill-like and describes the strongly scented and dissected leaves. Like so many other South African annuals, it resembles Gazania or Osteospermum. The bright orange-yellow, single, daisy-like flowers have a dark purUrsinia or jewel-of-the-veldt (Ursinia anethoides) is a rare annual in prairie gardens but would complement a “hot” border. Bright orange-yellow daisy-like flowers are held on thin wiry stems.

ple ring surrounding the centre and are held on thin, wiry stems, 30 to 45 cm (12–18 in.) above the finely cut, dill-like, aromatic foliage. They close at night and on cloudy days. ‘Solar Fire’ has orange flowers with burgundy rings on 38 cm/ 15 in. plants with deeply cut ferny foliage. CARE: Plant in light, well-drained soil in full sun. Deadhead for

prolonged bloom. USE: Use in annual or mixed borders and in containers. They’re good for a “hot” border.

Cape daisy, monarch-of-the-veldt (Venidium fastuosum)

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Venidium is Latin for veined and describes the ribbed seed pod. Both the species name, fastuosum and the common name, monarch, mean proud, perhaps a reference to the plant’s prominence on the South Africa veldt, to which it is native and where it is a perennial (although it is treated as an annual on the prairies). Almost sunflower-like in appearance, the large (10–13 cm/ 4–5 in.), daisy-like flowers of the species are brilliant orange, with a dark purple-black centre. Ivory, lemon, cream, pale yellow and white selections are also available. They close at night and on dull days. The amazing silver foliage is deeply cut and has a fuzzy, cobweb-like texture that is more predominant in young Another native of South Africa and almost sunflowerlike in appearance, cape daisies (Venidium fastuosum) are about 60 cm (24 in.) in height with white to orange flowers with dark centres.

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plants. Plants are about 60 cm (24 in.) in height. ‘Jaffa Ice’ is orange and white with 10 cm (4 in.) flowers. ‘Zulu Prince’ has large (10 cm/4 in.), pure white flowers with black centres on long, 75 cm (30 in.) stems. ‘Orange Prince’ is similar but orange.

CARE: Grow in well-drained, light soil in full sun. It does better

in heat. USE: Use in annual or mixed borders and as a cut flower.

Verbascum, dark mullein (Verbascum nigrum)

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I’ve had a love-hate relationship with verbascum for decades. I love the stately spikes of flowers and the soft foliage, but I can’t tolerate its prodigious self-seeding! If I were a more meticulous gardener and deadheaded on schedule, it would be less problematic, but alas, I am less than meticulous... The common name, mullein, is from the Latin mollis and means soft, a description of the leaves. Mulleins are native to Europe, but many species are widely naturalized in eastern North America. Biennial in nature, verbascum perpetuates itself through reseeding. Plants are 1 m (3 ft) in height, with tall spikes of yellow flowers from midsummer into fall. The large basal leaves are heart-shaped and arise from thick, fleshy roots. CARE: Plant in full sun. Deadhead to prevent seeding and to

encourage rebloom. This plant has no conception of planned parenthood.

Verbascum (Verbascum nigrum) produces stately spikes of yellow flowers from midsummer to fall.

USE: If you can’t or won’t deadhead, limit its use to cottage gardens, for naturalizing and cut flowers.

Johnny-jump-up (Viola tricolor)

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Years ago, I was gently advised that if I planted a johnny-jumpup in my garden, I would always have them. That has proved all too true. Do I mind? Not really. They provide a nice surprise each year. Native to Europe, johnny-jump-up is biennial in nature. It has escaped from cultivation and become naturalized in much of North America. The species name, tricolor, means of three colours and describes the small blue, yellow and white blossoms. Only 10 to 15 cm (4–6 in.) in height, it blooms through most of the summer. It has been used in the breeding of many of the modern pansies. CARE: Johnny-jump-up will grow in sun or shade in any sort of soil. Late in the season they may get powdery mildew. USE: It is useful for naturalizing or the wild garden. It self-seeds

too readily for perennial borders or rock gardens, but may easily end up in one.

Useful for naturalizing or in a wild garden, Johnny-jump-up (Viola tricolor) is a delightful biennial.

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Immortelle (Xeranthemum annuum)

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Light, airy and delicate, this is an excellent addition to a pastel border. It has an extended period of bloom, from midsummer to fall. The genus name comes from the Greek words xeros, dry and anthos, flower and refers to its use as a dried flower or everlasting. The common name is a similar allusion. Native from the Mediterranean to Iran, it has been in cultivation for centuries. The small, papery daisies are single or double, in white, pink, purple, lilac or rose, with petal-like bracts. The hairy leaves are silver grey. The plants are 60 to 90 cm (24–36 in.) in height, with erect, branching stems. Paper Roses series has four colours of double, crested flowers on strong stems, 65 cm (26 in.) in height. CARE: It grows best in sandy soil in full sun. Sow seeds directly

or into biodegradable peat pots. Immortelle (Xeranthemum annuum) has small papery, single or double daisies in white, pink, purple, lilac or rose that are good in a border or for fresh or dried arrangements.

USE: Grow immortelle as mass plantings, in borders and for fresh or dried arrangements.

Strawflower (Xerochrysum bracteatum, syn. Helichrysum bracteatum)

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As a horticultural student, I mastered the botanical name for this plant by treating it as a ridiculous swear word: heal-e-chrissum brac-a-tum!! It worked. With all of the recent changes in botanical nomenclature, one is sorely tempted to try this strategy a second time – but out of pure frustration! The Greek words helios (sun) and chryso (golden) of the older botanical name refer to the flower. Xeros, of course, means dry, the texture of the petals. The species name, bracteatum, describes the stiff bracts below the flower. Native to Australia, where they are perennial, strawflowers are classic, old-fashioned everlastings – long-stemmed (30–60 cm/ 12–24 in.), daisy-like, up to 8 cm (3 in.) in diameter, in shimmering shades of white, yellow, orange, salmon, red, pink or purple. The papery, petal-like bracts are dry and sharp to the touch. They bloom from mid to late summer above narrow, pointed, silver leaves. Bikini mix is a dwarf blend of 30 cm (12 in.) with double Another old fashioned annual grown mainly for dried flower arrangements, strawflowers (Xerochrysum bracteatum) are also well placed in a border.

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flowers in eight non-fading colours. Chico series is 30 to 45 cm (12–15 in.) in height, with 5 cm (2 in.), double flowers in orange, pink, red, white and yellow that come into bloom earlier than most.

CARE: Plant in full sun on well-drained soil. Deadhead for

a neater appearance and more continuous bloom. Avoid over-watering. USE: Long a favourite in fresh and dried arrangements, strawflowers are also useful in borders. If used for drying, cut them before they are fully open.

Zinnia (Zinnia spp.)

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Originally from Mexico, where it was cultivated by the Aztecs, Zinnia elegans is one of our most popular annuals. There are many cultivars. In the presence of these omnipresent annuals, one is tempted to cry out, “Try something different!” Selections from the species Z. angustifolia (narrow-leaf zinnia) and Z. haageana (Haage’s zinnia) are beginning to provide that difference. The former is useful in rock gardens; it is more disease-resistant and less in need of deadheading. Haage’s zinnia, also disease-resistant, generally has smaller, bicolour flowers, but it will need deadheading. Linnaeus named this genus for German botanist Johann Gottfried Zinn (1727–1759). Elegans means elegant. The flowers, held on stiffly erect stems, are single or double, in form

Narrow-leafed zinnia (Zinnia angustifolia) is a dainty plant with narrow leaves. ‘Crystal White’ has small single flowers that cover the bushy, 20 cm (8 in.) plants.

ranging from cactus-flowered to pompom, in every colour but blue. Cultivars generally vary in height from 15 to 100 cm (6–40 in.). The leaves are oval, somewhat hairy and clasp the stem. Benary’s Giant series has extra large (10-13 cm/4-5 in.) fully double flowers in many colours, on sturdy, 100 to 125 cm (40-50 in.) stems. Magellan series, in six colours, has fully double flowers that do not require deadheading, on vigorous, uniform plants of 30 to 35 cm (12–14 in.). ‘Uproar Rose’ (70 to 90 cm/28–36 in.) has large (10 cm/ 4 in.), double, magenta-rose flowers. Zahara series (30 to 35 cm/12–14 in.) has large, single blooms in several colours. ‘Zowie Yellow Flame’ (60 cm/24 in.) has large (7–10 cm/ 3–4 in.) blooms with a magenta-orange centre shading to yellow tips. Narrow-leafed zinnia (Zinnia angustifolia), native to the southwestern United States and Mexico, is a dainty plant with narrower leaves.

‘Coral’ from the Megellan series of zinnia (Z. elegans) has fully double flowers on vigorous uniform plants and does not require deadheading.

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Crystal mix (20 cm/8 in.) has small, single flowers of orange, yellow or white that cover the bushy plants. Profusion series (30–45 cm/12–18 in.) has a “profusion” of single flowers in several colours that do not require deadheading. Haage’s zinnia (Zinnea haageana), native to Mexico and also called the Mexican zinnia, has narrower leaves with single or double flowers. ‘Persian Carpet’ has 5 cm/2 in., double bicolour blooms in gold, maroon, purple, chocolate, pink and cream on plants 30 to 45 cm (12–15 in.) high. ‘Star White’ with startling white petals and golden yellow centres is 45 to 60 cm (18–24 in.) high. CARE: Plant in full sun on well-drained soil. It is easy to sow ‘Starlight Rose’ from the Zahara series of zinnia (Z. elegans) has large single blooms atop 30 to 35 cm (12–14 in.) stems.

seeds directly. Deadhead for continuous bloom. Mildew is sometimes a problem. Smaller cultivars perform better during cooler summers than the taller ones, which may not reach their potential without sufficient heat. USE: Use in beds, containers, as edging and as cut flowers. They are a source of nectar for butterflies and hummingbirds.

“Vines form the vertical dimension of our gardens. They tie a house to its surroundings, lowering it into the landscape and making it an integral part of its setting.”

Haage’s zinnia (Z. haageana) has narrow leaves with single or double flowers. New cultivars in various colours have been introduced.

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CHAPTER 10

Vines Vines form the vertical dimension of our gardens. They tie a house to its surroundings, lowering it into the landscape and making it an integral part of its setting. Vines also provide us with a garden ceiling on an arbor, trellis or pergola. They help to break up a large expanse of wall or fence. They can be used to accent positive features, as a focal point, as well as to provide privacy for a deck or porch. On the other hand, they can also screen or hide that which you don’t wish to be a part of your landscape. And all the while, they lend colour and texture in the form of flowers and sometimes even scent or fruit. Select your vines carefully so they are in scale with the area of your garden in which they are placed.

Dutchman’s pipe (Aristolochia durior, syn. A. macrophylla) This is an old-fashioned perennial vine native to the east coast of North America as far inland as Ontario. Although classified as zone 4, it has survived in sheltered locations immediately next to the foundations of at least two homes “beyond the zone,” one in Swift Current and one in Saskatoon. At one time, it may have been used medicinally during childbirth – the genus name is from the Greek words aristos (best) and lochia (childbirth) and one of its earlier common names was birthwort. A woody climber reaching about 10 m (30 ft) in height, the alternate, glossy, dark green leaves are large (30 cm/12 in.) and triangular to heart-shaped. The unusual purple-yellow flowers, usually hidden by the foliage, resemble a small meerschaum pipe,

A perennial that is generally treated as an annual, Dutchman’s pipe (Aristolochia durior) may overwinter in a protected spot immediately next to a house foundation.

thus the common name. They are kidney-shaped with cream veining on a velvety maroon background. The fragrance of the flowers attracts flies that pollinate them. It is vigorous and fast-growing.

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CARE: Plant in sun or shade. It is adaptable to most soils. USE: Dutchman’s pipe produces dense shade and is excellent for covering porches or pergolas, screening unsightly objects or covering buildings.

American bittersweet (Celastrus scandens) Native to North America, including the eastern portion of the prairie region, bittersweet is seldom seen in our gardens, which is unfortunate. The genus name is derived from the Greek kelastros, meaning late season, a reference to the prolonged retention of the fruit. Scandens means climbing. The flowers are small and white, but it is the fruit that’s attractive. The orange fruit split to reveal scarlet seeds, giving it unusual fall and winter landscape value. The oval to oblong leaves are pointed and turn bright yellow in the fall. Vigorous vines, they climb with twining stems to 7 m (24 ft) or higher. They will need a support on which to climb. A plant may produce male, female or perfect flowers. To ensure fruit, place several plants of the species in close proximAmerican bittersweet (Celastrus scandens) has orange fruit that split to show scarlet seeds. Ensure you have a male and female plant in close proximity or a selffertile cultivar.

ity, select a cultivar with perfect flowers or plant both a male and a female cultivar. ‘Autumn Revolution’ is self-fertile, so no pollinator is needed for the production of orange berries. The fruit is considerably larger than that of the species. ‘Diana’ is a female selection. ‘Hercules’ is a male selection. CARE: Plant in full sun in a wide range of well-drained soils. USE: Bittersweet is used to cover fences and pergolas, as a

ground cover and to hold slopes. The fruiting stems are attractive in winter bouquets and in dried arrangements and the fruit is eaten by birds.

Clematis (Clematis spp.) Clematis is the Greek word for a climbing plant. The leaf stalks of these perennial vines act as tendrils, wrapping around whatever support is available and the vines may reach 3.5 m (12 ft) or higher. Not all clematis are created equal. If you’re after hardy, drought-tolerant clematis, just remember a few botanical ‘Joe Zary’ is a double purple clematis that blooms all summer.

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names and read the small print on the plant labels. Native to the northern temperate regions of the world, the small-flowered species of clematis and their hybrids are hardier and more

drought tolerant than the large-flowered types. Clematis alpina, from the mountains of southern Europe and C. macropetala, from China, have been used in the development of some excellent hybrids that are both hardy and drought tolerant. Both these species and their cultivars flower in spring on old wood. The cultivars range from 2 to 3.5 m (6–12 ft) with flowers in blue, purple, pink, red or white. Among them are the following: ‘Bluebird’ has flat, outward-facing, deep blue flowers, 6 cm (2.5 in.) in diameter, blooming for up to eight weeks on old wood. ‘Blue Boy’ (C. macropetala x C. viticella) is a prolific bloomer of 2 m (6 ft), with 6 cm (2.5 in.), outward-facing, blue flowers produced over a long period in midsummer on new wood. ‘Francis Rivis’ is a deep blue. ‘Joe Zary’ is a double purple that blooms all summer. ‘Lagoon’ (syn. ‘Blue Lagoon’) is 2.5 m (8 ft) with deep blue flowers. ‘Rosy O’Grady’ (C. macropetala x C. alpina) has large, dark pink flowers with long, pointed sepals that bloom on old wood in May and June and occasionally on new wood in August. ‘Ruby’ has nodding, rosy-red blooms with white petaloid stamens. ‘White Swan’ is a profusely blooming, double, snowwhite hybrid with 12.5 cm (5 in.), nodding flowers on both old and new wood on a 2.5 m (8 ft) vine. C. ligusticifolia (western virgin’s bower) is up to 7 m (24 ft) in height. Native to the southern prairies, it bears small white flowers, 2 cm (1 in.) in diameter, in late summer. It has pinnately compound leaves. It is dioecious, with male and female flowers on separate plants. If plants of both sexes are grown in proximity, it can set copious quantities of seed, which will develop into copious numbers of unwanted seedlings. ‘Prairie Travelers’ Joy,’ is a very drought tolerant selection, with star-like, white flowers produced over a long season and a height of 4 m (13 ft). C. tangutica (golden clematis)

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is native to northwest

China and has nodding, soft yellow, bell-shaped flowers in midsummer, followed by silvery, feather-like seed heads. It is 3 m (10 ft) or more in height and very vigorous.

Frank Skinner of Manitoba, an early prairie plant breeder, left us an enormous living legacy, including a number of clematis. ‘Rosy O’ Grady’ (top) has large, dark pink flowers while ‘White Swan’ (below) is a prolific bloomer with double snow-white flowers.

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‘Bill MacKenzie’ is a vigorous cultivar that blooms from June to September. Note: C. tangutica is classified as a noxious weed in Alberta and is illegal to grow in that province. CARE: Plant clematis in full sun or partial shade in a deep,

loamy soil to which organic matter has been added. Keep evenly moist through establishment, after which they are very drought tolerant. They will need a support on which to climb. USE: Use clematis to cover arbors or trellises, break up large

expanses of fences or walls, screen unsightly objects or provide shade. They are also useful as ground covers or to hold slopes.

Wild cucumber (Echinocystis lobata) Native to North America, including the Canadian prairies, wild cucumber is an annual vine capable of climbing up to 6 m (20 ft) in a long, warm growing season. The genus name comes from the Greek words echinos, meaning hedgehog and krystis, bladder, The seed pods of wild cucumber (Echinocystis lobata) are large, oval and spiny.

a reference to the 5 cm (2 in.), spiny, oval seed pods. The small, greenish-white flowers are inconspicuous and borne in midsummer. The light green, lobed leaves are 7.5 to 13 cm (3–5 in.) across. CARE: Wild cucumber thrives in hot weather. Plant it in a warm

location in full sun to partial shade. The tendrils will need some support to cling to. USE: Often used to cover unsightly objects, it will also do well over fences or trellises.

Silver lace vine (Fallopia baldschuanica, syn. F. aubertii, Polygonum aubertii)

This perennial is only hardy to zone 4 so it is generally treated as an annual in colder zones. In an earlier era and further south, it was much used as “porch decoration.” It was named after the French missionary Aubert, who (like many other French missionaries) was a plant collector and first introduced it from China. Silver lace vine is almost always described as one of the fastest growing vines available and has been given the moniker the “mile-a-minute plant.” Vigorous and twining, it can achieve 6 m (20 ft) in a single season. It produces masses of lightly fragrant, Silver lace vine (Fallopia baldschuanica) is fast growing and sure to provide almost instant gratification in terms of cover-up.

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white or greenish-white flowers in dense panicles in September. The green foliage emerges red in the spring. CARE: It will grow in full sun to shade. Give it a strong support on

which to twine and prune as needed if it becomes too robust.

USE: Use silver lace vine for shade, to screen for privacy or to hide unsightly objects.

Hops (Humulus lupulus)

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The genus name, Humulus, is from the same root as the word humus, meaning soil. Hops hug the soil and act as a ground cover when they have no support on which to climb. The species name, lupulus, means wolf and comes from an older name, willow wolf, referring to its habit of climbing through willows. Native to the Qu’Appelle Valley, hops are a fast-growing, vigorous climber. They are herbaceous in habit, dying down to the snow line each winter, but are capable of quickly climbing 6 m (20 ft) or more in a single season. They climb with twining shoots and will form a dense cover. The small, greenish-white flowers are produced in panicles in the leaf axils in June. The female flower matures to form a papery cone, commonly known as a hop, which imparts the characteristically bitter taste to beer. Male and female flowers are borne on separate plants. A plant of each sex is required to ensure fruit production. The cultivars below provide everything you’d wish from a vine and are also ideal for brewing beer. ‘Brewer’s Gold’ is a female selection with high yields of hops. ‘Magnum’ is a female selection with high yields of hops. Golden hops (H. lupulus ‘Aureus’) is similar to the species but with very attractive golden-yellow foliage. CARE: Hops thrive on neglect. Plant in a sunny or partially

shaded location on well-drained soil, water once or twice and then stand back. If grown in the shade, flower and fruit production are reduced. Once established, it is heat- and drought-tolerant. It will need support. USE: An excellent vine for screening or as a ground cover, hops have the added bonus of being a raw ingredient for beer – the perfect plant for the brewer turned gardener!

Morning glory (Ipomoea spp.) Here is a large genus of plants, most native to Mexico, which includes both annuals and perennials. A number of species have undergone name changes and may be listed variously in seed catalogues and on nursery benches. The perennial members of this genus are tender and “treated as annuals” but will bloom their first season from seed. The genus name is from the Greek

Golden hops (Humulus lupulus ‘Aureus’) is similar to the species but with golden foliage. Hops (below) produce cones used in beer making.

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words ips, meaning a vine tendril and homoios, similar to, and describing its method of climbing. Some of the species bloom in the morning and others at night. For round-the-clock enjoyment, plant one of each type on the same trellis. Moon vine (Ipomoea alba, syn. Calonyction aculeatum) is meant for a night garden – one with many white or fragrant flowers and a romantic ambience. Place it where you will enjoy it. The sweetly fragrant, white, funnel-shaped flowers, which bloom in the fall, open at dusk. It takes them about five minutes to open and is akin to watching a slow-motion film. Try it! The flowers are about 15 cm (6 in.) in diameter. The stamens protrude beyond the petals. The spiral buds are as attractive as the flowers. The seed pods are decorative and interesting. The green leaves are long-stalked, lush and heart-shaped. Moon vine (I. alba) is the perfect plant fort a night garden, lending scent and echoing moonlight.

A perennial in the tropics, here it is treated as an annual. Plants grow to about 3 m (10 ft). Flag of Spain or firecracker vine (I. lobata, syn. Mina lobata) has flowers that resemble those old-fashioned, garish yellowand-orange Halloween corn candies on 10 cm (4 in.) spikes. Weird! The buds of the small, tubular flowers change from red to orange and yellow as they open, later fading to white. The leaves have three pointed lobes and a fourth smaller (or mini) lobe, hence the older species name. Native to Mexico, where it is a perennial, it is treated as an annual on the prairies but should grow to about 3 m (10 ft) and bloom in September if our season is long enough. ‘Citronella’ has lemon-yellow flowers. ‘Jungle Queen’ is 3.5 m (11 ft) and crimson orange to yellow. Cardinal climber (I. x multifida) is a cross of I. coccinea and I. quamoclit. The small, scarlet flowers have a white throat and stamens that extend beyond the petals. The leaves are palm-shaped and deeply cut into several lobes. It grows to about 3 m (10 ft). Common morning glory (I. purpurea, syn. Convolvulus purpureus)

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is originally from Mexico. It reseeds where

conditions are favourable and is now found throughout the tropics and is considered a weed in some agricultural areas of the United States. It has large (10 cm/4 in.), hairy, heartshaped leaves and will climb about 3 m (10 ft). The flowers of the species are a deep purple blue, but the cultivars can be The flowers of flag of Spain or firecracker vine (I. lobata) are unique, resembling old fashioned Halloween corn candy.

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single or double, in white, blue, purple, red or pink. ‘Carnival’ (‘Carnevale di Venezia’) – pinstripes of mixed shades.

‘Hazelwood Blues’ – shades of blue. ‘Light Blue Star’ – light blue. ‘Split Personality’ – single, magenta pink-and-white flowers. ‘Star of Yelta’ – purple flowers with a pink throat. ‘Sunrise Serenade’ – double red. Cypress vine (I. x quamoclit), a true annual, is also native to Mexico. It will self-sow and is considered a weed in Australia, where it is widely naturalized. Cypress vine is covered with masses of tiny, fragrant, bright red, tubular flowers, which attract hummingbirds. The distinctive, dark green, pinnate leaves are tiny, fern-like and resemble needles. It will grow to 2 m (6 ft). Morning glory (I. tricolor)

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was used by the ancient

Aztecs both as medicine and a hallucinogen. Native to

Cypress vine (I. x quamoclit) is covered with tiny, fragrant, bright red tubular flowers.

Mexico, where it is a perennial, it was introduced to Europe in the 1600s. On the prairies, it is treated as an annual and blooms its first year from seed. Related to the sweet potato, it is fast-growing to 2.5 to 3.5 m (8–12 ft), with large, heartshaped leaves. The species name, tricolor, is a reference to the flowers, which are trumpet-like, 8 to 12 cm (3–5 in.) in diameter, single or double, in white, blue, purple, red or pink, with a white throat. Older cultivars close at midday, but most of the newer ones remain open until dusk. All plant parts are believed to be poisonous. ‘Cameo Elegance’ – variegated foliage, rose-red flowers with a white throat. ‘Candy Pink’ – pink. ‘Heavenly Blue’ – red in the bud, the flowers have intense blue shading. ‘Pearly Gates’ – white. ‘Peggy Gates’ – red-and-light purple bicolour. ‘Scarlet O’Hara’ – wine red flowers. ‘Split Second’ – resemble double pink peonies. ‘Tie Dye Blue’ – blended blue and purple flowers and variegated foliage. CARE: Morning glories will grow in full sun to partial shade

and in poorer soils. Richer soils and too much water or fertilizer result in lush growth and few flowers. The vines are surprisingly heavy and need sturdy support around which to

Morning glory (I. tricolor) may need water when seeded, but by mid-summer it’s one tough, drought-tolerant plant. It’s available in red, pink, blue, white and purple.

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twine, whether fencing, lattice or a trellis. They are available at garden centres as plants, but many of these can be seeded directly where they are to grow. For better germination, the seeds should be either gently nicked or soaked in warm water overnight prior to sowing. USE: Use to screen unsightly objects, break up expanses of fence, over a trellis or pergola, as a ground cover and in boxes and hanging baskets.

Hyacinth bean (Lablab purpureus, syn. Dolichos lablab) The first thing that strikes me about this plant is that the botanical name sounds so very unbotanical. It’s more like an Morning glories can be grown in sun or partial shade, but do better on poorer soils on a “lean and mean” diet. Hold back on the fertilizer and don’t overwater.

emphatic reply to the question, “What kind of dog is that?” Older references, especially from the American south, call this an “old-fashioned porch plant” because before the era of patios and decks, it was once used to shade almost every porch from the sun. Native to Asia and a member of the legume family, the 12 cm (5 in.) edible purple pods are a food crop in the tropics. It is a tender perennial that is treated as an annual. A twining vine with purple stems, it will grow to a height of 2 m (6 ft) or more. Clusters of fragrant, light mauve or purple, pea-like flowers are held on long, slender petioles emerging from the leaf axils. The deeply veined leaves (15 x 15 cm/6 x 6 in.) are opposite, heart-shaped and trifoliate (consisting of three leaflets). ‘Albus’ – white flowers and fruit. ‘Ruby Moon’ – bicolour pink flowers, purple pods. CARE: Plant in average to dry, well-drained soil in full sun. It will need a strong support on which to twine. USE: Use to screen porches or pergolas.

‘Dropmore Scarlet Trumpet’ honeysuckle (Lonicera x brownii ‘Dropmore Scarlet Trumpet’) ‘Dropmore Scarlet Trumpet’ is a woody vine introduced by Dr. Frank Skinner of Dropmore, Manitoba in 1950. A hybrid of Lonicera sempervirens and a L. hirsuta collected in northern Minnesota, the flowers are sterile. They begin blooming in June and continue Hyacinth bean (Lablab purpureus) was once used to shade porches through the American south. The edible pods are a tropical food crop.

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less profusely until frost. It is about 3 m (10 ft) in height, with clusters of bright orange, trumpet-shaped flowers. CARE: Plant in full sun or partial shade in a loamy soil, well

amended with organic matter. In shadier locations, flowering

will be reduced. Mulching is recommended. Keep evenly moist during establishment. Netting or trellis is needed to support the twining stems. USE: It is excellent on lattices or trellises, mailboxes or posts.

Virginia creeper (Parthenocissus quinquefolia)

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Virginia creeper is known for its brilliant scarlet fall colour, which is a knockout. The genus name is from the Greek parthenos (virgin) and kissos (ivy), which is also a rough translation of the common name. The species name, quinquefolia, means five leaves and describes the palmately compound leaves. It is an extremely vigorous woody vine, climbing to 15 m (50 ft) or more. The small, greenish-white flowers are inconspicuous. The fruit is a small blue berry that resembles a grape. It climbs by tendrils and will need a strong support. Engelman’s ivy (Parthenocissus quinquefolia var. engelmannii) differs from the species in that it is less susceptible to pow-

‘Dropmore Scarlet Trumpet’ honeysuckle (Lonicera x brownii), another Frank Skinner introduction, grows about 3 m (10 ft) and blooms for most of the summer.

dery mildew and it has holdfasts or “adhesive pads” at the end of each tendril. These allow it to climb without additional support, but it may damage painted surfaces. It may not be as hardy in colder regions of the prairies. CARE: Plant in full sun or partial shade in a variety of soils.

Powdery mildew and leaf hoppers are sometimes a problem. USE: Virginia creeper will cover large expanses of wall very

quickly and can also be used as a ground cover, especially on slopes.

Nasturtium (Tropaeolum majus) Its nomenclature is somewhat warlike. The genus name is from the Latin trapaeum, meaning a trophy. The flowers are said to resemble helmets and the leaves, shields. The common name is from the Latin nasus, nose and tortum, twist, which would describe one’s face after tasting the leaves and flowers, which contain mustard oil and have a tangy, peppery flavour. These annual vines are native to the highlands of Mexico, Peru and Chile. In cultivation for over three centuries, they are most recently being marketed for use in salads and as garnishes. The flowers are funnel-shaped, single or double, in creamywhite, yellow, orange, pink or red. Some are fragrant. The vines are 0.5 to 3.5 m (1-12 ft) in height. The leaves are round, with veins radiating from their centres.

Known for its brilliant red fall colour, Virginia creeper (Parthenocissus quinquefolia) produces small inedible blue berries and climbs by tendrils.

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‘Empress of India’ has dark foliage and crimson flowers. Jewel of Africa series has cream-and-green marbled foliage and comes in a mix of vibrant colours. ‘Strawberry Cream’ has yellow-and-red bicolour flowers. CARE: Plant in full sun in well-drained soil. Nasturtiums climb

and cling with twisting leaf stalks on string, wire, trellises or fences. Excess fertilizer or rich soil reduces flowering. Flea beetles are sometimes a problem. USE: Taller selections are used for screening and over trellises, dwarf types in beds, hanging baskets and boxes. Both are useful as ground covers.

Riverbank grape, Manitoba grape (Vitis riparia) Native to the prairies, Manitoba grape is a vigorous, woody climber reaching up to 5.5 m (18 ft). The genus name, Vitis, is the Latin word for grapes. Both the species and common names Famous in Claude Monet’s garden in Giverny, France, nasturtiums (Tropaeolum majus) are equally at home in prairie gardens.

allude to its presence on riverbanks, where it uses nearby trees as support. The small, greenish-white flowers are inconspicuous. Grown primarily for its attractive foliage, which turns yellow in the fall, it does produce small blue fruit suitable for jams and jellies. Plants are dioecious, so male and female plants must be nearby to ensure fruit production. It climbs using tendrils, which will need support. The following improved hybrids are not dioecious, so only one plant is required. These produce better with more even moisture and in a sheltered location. ‘Beta’ is from a cross of the Concord grape and a selection of V. riparia, the wild riverbank grape. It is self-fertile, ripens in September and bears dark blue-black fruit useful for jellies. ‘Valiant’ is a cross between ‘Fredonia’ and V. riparia selected by South Dakota State University. It is very hardy and produces blue grapes suitable for juice and jelly. CARE: Plant in sun or partial shade in a loamy soil to which

organic matter has been added. Mulch is beneficial. Even moisture is needed during the first few years. Once established, the species is drought resistant. Leafhoppers and powdery mildew are sometimes problems. Our native riverbank grape (Vitis riparia) is hardy, droughttolerant and vigorous and the edible fruit is used for jellies and jams.

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USE: Riverbank grape is excellent for covering large expans-

es of wall, as a “garden ceiling” for large arbors or as a ground cover.

CHAPTER 11

Bulbs There are many bulbs that are both hardy on the prairies and drought-tolerant. Some are native, others are from Europe or Asia. They flower in all colours of the rainbow, with heights ranging from 15 (6 in.) to over 150 cm, (5–6 ft) providing the possibility of bloom from early spring to late August. Almost all require good drainage – they will simply rot if placed where water sits. If in doubt, develop berms. And best of all, given the right location, they will last for a long time, requiring division every four years or so. They are generally purchased and planted in the fall and bloom the following season. While most of us are familiar with the well marketed and visually larger tulips and lilies, there are other bulbs: ornamental onions and a group that is collectively referred to as “minor bulbs.” These are the small ones: Siberian squill, grape hyacinth, glory of the snow and striped squill. They are called minor bulbs because both the bulbs and the plants that develop from them are small in size and because they make up a very minor part of the international bulb trade. But small is good. They are a standout in prairie gardens and should be planted much more frequently than they are.

Allium, ornamental onion (Allium spp.)

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Attractive, drought-tolerant, long-lived and trouble-free, alliums are among the most versatile yet underused hardy bulbs

The drumstick onion (Allium sphaerocephalon) blooms in midsummer with wine red, drumstick-shaped flowers on 60 cm (24 in.) stems.

available to prairie gardeners. Most of the alliums grown in prairie gardens are from Asia, but there are over six hundred species worldwide, some of which are adapted to our conditions. Don’t be put off because the foliage may smell of onions. Allium is from the Latin word for garlic, but they are also

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related to lilies. Some of the flowers are fragrant and all are lovely. Colours include white, pink, yellow, red, purple and blue. Heights range from 25 to 90 cm (10–36 in.). Most are summer blooming. Aflatun onion (Allium aflatunense) has lilac-purple or light violet flowers with darker veins. The flowers are drumstick in shape (some more so than others) 6 to 10 cm (2.5–4 in.) in diameter and bloom in May and June. Native to Siberia and Turkestan, it is 45 to 75 cm (17–30 in.) in height, with strapshaped leaves. ‘Purple Sensation’ has bright purple flowers, 10 cm (4 in.) in diameter, which bloom in early summer on 90 cm (36 in.) stems. ‘Mount Everest’ (A. aflatunense x A. stipitatum) is similar to ‘Globemaster’ (the A. christophii hybrid) but with white flowers on 60 cm (24 in.) stems. The aflatun onion (A. aflatunense) has light purple flowers in early summer. One of its most popular cultivars is called ‘Purple Sensation.’

‘Lucille Ball’ (‘Lucy Ball’) (A. aflatunense x A. elatum) is deep lilac and 100 cm (40 in.) in height with flower heads of 12 cm (5 in.). Blue globe or azure onion

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(A. caeruleum, formerly A.

azureum) has deep blue, globular flowers with darker central veins. These are alluded to by the former species name, which means dark blue. The flower heads are 3 to 4 cm (1–1.5 in.) in diameter, borne on 30 to 60 cm (12–24 in.) stems in June. Nodding onion (A. cernuum)

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is native to gravelly and

rocky areas of the prairies. Thirty to 60 cm (12–24 in.) in height, it has pink to white flowers in a loose, nodding head and blooms in summer. The foliage is grey green and somewhat flattened. Star of Persia (A. christophii) is less than 30 cm (12 in.) in height with large purple flowers with silver highlights in May and June. It needs a protected location. ‘Globemaster’ (A. christophii x A. macleanii) is violet and 20 cm (8 in.) in diameter. Yellow onion (A. flavum) has graceful, sweetly scented, lemon-yellow florets which form the umbel and are tier-like in effect, with the centre ones erect and the outer ones falling. It is 40 cm (16 in.) high, blooming in late summer. The foliStar of Persia (A. christophii), borderline hardy, boasts enormous silver purple flowers in early summer.

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age is grey blue. It is native to the dry hills of central Europe and Asia.

Giant onion (A. giganteum) from central Asia, Iran and Afghanistan, should be placed in a more protected location. It is gigantic as alliums go, 60 to 90 cm (24–36 in.) in height with large (10 cm/4 in.) globes of pink flowers above narrow leaves in late spring. Turkestan onion (A. karataviense) named after a mountain range in Kazakhstan, is short-stemmed and only 25 cm (10 in.) high, but has one of the larger flower heads of the hardy onions. The spherical, pale pink or purple flower heads, which are composed of star-shaped florets and bloom in early spring, are 7 to 10 cm (3–4 in.) in diameter. The two to three broad basal leaves are grey purple and held almost horizontally. ‘Ivory Queen’ is a selection with ivory-white flowers.

Golden garlic (A. moly) is a perfect candidate for the rock garden.

Golden garlic (A. moly) has star-like, buttercup yellow flowers in early spring on 30 cm (12 in.) stems above wide, grey-green basal leaves. In Europe, its native habitat, it is found in shaded areas of rock and gravel. Ostrowsky onion (A. oreophilum, formerly A. ostrowskianum, hence the common name), has carmine pink flowers on 15 to 20 cm (6–8 in.) stems in midsummer above graceful, curled leaves. Oreophilum means mountain-loving; it is native to the Caucasus Mountains and Turkey into Iran and Afghanistan. ‘Zwanenburg’ is a deeper pink. Chives (A. schoenoprasum)

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forms dense clumps, 30 to

45 cm (12–18 in.) high, with pink flowers 2 to 5 cm (1–2 in.) in diameter for much of the summer. The species name is from the Greek words schoinos (a rush) and prasum (leek) and describes the rush-like, edible leaves.

The Turkestan onion (A. karataviense) blooms in early spring.

‘Forescate’ has deeper pink flowers. ‘Profusion’ is sterile with no seedlings. Mountain garlic (A. senescens) has small, mauve-lilac flowers on 45 to 60 cm (18–24 in.) stems above glossy blue-grey leaves in late summer. It is native to Europe and Asia. A. senescens var. glauca has particularly attractive foliage, blue grey and appealingly twisting. Roundheaded leek (A. sphaerocephalon, from the Greek word for round head) is native to Europe, Asia and North Africa. It has drumstick-shaped flowers the colour of red wine. They bloom in midsummer on 60 cm (24 in.) stems above narrow, hollow leaves. The flowers are sometimes replaced by bulbils.

Edible as well as ornamental, chives (A. schoenoprasum) should be placed close to your kitchen door.

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CARE: Plant alliums in full sun on well-drained soil. Deadhead

to avoid a plethora of unwanted seedlings. USE: Use in fresh or dried arrangements, perennial or mixed

borders and rock gardens.

Glory of the snow (Chionodoxa forbesii, syn. C. luciliae) These are among the first of the minor bulbs to bloom in the spring, sometimes while there is still snow on the ground, thus their common name. The botanical name, from the Greek words chion (snow) and doxa (glory), mimics the common name and alludes to the early blooms. Most are native to Turkey. These are very small (15 cm/6 in.) plants with starry lavender-blue, white or pink flowers with six petals, yellow anthers and a white centre. The two leaves are green and grass-like. They are not loved for their individual flowers but for their collective effect en mass, which seems to appear overnight like a carpet. ‘Rosea’ is pink. Lovely and little, in a protected location glory of the snow (Chionodoxa forbesii) soon forms a carpet.

‘Pink Giant’ is 10 cm (4 in.). CARE: Plant on well-drained soil in full sun or partial shade. In

colder regions plant in a protected location. USE: Use in rock gardens and for naturalizing below trees or shrubs in partial shade.

Fritillary (Fritillaria spp.) Fritillaries are synonymous with early spring and unlike the majority of the bulbs mentioned here are well adapted to shade. They generally are in full bloom before the trees have leafed out and have disappeared into dormancy by early summer. Many species are said to smell of “dead skunk in the middle of the road,” but I have never noticed this. The genus name is from the Latin fritillus, a dicebox, a reference to the checkered flowers of some species. It is unfortunate that the hardiest fritillaries are seldom offered commercially. The two that come immediately to mind are the Siberian fritillary (F. pallidiflora) and the chocolate or Kamchatka fritillary (F. camschatcensis), although the latter is not The Siberian fritillary (Fritillaria pallidiflora) is totally hardy, drought tolerant but is seldom commercially available. Nag your supplier!

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as drought tolerant as the ones listed below. The widely marketed F. imperialis is not hardy on the prairies. Snakeshead or checkered fritillary (F. meleagris) is native to or has naturalized in much of Europe. Blooming in spring,

the boxy, square flowers are indeed checkered, with colours varying from white to mauve and dark purple. The bright green leaves are sharply pointed and 12 cm (5 in.) long. Only moderately drought tolerant, it is best planted in light shade in organic soil. Although many cultivars are available in Europe, few are sold in Canada. Michailovsky’s fritillary (F. michailovskyi) is a tiny treasure. Native to Turkey, where it grows on rocky slopes, it was originally found in 1904 by Michailovski, a plant hunter, later “lost to cultivation,” and then reintroduced in the late 1990s. It is only 15 cm (6 in.) in height, with nodding, purple-bronze bells edged in golden-yellow in spring. Siberian fritillary (F. pallidiflora, meaning pale flower)

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is one of the most hardy and easily grown fritillaries on the prairies. Native to central Asia, including Siberia and China, where it is used for medicinal purposes, it was grown in ridges similar to potato fields in wet climates. About 30 cm (12 in.) in height, it soon forms large clumps of nodding, pale yellow (sometimes with a soft tinge of green), bell-like flowers, blooming in early spring. I have grown it successfully in both a moist shaded and a dry sunny position. It

Perfect in partial shade, the snakeshead or checkered fritillaria (F. meleagris) blooms in early spring.

has naturalized through seeding in both situations. It is a terrific plant and very underused. CARE: Plant in sun or shade on any well-drained soil. USE: They soon naturalize in a mixed or perennial border,

appearing in unexpected but always welcome places.

Lily (Lilium spp.) Lilies come in all colours but blue and range in height from less than 30 cm to 2 m (1–6 ft) or more. The prairies have produced some of the foremost pioneer breeders of Asiatic and other hardy lilies in the world – Cecil Patterson, Bert Porter, Frank Skinner, Percy Wright, Fred Tarlton, Fred Fellner and Robert Simonet among them. These hybridizers have always made their selections with hardiness in mind. Most of the lilies grown in prairie gardens are Asiatic lilies, hybrids of Asiatic species. Their ancestors originated in Asia, in a climate very similar to ours. They vary in height from 25 cm to 2 m (10 in.–6 ft) and come in a generous range of colours. They bloom variously from June to late August and are classified as early, mid or late within that period. Asiatic lilies

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hybridized in Canada and the United

States are fairly disease resistant because one of the major

Only 15 cm (6 in.) ‘Little Mike’ (F. michailovskyi) is a little treasure and should be planted in groups of ten or more.

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goals of these breeders has been the production of good garden plants. Lilies hybridized in Holland are primarily for the cut flower trade and tend to be more prone to disease. The lilies listed below are tried and true and highly recommended by experienced prairie lily gardeners. They are available from both commercial growers and local lily societies. Those that are tetraploid or triplopid have more chromosomes than normal, resulting in larger, more robust plants with bigger flowers with thicker petals and sturdier stems. Orange: ‘Amaryllis’ – out-facing orange, 90 cm (36 in.), early to mid. ‘Buff Pixie’ – up-facing, buff-orange with a few tiny spots and a green nectary, 30 cm (12 in.), early. ‘Enchantment’ – up-facing orange red, with dark spots, 100 cm (40 in.), early. ‘Super Nova’ is a large, upfacing brilliant orange Asiatic lily. It is 125 cm (50 in.) high, vigorous, virus-resistant and blooms in mid-season.

‘Katinka’ – down-facing, creamy salmon orange with many maroon spots, 100 cm (40 in.), mid. ‘Parkland Orange’ – up-facing, clear orange with a few spots, 100 cm (40 in.), mid. ‘Port Alberni Tiger’ – down-facing, large orange blooms with dark spots, 2 to 2.7 m (6–9 ft), mid to late. ‘Reta’s Comet’ – out-/down-facing, vivid orange centre and throat with salmon tips and dark red spots, 150 cm (60 in.), mid to late. ‘Super Nova’ – up-facing, large, brilliant clear orange blooms, 125 cm (50 in.), vigorous and virus-resistant, mid. Yellow: ‘Butter Pixie’ – up-facing, rich golden yellow with a few spots and a green nectary, 35 to 40 cm (14–16 in.), early. ‘Connecticut King’ – up-facing, golden-yellow with a yellow green throat and no spots, 90 cm (36 in.), early. ‘Edith’ (‘Aleida’) – up-facing, soft yellow with black spots, 100 to 120 cm (40–48 in.), early. ‘Golden Age’ – up-facing, golden-yellow with a few grey-

‘Butter Pixie’ is a dwarf golden yellow Asiatic hybrid lily (Lilium) meant for the front of the border.

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purple spots, 90 cm (36 in.), late. ‘Golden Princess’ – down-facing, deep yellow with dark spots, 100 cm (40 in.), mid.

‘Gran Cru’ – up-facing, bright chrome yellow with dark spots, 120 to 150 cm (48–60 in.), early, virus resistant. ‘Helios’ – up-facing, bright chrome yellow with dark spots, 120 to 150 cm (48–60 in.), very early, virus resistant. ‘Haydee’ (‘Hilde’) – up-facing, vivid yellow with a green throat and a few spots, 100 cm (40 in.), early. ‘Ivory Pixie’ – up-facing, ivory-yellow-green with oblong red spots, 40 cm (16 in.), early to mid. ‘Lemon Queen’ – out-facing, lemon-yellow with brown spots, 140 cm (55 in.), early. ‘Moon Pixie’ – up-facing, green-yellow to vivid yellow with no spots, 40 cm (16 in.), early. ‘Northern Lights’ – out-facing, straw yellow with a reddish centre and lavender tips, 100 cm (40 in.), mid. ‘Petit Brigette’ – up-/out-facing, glossy bright yellow, 45 cm (18 in.), early to mid. ‘Skydancer’ – down-facing, creamy white with a few brown spots and a green nectary, 150 cm (60 in.), early.

‘Ivory Pixie’, another dwarf Asiatic lily bred for smaller landscapes, is only 40 cm (16 in.) high.

Pink: ‘Barber #17’ – out-facing, lavender pink and spotted, 75 cm (30 in.), mid. ‘Carol Jean’ – up-facing, rosy pink with a creamy-pink nectary and brown spots, 30 to 40 cm (12–16 in.), early. ‘Chianti’ – up-facing, pink with a green-and-white nectary and a few red spots, 90 to 110 cm (36–44 in.), early. ‘Crete’ – up-facing, purplish-pink with no spots and a white nectary, 90 cm (36 in.), early. ‘Denia’ – up-/out-facing, pink with whitish tips and throat and dark red spots, 30 to 45 cm (12–18 in.), mid. ‘Dusky Belles’ – up-facing, deep purple-pink, 90 cm (36 in.), early to mid. ‘Embarrassment’ – out-/down-facing, dusty rose-pink with dark spots, 120 cm (48 in.), early. ‘Honey Pink’ – out-/down-facing, with a pinkish-yellow overlay and no spots, 75 cm (30 in.), mid. ‘Honeywind’ – out-/down-facing, yellowish-pink with dark brown spots and frosty-pink nectaries, 70 to 100 cm (28–40 in.), early.

‘Chianti’, an up-facing pink Asiatic lily, blooms early in the season. It has a green and white nectary and a few red spots and is 90 to 110 cm (36-44 in.) high.

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‘Ikaria’ (‘Malta’) – up-facing, lavender pink with a red picotee edge and no spots, 90 cm (36 in.), early. ‘Melissa Jaime’ – out-/down-facing, creamy pink with pink tips and a few spots, 45 to 60 cm (18–24 in.), early to mid. ‘Minuette’ – up-facing, soft pink with a creamy-yellow centre and spots, 60 to 90 cm (24–36 in.), early to mid. ‘Monte Rosa’ – up-facing, dawn pink with an orange throat, 100 cm (40 in.), early to mid. ‘Pink Pixie’ – up-facing, creamy pink with pink tips and a spotted centre and green nectary, 30 to 45 cm (12–18 in.), early to mid. ‘Prairie Pink’ – out-/down-facing, pink, spotted, 100 to 120 cm (40–48 in.), mid. ‘Robinson’s Comet’ – out-/down-facing, clear red-purplepink with a deeper red centre, 90 cm (36 in.), mid to late, ‘Embarrassment’, a tall, early blooming Asiatic lily, is great for the back of the border.

tetraploid. ‘Sassy’ – out-/down-facing, pink with a dark pink nectary and a few spots, 90 cm (36 in.), early. ‘Sonata’ – down-facing, light coral-pink with darker edges, 100 cm (40 in.), mid, triploid. ‘Toscana’ – up-facing, soft pink fades to a near white, 90 cm (36 in.), mid. ‘Tropic Delight’ – up-facing, pinkish red-orange flush, 90 cm (36 in.), mid, tetraploid. ‘Tropical Dream’ – up-facing, coral-pink with an apricot centre and a few dark spots, 90 cm (36 in.), mid, tetraploid. Peach: ‘Doeskin’ – down-facing, creamy fawn with a buff throat and no spots, 75 cm (30 in.), early. ‘Honey Queen’ – out-facing, honey amber with rose-pink tips, 100 cm (40 in.), early to mid. ‘Peach Supreme’ – up-facing, light peach with a few spots, 75 cm (30 in.), mid.

A lovely down-facing Asiatic lily, ‘Doeskin’ is a creamy fawn with a buff throat and no spots. It blooms early in the season and is 75 cm (30 in.) high.

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‘Salmon Cream’ – up-/out-facing, peach-pink fading to a creamy pink with a few spots, 120 cm (48 in.), late. ‘Tiger Babies’ – out-/down-facing, large, salmon-peach with a chocolate reverse, 100 cm (40 in.), early.

White: ‘Centrefold’ – up-facing, burgundy-red brushstrokes on a white base, 90 cm (36 in.), early. ‘Cinnamon Toast’ – up-facing, creamy-white with a few grey-purple spots, the outer edges of the petals are a brilliant yellow, 90 cm (36 in.), mid. ‘Misty Eyes’ – up-/out-/down-facing, creamy-white with a small plum brushmark and a green nectary, 100 cm (40 in.), mid. ‘Mont Blanc’ – up-/out-facing, white with a few spots, 80 cm (32 in.), early. ‘Moon Baby’ – up-/out-facing, creamy-white with dark red brushmarks and a yellow orange throat and nectary, 90 cm (36 in.), mid. ‘Polar Bear’ – up-facing, creamy-white with purple spots, 75 to 90 cm (30–36 in.), early. ‘Roma’ – up-facing, creamy-white with a few brown spots

‘Moon Baby’, an Asiatic hybrid lily, is creamy white with dark red brushmarks, blooms in mid season and is well placed toward the middle of the border.

and a green nectary, 150 cm (60 in.), early. ‘Sweet Surrender’ – down-facing, creamy-white with black speckles, 90 cm (36 in.), early. Red: ‘Bold Knight’ – out-facing, red-black with dark spots, 110 cm (44 in.), mid. ‘Ed Brooman’ – out-facing, dark burgundy red-black with black spots, 90 to 100 cm (36–40 in.), mid. ‘Lovelite’ – up-facing, red with a few spots, 90 cm (36 in.), mid. ‘Mirabella’ – up-/out-facing, purple-red with yellow-green tips and nectary and dark red spots, 40 cm (16 in.), early. ‘Morden Butterfly’ – down-facing, cherry red with fine black spots, 120 cm (48 in.), mid. ‘Olina’ – up-facing, large red blooms with a heavy mass of black spots in centre, 100 to 115 cm (40–46 in.), mid. ‘Petite’ (’Petit’) – up-/out-facing, chalice-shaped, dark wine, pollen-free, very dark stems, 60 to 100 cm (24–40 in.), mid. ‘Red Carpet’ – up-facing, vivid red with no spots, 30 cm (12 in.), early to mid.

‘Olina’ is a tall, up-facing red lily with a heavy mass of black spots toward its centre.

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‘Red Velvet’ – out-/down-facing, deep red with very few spots, 120 to 150 cm (48–60 in.), late, triploid. ‘River Rouge’ – up-facing, clear red with a deeper red centre, 90 cm (36 in.), mid, tetraploid. ‘Rosefire’ – up-facing, red with a yellow blush,120 cm (48 in.), early. Longiflorum-Asiatic hybrids (LA hybrids) are interspecific hybrids between longiflorum lilies and lilies of the Asiatic group. They have similar characteristics to the Asiatics but are sturdier, have more blooms and are altogether showier. They are also more prone to colour-breaking virus, similar to that found on tulips, with streaking and mottling, for which there is no cure.

‘Red Velvet’ faces both out and down. It is a deep red triploid Asiatic lily with very few spots, tall (120 to 150 cm/ 48-60 in.), and blooms late in the season.

‘Royal Sunset’, a longiflorumAsiatic hybrid lily, is a peachy orange with dark pink tips and a few red spots.

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These have been primarily hybridized in Holland, where disease resistance is not high on the list of breeding goals. All are up-facing, about 90 cm (36 in.) in height and generally bloom in July. For xeriscape gardens, Asiatics and martagons are usually more drought tolerant and the best bet, but the following LA hybrids are also recommended. ‘Coral Fashion’ – coral-red with a few dark spots. ‘Manhattan’ – rosy salmon with no spots. ‘Moneymaker’ – purple-pink with a green nectary and a few spots. ‘Royal Dream’ – yellow-green fading to ivory-white with no spots. ‘Royal Parade’ – soft red with no spots, 100 cm (40 in.). ‘Royal Sunset’ – peachy orange with dark pink tips and a few red spots. ‘Suncrest’ – large creamy-yellow flowers with maroon spreckling (or specks).

‘Manhatten’, a longiflorumAsiatic hybrid lily, is characterized by sturdy stems, showy blooms, and lots of them.

CARE: Grow in full sun in deep, well-drained soil to which organic matter has been incorporated. Lilies are generally fairly tolerant of dry conditions but do need a good watering when first planted. They also appreciate a watering in the spring and occasionally in the summer. But for many, dry is better than wet. They are drought tolerant once established. Mulch after planting. USE: Lilies are excellent in perennial and mixed borders and

as cut flowers. Martagons have dainty, recurved, down-facing blooms often described as turkscaps. They begin blooming the last week in June and some have as many as fifty flowers per stem. They are best placed in a shady spot. ‘Amelita’ – purple-pink with spots, 100 to 120 cm (40–48 in.), early. ‘Brocade’ – orange-yellow suffused with pink, with chocolate-maroon spots, 120 to 150 cm (48–60 in.), early. ‘Dalhansonii’ – chestnut brown with a gold centre and spots, 150 cm (60 in.), early. ‘Moonyeen’ – medium pink with purple-red spots, 100 to 150 cm (40–60 in.), early. ‘Mrs R. O. Backhouse’ – yellow flushed with magenta rose

‘Brocade’ is an orange yellow martagon or turkscap lily that is suffused with pink and has chocolate-maroon spots.

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and a pink reverse, with a few red spots, 150 to 180 cm (60–70 in.), early. ‘Orange Marmalade’ – orange with no spots, pollen-free, 120 to 150 cm (48–60 in.), early. ‘Rosalinda’ – rose-pink with light red spots, 120 cm (48 in.), early. CARE: Plant in shade in well-drained soil amended with organ-

ic matter. Martagon lilies have very good disease resistance and tolerate a wide range of conditions, but they should be well watered when planted and given another good watering each spring and occasionally in summer during prolonged dry conditions. USE: Use in shaded borders; also good for cutting.

Grape hyacinth (Muscari spp.) Here is another dependable minor bulb that forms a colony that increases from year to year. The botanical name is from ‘Moonyeen’, like other martagon lilies, does better in shade and should be watered when conditions are dry.

the Greek word for musk and describes their scent. They are native to Asia. Blooming in early spring, the flowers of grape hyacinths resemble a miniature pyramid of blue-purple grapes sitting on a stalk above grassy foliage, thus the derivation of the common name. Three species are generally offered. Muscari armeniacum, from southeastern Europe and the Caucuses, is probably the hardiest species. It has dark blue flowers and is 30 cm (12 in.) high. ‘Album’ is white form. M. azureum, from Turkey, is a little shorter at 20 cm (8 in.) with sky-blue flowers. ‘Album’ is a white form. M. latifolium, from southwest Asia, is striking and unusual in that it has dark blue flowers at the bottom and paler, sterile flowers (sometimes oddly shaped) above and only one, albeit wide, leaf. It may be less hardy but is worth trying in a sheltered location. CARE: Plant in full sun or light shade in well-drained soil.

Grape hyacinths (Muscari spp.) bloom in early spring and soon form a carpet. They are ideal for rock gardens.

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USE: Use in rock gardens, the front of a border and for natural-

izing under deciduous trees or shrubs.

Puschkinia, Lebanon squill (Puschkinia scilloides, syn. P. libanotica) Unless you’re close up and on your knees, these tiny flowers are such a pale blue (with a darker blue line down the middle of each petal) that they appear almost white. A minor bulb, they are native to the Caucasus, Iraq and Lebanon. They were named after a Russian chemist and botanist, Count Mussim-Puschkin, who collected them. Only 15 cm (6 in.) in height, with two to three narrow leaves, they are another carpeting type of bulb and will gradually form a colony. ‘Alba’ is a white form. CARE: Place in full sun or partial shade and well-drained soil. USE: Use in rock gardens.

Siberian squill (Scilla siberica) These small bulbs have naturalized in my lawn of their own volition. The genus name is from the Greek skilla, meaning seasquill, an old-fashioned houseplant to which Scilla is related. Siberian squill is native to Iran, Russia, Ukraine and Turkey,

Puschkinia (Puschkinia scilloides), a dainty minor bulb of only 15 cm (6 in.), grows well in full sun or partial shade.

hence the species name, sibirica. Sometimes called bluebell, they are one of the earliest harbingers of spring, producing blue, down-facing flowers in May above grassy, 15 cm (6 in.) foliage. Given moderately favourable conditions, they soon colonize through reseeding. ‘Alba’ is a white form. ‘Spring Beauty’ is darker, taller and more robust. S. var. taurica is a more intense blue. CARE: Plant in full sun or partial shade in well-drained, humusy

soil. USE: Excellent in rock gardens and under deciduous trees.

Tulip (Tulipa spp.) Tulipa is from the Turkish tulbend, a turban, a reference to the form of the flowers. Native to the Near East, they were cultivated and hybridized in Turkish gardens for centuries prior to their introduction to Holland, circa 1593 via the garden of Carolus Clusius, a professor of botany at the University of Leiden. They were stolen from his garden and soon became very popular, appearing in gardens all over Holland. By the

Siberian squill (Scilla siberica), one of the earliest spring bulbs, are excellent for rock gardens.

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1630s, “Tulipmania” was in full force in Holland. Amid much speculation, enormous prices were paid for a single bulb, many with unusual striping or mottling. Unfortunately, these bulbs were not long lived and many fortunes were lost. It was later discovered that both the unusual colouring and early demise of these bulbs were due to a virus. Nothing is more enticing in September than garden centre shelves full of plump tulip bulbs with their implied promise of spring bloom. The harsh reality is that many of these are not reliably hardy on the prairies. Some will come through their first spring and then fail to appear in subsequent years. Others may not appear at all. Of the approximately five thousand tulip varieties available, The tarda tulip (Tulipa tarda) is one our hardiest and most drought tolerant bulbs, yet it’s not widely available. It’s early, adaptable and soon multiplies.

the divisions, species and cultivars listed below are among your best bets for reliable spring colour on the prairies. They combine drought tolerance, hardiness and a more perennial habit than most. Darwin hybrids are derived from crosses of single late tulips and what were once known as Darwin and Cottage tulips

Tulipa greigii hybrids are characterized by attractive mottled foliage and large cup-shaped early blooms.

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with Tulipa fosteriana and other botanical species. Darwin hybrids are tall plants with single flowers of good size and colour on sturdy stems. ‘Appeldoorn’ – red with persimmon orange edges and interior, 55 cm (22 in.). ‘Beauty of Appeldoorn’ – yellow washed with orange, 50 cm (20 in.). ‘Golden Appeldoorn’ – golden yellow, 55 cm (22 in.). ‘Golden Oxford’ – golden yellow, black interior base, 55 cm (22 in.). ‘Oxford’ – scarlet flushed with red, 55 cm (22 in.). ‘Parade’ – red, large black interior base edged with yellow, 45 cm (18 in.). ‘Pink Impression’ (‘Spring Pearl’) – large pink-rose flower, 55 cm (22 in.). From central Asia, the T. fosteriana hybrids have large flowers with wide petals and shiny foliage on stems 30 to 60 cm (12–24 in.) in height. All are early flowering. They are hybrids

‘White Emperor’ (also listed as ‘Purissima’) is a Tulipa fosteriana hybrid. Pure white, it is early flowering and about 40 cm (16 in.) high.

of T. fosteriana and T. greigii or T. kaufmanniana. ‘Orange Emperor’ – large, dark orange, early, 45 cm (18 in.). ‘Pink Emperor’ – pink with pearl sheen, 35 cm (14 in.). ‘Red Emperor’ (‘Madam Lefeber’) – red with black centre, 40 cm (16 in.). ‘White Emperor’ (‘Purissima’) – white with yellow interior, 40 cm (16 in.). ‘Yellow Emperor’ – yellow, 40 cm (16 in.). T. greigii hybrids are short and multi-stemmed, with large, cup-shaped, early blooms. From central Asia, the species is red orange and the distinctive foliage is characterized by purple-and-green striping or mottling. ‘Red Riding Hood’ – carmine red and scarlet, 35 cm (14 in.). ‘Toronto’ – salmon-pink, 30 cm (12 in.). T. praestans hybrids, from central Asia and Turkestan, are 20 to 30 cm (8–12 in.) in height with multiple flowers in mid-spring. ‘Fusilier’ – vermillion red-dark orange, glaucous greygreen foliage, 25 to 30 cm (10–12 in.). ‘Van Tubergen’ – large orange scarlet flowers, 25 cm (10 in.).

Tulipa praestans hybrid tulips, originally from central Asia and Turkestan, have multiple flower stems and generally red flowers. They bloom in mid-spring.

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Tulipa tarda,

G

from central Asia, is 10 to 15 cm (4–6 in.)

in height, with yellow, white-tipped petals. It very quickly forms low colonies and is truly perennial. No garden should be without it! T. urumiensis,

G

native to Lake Urumia in Iran, is also a

low colonizer, 12 cm (5 in.) in height with yellow petals. CARE: Tulips do best in full sun and good drainage. Purchase

them as soon as they become available in the fall and plant them immediately. Water well, mulch and hope for an early and continuous snow cover – their best insulation! USE: They add spring colour to a perennial or mixed border

and are often used in annual beds. Species, such as T. tarda and T. urumiensis, are shorter and well adapted to rock gardens.

Tulipa urumiensis, a dwarf, bright yellow species tulip from Iran, is hardy, drought tolerant, long lived and soon forms colonies. Unfortunately, it is seldom available to prairie gardeners. It’s well worth seeking out.

Fosteriana hybrid tulips are characterized by large flowers with wide petals and shiny foliage.

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PART 3

Appendices “It seems inevitable that in the matter of names there will always be a conflict of interest between botanists (who want to get it right) and gardeners (who also want to get it right, but to have it stay the same.)” — CHARLES ELLIOT



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G

G

Russian olive

wolfwillow

G

G

Elaeagnus angustifolia

Elaeagnus commutata

diervilla, dwarf bush honeysuckle

Diervilla lonicera

hawthorn

broom

G

cotoneaster

Cytisus spp.

Crataegus spp.

G

hazelnut

Corylus spp.

Cotoneaster spp.

red-osier dogwood

Cornus sericea

caragana, pea shrub

‘Delta’ hackberry

G

Japanese barberry

sagebrush

chokeberry, aronia

bearberry, kinnikinnick

leadplant and false indigo

saskatoon berry

Manitoba maple, box elder

Amur maple, ginnala maple

subalpine fir

COMMON NAME

Celtis occidentalis

Caragana spp.

Berberis thunbergii

Artemisia spp.

Aronia melanocarpa

G

G

Arctostaphylos uva-ursi

Amorpha spp.

Amelanchier alnifolia

G

G

Acer negundo

Acer ginnala

Abies lasiocarpa

G= extreemly drought tolerant

BOTANICAL NAME

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