water-smart garden design - australia

Contents

Introduction 5

Chapter 1 Water-smart Garden Design | 11Work with Your Climate | 11Reduce the Amount of Lawn | 15Designing the Lawn | 22Create Watering Zones | 23

Chapter 2 Soils | 28What Type of Soil Do You Have | 28How Plants Gain and Lose Water | 36Improving Your Soil | 37

Chapter 3 Water-guzzlers | 41Lawns and their Alternatives | 41Vegetable Gardens | 46Annuals | 48Fruit Trees | 49Weeds | 50Plants in Containers | 50

Chapter 4 Waterwise Plants | 54The Plant Descriptions | 58High Drought-tolerant Plants | 61Medium Drought-tolerant Plants | 79Low Drought-tolerant Plants | 110

Chapter 5 Mulching | 122Countering Mulch's Downside | 122Before You Mulch | 123How to Mulch | 123Selecting a Mulch | 124

Chapter 6 Efficient Watering | 136Avoid Wasting Water | 136Harvest Your Own Water | 141Using Greywater | 148Watering Techniques | 153Installing a Watering System | 158

Useful Resources 170

Index 171

Published in Australia in byReed New Holland

an imprint ofNew Holland Publishers (Australia) Pty LtdSydney • Auckland • London • Cape Town

14 Aquatic Drive Frenchs Forest NSW 2086 Australia218 Lake Road Northcote Auckland New Zealand86 Edgware Road London W2 2EA United Kingdom80 McKenzie Street Cape Town 8001 South Africa

Published in 1993 by Reed Books as Water-saving GardeningRevised in 1995

Third edition published 2004

Copyright © 1993, 2003 in text:Kevin WalshCopyright © 1995, 2003 in photographs: Lauretta Zilles and

as creditedCopyright © 2003 New Holland Publishers (Australia) Pty Ltd

All rights reserved. No part of this publication may bereproduced, stored in a retrieval system or transmitted, in anyform or by any means, electronic, mechanical, photocopying,recording or otherwise, without the prior written permission of

the publishers and copyright holders.

National Library of Australia Cataloguing-in-Publication Data:

Walsh, Kevin, 1957- .Waterwise gardening.

3rd ed.Includes index.ISBN 1 877069 01 9.

1. Xeriscaping - Australia. 2. Xerophytes - Australia. 3.Landscape gardening - Water conservation - Australia. I.Walsh, Kevin, 1957- Water-saving gardening : water-wiseplants and practices in Australia. II. Title.

635.0994

Publisher: Louise EgertonEditor: Jennifer LaneDesign & Illustration: saso content & designProduction Manager: Linda BottariReproduction:Printer:

[Any picture captions for cover and prelims can be includedhere]

DISCLAIMER: Neither author nor publishers take any responsibility for any results, effects or outcomesconnected with any advice or method provided in this book, however caused.

Published in Australia in 2009 byReed New Holland

an imprint ofNew Holland Publishers (Australia) Pty LtdSydney • Auckland • London • Cape Town

Unit 1, 66 Gibbes Street Chatswood NSW 2066 Australia218 Lake Road Northcote Auckland New Zealand86 Edgware Road London W2 2EA United Kingdom80 McKenzie Street Cape Town 8001 South Africa

First published in 1993 by Reed Books as Water-savingGardening, Revised in 1995, Third edition published 2004

Copyright © 1993, 2004, 2009 in text: Kevin WalshCopyright © 1995, 2004, 2009 in photographs: Lauretta Zilles

and as creditedCopyright © 2009 New Holland Publishers (Australia) Pty Ltd

All rights reserved. No part of this publication may bereproduced, stored in a retrieval system or transmitted, in anyform or by any means, electronic, mechanical, photocopying,recording or otherwise, without the prior written permission of

the publishers and copyright holders.

National Library of Australia Cataloguing-in-Publication Data:

Walsh, Kevin, 1957-Waterwise gardening / Kevin Walsh.4th ed.9781877069642 (pbk.)Includes index.

Xeriscaping--Australia.Xerophytes--Australia.Landscape gardening--Water conservation--Australia.

635.0994

Publisher: Louise EgertonEditors: Jennifer Lane and Diane JardineDesign & Illustration: saso content & design andHayley Norman

Production Manager: Olga DementievPrinter: SNP/Leefung Printing Co. Ltd (China)

Cover photographs, clockwise from top left-hand corner:front One-sided bottlebrush, Dusky Correa, Kaffir Lily, Stocksback Japonica

Contents

Introduction 5

Chapter 1 Water-smart garden design | 11Work with your climate | 13Reduce the amount of lawn | 17Designing the lawn | 24Create watering zones | 25

Chapter 2 Soils | 30What type of soil do you have? | 30How plants gain and lose water | 38Improving your soil | 39

Chapter 3 Water guzzlers | 43Lawns and their alternatives | 43Vegetable gardens | 49Fruit trees | 50Annuals | 52Plants in containers | 53

Chapter 4 Waterwise plants | 57Plant descriptions | 63High dry-tolerant plants | 65Medium dry-tolerant plants | 85Low dry-tolerant plants | 115

Chapter 5 Mulching | 128Countering mulch’s downside | 128How to mulch | 129Selecting a mulch | 132

Chapter 6 Efficient watering | 145Avoid wasting water | 145Harvest your own water | 150Using greywater | 158Watering techniques | 165Installing a watering system | 172

Useful resources 185

Index 186

71115_CTP_001-029revised_DJHNv6_03:71115_CTP_001-027 22/5/09 12:42 PM Page 4

IntroductionAustralia is often called ‘the driest inhabited country’, yet for too long garden-

ers have been trying to defy the climatic reality of this land—one which is far

removed from the British model on which our gardens and gardening practices

are largely based. The time has come to discard this ‘horticultural cringe’ and

to make gardens that respond to the true nature of the Australian climate.

It is easy to create a garden that is waterwise and environmentallyfriendly, yet full of colour, interest and variety. All we have to do is toadopt six vital principles.These are:

1 Reduce areas of lawn

2 Group plants according to their water needs

3 Use dry-tolerant plants

4 Maintain the garden

5 Use mulch

6Water efficiently

Any one of these six vital principles will help save water, but if youcan incorporate all six in your garden you will really begin to noticesignificant savings in your water bill.

AcknowledgmentsMy thanks go to a number of people for their help with this edition andongoing support for this book in its various forms over the past15 years.These include all at New Holland including Diane Jardine forediting and Hayley Norman for the map drawing;Lauretta Zilles for pho-tography; Debbie Golvan; Jenny McSwain; Robyn and Frank Lewis; andJimmie Morrison. The illustration on page 10 is based on that of theBureau of Meteorology and is used with permission.Thanks to all whohelped with earlier editions and whose plants or gardens arephotographed. In particular, a special mention to Lauretta, Natalie andCallan for their ongoing support and patience. In a country as

dry as Australia itmakes sense to

design our gardensto the conditions.

A waterwise gardencan be as colourful andvibrant as any garden;it just uses less water.

Key to symbols used in this book

Throughout this book plants are listed by their common name and thenalphabetically by their Latin name, then by their level of dry tolerance.

Reduce lawn

Group plants

Dry tolerant

Maintenance

Mulch

Water efficiently

High dry tolerance

Medium dry tolerance

Low dry tolerance

Water guzzler

High heat tolerance

Medium heat tolerance

Low heat tolerance

M

H

L

H

M

L

GDid you know...By following the tipsin this book you couldeasily cut your garden’sconsumption of drinkingwater in half, or evenmore.


Reducing water use does notmean gardens should becomedeserts of pebbles sparsely plantedwith cacti.With a little imagination,careful planning and preparation youcan create an extremely colourfulgarden with low water require-ments. Such gardens can be formalor informal, modern or traditional,and designed to fit in with the condi-tions of a particular location.

Furthermore, designing a water-efficient garden does not rule outusing water as a feature. Indeed, arecirculating pump will use very littlewater. The cooling effect of waterfeatures adds to our enjoyment of anoutdoor lifestyle in this hot,dry land.

The economic benefitsMost areas of Australia now operateunder a ‘user pays’ system for household water.

This system is believed to better reflect the real cost of water.Although it differs a little between states and regions, it is generallybased on a two-part system.The first is a ‘service fee’ for getting water toyour door.You pay this fixed amount on each water bill whether you usethe water or not.The second part is the ‘usage fee’—the more you use,the more you pay. It is this second part where most households can savemoney simply by reducing the amount of water used in the garden.

It has been estimated that between one-quarter and one-half of alldomestic water use is for gardens. The potential for reducing thisamount—and your water bill—is enormous.

Introduction 9Waterwise Gardening8

The environmental benefitsOne significant benefit of a waterwise garden is the protection of ourenvironment. If we don’t curb our rising water consumption soon,authorities will need to create additional dams and weirs,which in turnmeans altering natural watercourses and submerging large areas ofnative vegetation. Saving water in the garden will help reduce the needfor new water storage facilities.

Collecting and using rainwater in our gardens could provide up to40 per cent of our garden’s water needs, and is one positive way toreduce the amount of water we are taking out of our natural environ-ment. Some estimates also suggest that using ‘greywater’ in the gardencould reduce a household’s total consumption of drinking-quality waterby up to 20 per cent.

Our current garden-watering practices result in large amounts offertilisers and salts leaching into waterways, causing pollution, salin-ity and outbreaks of blue-green algae. Waterwise gardening canlargely prevent this by eliminating the over-watering which flushesthese materials into our groundwater.The use of soil improvers, suchas compost, can also help to bind these nutrients in the plants’ rootzones. Practices such as composting not only improve the fertilityand water-retaining capacity of our soil, but reduce the volume ofwaste going into landfills.

The horticultural benefitsA waterwise garden requires less maintenance, not only because it usesless water (which reduces the time you spend watering), but alsobecause many techniques used to reduce water demands also reducemaintenance requirements in general. For example, reducing the size ofan area of lawn reduces water use and results in less time spentmowing. Using mulch reduces evaporation from the soil but also

reduces weed growth, and so on.The lower maintenance properties of a water-

wise garden make it an ideal approach forcommercial and industrial properties, flats andunits,weekenders and holiday homes.

A waterwise garden is also a healthy garden.The soil is improved and plant stress is minimisedthrough appropriate plant selection, maintenanceand watering.

Water features bring a cooling effect to a

garden, and are water efficient if the water

is recirculated by a pump.

Did you know...More garden plantsprobably die fromover-watering thanfrom lack of water.


Where Australia’s water comes fromAustralia is the driest inhabited continent in the world:more than 70 percent of the continent receives less than 500mm of rainfall in an averageyear.Many areas, too,have long seasons where little or no rain falls.

The majority of our water is collected from surface sources—typicallyrun-off that is collected and held in huge storage dams and reservoirs.Thewater is then piped from these catchments to major population centres.Most Australian capital cities rely on such systems for their water, exceptPerth (which relies heavily on groundwater) andAdelaide (which utiliseswaterflow from the Murray River,catchment facilities and groundwater).

Increasingly, authorities are turning to desalination as a source offresh water, with all mainland states actively considering or installing

Waterwise Gardening Introduction10 11

Broome

Kalumburu

Katherine

Weipa

Kowanyama

NormantonTennant

Creek

Geraldton

Newman

Telfer

Giles

Halls Creek

Oondnadatta

Cook

Port Lincoln

Port Augusta

Mildura

Horsham

Orbost

DubboCo�sHarbour

Cape Grim

Strahan

Kalgoorlie-Boulder

Wiluna

Townsville

Mackay

Mount Isa

Summer DominantMarked wet summerand dry winter

Wet winter and lowsummer rainfall

Wet summer andlow winter rainfall

Marked wet winterand dry summer

Uniform Rainfall

Low Rainfall

Summer Uniform

Winter Winter Dominant Arid

Main climatic zones of Australia (based on rainfall)

Understanding when rain occurs in your area will help you plan your waterwise garden. What is El Niño?El Niño is a phenomenon often associated with droughts. The waters off the westerncoast of South America are usually cool with high surface pressures. The air fromthis area travels on the easterly trade winds across the Pacific Ocean towards thewarmer tropical waters and lower atmospheric pressure north of Australia. Thestrength of this circulation is measured by an index called the Southern OscillationIndex, which is the pressure at Tahiti minus the pressure at Darwin.Occasionally, unusually warm waters off the South American coast disrupt the

circulation, giving weaker trade winds and resulting in less moisture being carriedover the ocean to Australia. When this happens and the Southern Oscillation Index isnegative, it is likely that some parts of Australia might have lower than averagerainfall and possibly drought.

desalination plants.Unfortunately there are serious environmental reper-cussions from desalination, including the disposal of the waste productsand brine water which are by-products of the process. Desalination isalso a huge consumer of electricity, therefore further adding to thegreenhouses gases which are largely responsible for climate change.

What the future holdsOur water supplies are under increasing pressure. Australia’s popula-tion continues to grow and yet our water supplies are actuallydwindling. Climate change means that for most parts of Australia therewill be higher temperatures leading to greater evaporation. Generallyspeaking, rainfall will be reduced and when it does come it will bemore often in heavy downpours that tend to run off the surface ratherthan soak into the ground.

Additional demands for agriculture and industry to service the expand-ing population also put pressure on the little we have, and further impacton the natural environment.The El Niño phenomenon is not always anaccurate indication of when drought will occur or for how long.

We need to start doing something immediately to conserve this mostprecious and finite of resources on which all life depends.We can all doour bit by saving water in the house and, in particular, in the garden.Withthe six vital principles of waterwise gardening explained in this book,wecan create bright,attractive,economical and low-maintenance gardens.

Bureau

ofMeteo

rology

Major seasonal rainfall zones of Australia


Chapter 1

Water-smart garden designMost Australian gardens are not designed with water use in mind. This chapter

explains the process of designing—or redesigning—a garden to make it more

water efficient. Along the way it puts two principles of waterwise gardening into

practice: limit areas of lawn and group plants according to their needs.

Those contemplating making a new garden have the opportunity toapply the principles ‘from the ground up’, and get it right from thestart. Long-established gardens can also be made much more waterefficient, however, by making simple changes to the design.

To design a waterwise garden you must take into consideration thepeculiarities of your site. Basically, this means taking a critical look atvarious aspects of your garden, including existing features, proposedinclusions, the way you intend to use the garden and any other aspectssuch as the slope of the ground, soil type and, of course, climate.

Work with your climateTo design a garden that makes best use of the advantages of your site,and at the same time reduces the impact of negative factors, you needto understand the elements of climate that influence your garden.Climate is divided into three categories:macroclimate,mesoclimate andmicroclimate.Macroclimate is the climate of a large area, such as a met-ropolitan city or provincial district,while mesoclimate is the climate ofa more specific part within that general area. Microclimate is theclimate of small areas, such as those found within a property boundary.

The macroclimate of your area will broadly influence your plant selec-tion and water use in the garden.Things to be aware of include averagetemperatures at different times of the year, periods of low rainfall, occur-rence of frost,proximity to the coast (and therefore salt-laden winds) andso on.Microclimate, however, has the most bearing on the layout of yourgarden,and this is particularly true for established houses and gardens.Four-o’clock Flower


Windbreak plantingHot winds dry out lawns and gardens rapidly,and make your garden muchless enjoyable. A windbreak planting can reduce the impact of thesewinds.(It may also change the amount of sun getting to parts of the garden,however,so bear in mind the effect this will have on plants in the vicinity.)

Coastal exposureGardens situated close tothe sea are often particularlywindy. This wind carriessalts onto plant foliage,which not all plants tolerate.

Understanding your microclimateFactors affecting microclimate include the orientation of the property tothe sun, the direction and temperature of the prevailing wind, the influ-ence of nearby buildings, topography, the amount of reflective surfaces,and the spread and foliage type of existing trees.Observing these factorswill help you to either take advantage of the circumstances or put inplace appropriate steps to overcome the negative ones.

The southern side of a house and areas underneath trees often havea microclimate that is shady and less exposed to hot, drying winds.While lawn won’t grow well in these places, they are often great spotsfor shade-loving plants. Because such areas do not dry out so rapidly,they make a good watering zone for plants of low dry tolerance.

The north and west sides of the house are generally hotter and moreexposed to the elements.This could be a good spot for a lawn or veg-etable garden, as these need plenty of sun.

Sometimes you may be able toadapt the microclimate of yourgarden.For example, if your outsidesitting area is north of the houseand you wish to create shade tomake it pleasant in summer, theaddition of shade sails or a timberpergola with a deciduous climberwill help achieve this.

Waterwise Gardening Water-smart garden design14 15

This sunny

and exposed

area is planted

up with sun-

loving plants.

Trees for windbreaks

Monterey Cypress Cupressus macrocarpa HYate Eucalyptus cornuta HCoral Gum Eucalyptus torquata HNorfolk Island Hibiscus Lagunaria patersonia HOlive Olea europaea HAleppo Pine Pinus halepensis HCork Oak Quercus suber HPeppercorn Tree Schinus molle var. areira HSydney Golden Wattle Acacia longifolia MGolden Blackwood Acacia melanoxylon MCoast Banksia Banksia integrifolia MSilky Oak Grevillea robusta MCoastal Tea Tree Leptospermum laevigatum MBrush Box Lophostemon confertus MOsage Orange Maclura pomifera MFlaxleaf Paperbark Melaleuca linariifolia MNew Zealand Christmas Tree Metrosideros excelsa MStone Pine Pinus pinea MHolm Oak Quercus ilex MLillypilly Acmena smithii L

This grape-covered pergola creates

a shady sitting area north of the house.

Norfolk Island

Hibiscus

Coastal gardens often have to contend

with high winds, and windbreaks can

help reduce the negative effects.


water-smart garden design - australia

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