Waterwise Guide to Gardening: A Guide to Saving Water in Established Gardens

1. O
ET
UID
EG
WIS
ING
TER
DEN
WA
THE
A guide to
GAR
saving water
in established
gardens.
Edited by
John Colwill
local gardening
expert
www.watercorporation.com.au

2. The Waterwise
Gardening

3. Guide
In the metropolitan area
approximately 60% of annual
water consumption goes on
watering lawns and gardens.
In summer this figure rises
to almost 80%.
This booklet contains up-to-date
information on techniques and
practises that help save water
in your garden even if it has
been established for years.
If you are starting a new garden
from scratch, you will find a
wealth of information that will
let you plan and install a garden
which will cope with our
climate and meet your needs
without wasting water.

4. Contents
Introduction ................................................................................................1
Garden design............................................................................................2
Before you plant.......................................................................................3
Soil improvement..............................................................................3
Soils for containers ..........................................................................5
What to plant ............................................................................................5
Lawns .......................................................................................................5
Methods of planting ........................................................................6
Other garden plants........................................................................7
Watering zones...............................................................................11
How to water .........................................................................................12
Sprinklers ............................................................................................12
Micro-irrigation................................................................................13
Choice of equipment...................................................................13
Pressure ...............................................................................................14
How much water to apply.......................................................14
Making the most of Watering Zones.................................15
Watering Lawns..............................................................................16
Operation...........................................................................................16
Waterwise lawn management................................................17
Watering shrubs and perennials ...........................................18
Watering fruit trees......................................................................19
Watering pot plants .....................................................................20
Watering hanging baskets .........................................................21
Watering bedding plants ...........................................................21
Watering vegetables.....................................................................21
Irrigation .....................................................................................................22
After you plant .......................................................................................22
Lawn maintenance.........................................................................22
Mulching gardens............................................................................23
Mulching material...........................................................................24
Applying mulches ...........................................................................24
Changing an established garden ............................................25
How Waterwise is your garden?...........................................27

5. Introduction
In Perth and the Southwest of Western Australia we
have become used to enjoying a mediterranean climate
where the winters are mild and wet and the summers
long, warm, hot and dry. However, most of our gardens
and garden practices are still based upon northern
European models where the climate is cooler and wetter
and the plants more delicate. As a result we have had to
use a lot of water to maintain the exotic gardens and
the plants that we have become accustomed to growing
since the first European settlers arrived here.
However, because there has been a dramatic decrease
in the rainfall which charges our dams and
groundwater resources, and a steady growth in
population, there is an urgent need to reduce the
amount of water that is used. The greatest potential
for saving water is in the garden.
Saving water does not have to mean ‘browning off ’.
Most gardeners regularly over-water. In these cases
reducing water consumption will have little or no effect
at all, sometimes it may even improve the garden.
1

6. Garden design
The average garden is a mix of both water consuming
areas such as lawn, flower beds, borders and shrubberies,
and hard or dry surfaces such as paving, sheds and pathways.
When planning a new garden, or remodelling an old one,
consider your needs like:
• Utility spaces such as clothes drying, compost and
storage areas.
• Outdoor living spaces such as courtyards, barbecues
and seating.
• Special needs such as a vegetable garden, swimming
pool, etc.
• How much time you have for garden maintenance.
• How much money you wish to spend on the garden.
The general principles of saving water through garden
design are to:
• Maximise the use of non-planting treatments such as
paving and mulches whilst at the same time being
aware of the risk of creating hot spots due to large
areas of unshaded paving.
• Manage lawn areas correctly so as to minimise their
water requirement and not pollute groundwater
through excess fertilising. Lawn areas form part
of our daily lives for recreation and appearance
purposes.They should be designed to fit into an
overall waterwise garden concept with the total area
kept to a size which is consistent with functional and
aesthetic requirements.
2

7. • Keep planted areas dense and consolidated. Sparse
scattered plants are more difficult to water efficiently
than those in defined areas.
• Make use of windbreaks, pergolas, screens, lattice,
shadecloth and vines to shelter the house, outdoor
living areas and plants.
• Prepare the soil before planting to ensure that plants
can make the most of the water which is applied.
• Choose plants which have a low water demand.
• Group plants in such a way as to allow for efficient
watering.
• Install a watering system that is both efficient and
flexible.
• Monitor and adjust the amount of water that is
applied on a regular basis.
Before you plant
Soil improvement
Adding organic matter to the soil improves both its
moisture and nutrient holding capacity.This means that
less water and fertiliser have to be applied and that
these smaller amounts are then available for a longer
period. As well as saving on water and fertiliser,
there is better plant growth with less stress
in-between waterings.
It is particularly important to improve the top 15-20cm
of soil where a plant’s feeder roots can be found.
Old animal manures, compost and proprietary products
3

8. are ideal soil improvers. Mix them in equal parts with the
garden soil prior to planting using the following areas as
a guide. Generally the bigger the area prepared,
the better the long term result.
• Shrubs, groundcovers and climbers – 30cm in depth
and up to half a metre across.
• Trees – 40cm deep and 1 metre across
• Bedding plants – 25cm deep for the whole bed.
• Lawns – 15-20cm deep for the whole area.
A common problem in sandy soils, when they dry out,
is the development of non-wettable characteristics.
Water applied to these soils simply pools on the surface
before eventually making its way down through one or
two spots.The bulk of the soil remains dry.
Non-wettable soils are particularly noticeable in
containers but are also a significant problem in lawns
where they can lead to brown dry patches developing.
A regular application of a soil wetting agent in spring is
recommended. Always water the material in immediately
and thoroughly. If the first application does not seem to
work, apply a second. Soils which are particularly prone
to the problem may need a second treatment in summer.
4

9. Soils for containers (including hanging baskets)
Choose the best quality potting mix you can afford
preferably one approved by the Australian Standards
Association.
The water and nutrient hold capacity of potting mixes
can be further enhanced by the use of water absorbent
polymers. Some potting mixes may already contain them.
Most plants are now grown in soil-less mixes which
quickly becomes non-wettable. One easy way to treat
container grown plants is to dip the whole pot into a
larger container of prepared strength wetting agent.
What to plant
Lawns
• Over a period of three Perth summers, turf research
trials by the University of Western Australia indicated
that a healthy lawn can be maintained by selecting
from a range of warm season lawn grasses suited to
our hot summer climate.
• Warm season grasses required significantly less water
than cool season grasses.
• The turf trials also indicated that warm season grasses
have an excellent capacity to recover after periods of
low water supply, whereas cool season turf species did
not recover.The research substantiated the Water
Corporation’s advice that a standard drink of 10mm
applied three times a week provides the most optimal
growing conditions in Perth for a correctly maintained
warm season lawn.
5

10. • During the peak summer period, there was some
deterioration in the colour of kikuyu but only slight
decreases in other warm season grasses. However,
they all recovered in autumn. During the same period,
the cool season grasses went brown and did not
recover. The table below details the research findings.
Variety Water Heat Drought
Use Tolerance Tolerance
Warm Season
Couch Types Low Excellent High
Buffalo Low Excellent High
Saltene Low Excellent High
Kikuyu Low Excellent High
Cool Season
Ryegrass High Poor Fair
Tall Fescue High Fair Medium
Methods of planting
There are three ways to establish a new lawn: by roll-on,
by runners, or by seed. Warm season grasses are grown
from roll on or runners.
Rolls of instant turf are the most water-efficient means
of lawn establishment. Runners require large quantities of
water to establish and should be planted only in spring.
Instant turf requires daily watering for the first four
weeks until a good root system is established and then
the lawn can cope with the stress of hot weather.
6

11. Most seed grasses are cool season varieties that are
not drought tolerant and perform badly in Perth’s hot,
dry summers.
Other garden plants
An average suburban garden may contain a range of
plants which have their origins in many different parts
of the world.
Some might come from tropical rainforests where light
is limited, rain heavy and frequent and the atmosphere
protected and humid. Such plants have not had to
develop any mechanisms to make them water-efficient
or protect them from drying winds.
Other plants may come from northern temperate
regions where it is cooler and slightly less humid and
they don’t have to cope with high temperatures.
Yet others might have originated in harsh desert
conditions where their very survival depends on
harvesting every single drop of water and storing it
for later use.
A large number of our garden plants have their origins in
Australia.Those of local origin are perfectly adapted to
our climate having evolved in it over millions of years.
To allow for efficient watering, this diverse range
of ornamental garden plants has to be divided into
three groups according to their need for water.
7

12. These groups are:-
• One Drop Plants, the most efficient users of water,
which only need occasional watering over summer.
Perhaps once every two weeks or longer.
• Two Drop Plants, less efficient but still reasonably
tough which need to be watered every 3 to 7 days
in summer.
• Three Drop Plants, which use a lot of water and need
to be watered every 1 to 2 days.
Some examples of the ‘Drop’ rating of plants are
given on the pages to follow. A full database of
commonly grown ornamental plants in WA can
be found on the Water Corporation website at
www.watercorporation.com.au/savewater. For additional
information and guidance on waterwise plant selection
visit a Waterwise Garden Centre.To find one near you
call the Waterwise Helpline on 1300 369 645.
8

13. Examples of One Drop Plants
CLIMBERS PERENNIALS
Bougainvillea Agave
Convolvulus Anigozanthos
Hardenbergia comptoniana Beaucarnea recurvata
Kennedia Conostylis candicans
Muehlenbackia complexa Crassula
Rosa banksia Echium fastuosum
Sollya Gaura
Stigmaphyllon ciliatum Gazania
Tecomaria capensis Kalanchoe
Lavandula
GROUNDCOVERS Vinca
Aptenia cordifolia Yucca
Banksia
Grevillea SHRUBS
Hemiandra pungens Acacia
Myoporum parvifolium Adenanthos
Osteospermum Artemisia
Phyla nodiflora Ceanothus
Sedum Chamelaucium
Stachys Cistus
Coprosma
Cordyline australis
Euphorbia pulcherrima
Lagerstroemia
Lantana
Melaleuca
Pimelea
Plumbago
Polygala
Raphiolepis
Rosemarinus
9

14. Examples of Two Drop Plants
CLIMBERS PERENNIALS
Antigonon leptopus Agapanthus
Hedera Anigozanthos
Lonicera Cerastium tomentosum
Pandorea Dampiera
Pelargonium peltatum Dianthus
Rosa Climbing types Dietes
Solanum Hemerocallis
Vitis Pelargonium
Wisteria Phormium
GROUNDCOVERS SHRUBS
Ajuga reptans Abelia
Alternanthera Azalea
Grevillea – Cultivars Bauhinia
Juniperus Buddleia
Rosa – Groundcover types Buxus
Scaevola aemula Caesalpinia
Thymus Callistemon
Verbena Camellia japonica
Camellia sasanqua
Chamaecyparis
Coleonema
Euryops pectinatus
Gardenia
Hebe
Ilex
Prostanthera
10

15. Examples of Three Drop Plants
CLIMBERS PERENNIALS
Clerodendron Begonia
Jasminum Chlorophyton
Passiflora Clivia miniata
Quisqualis indica Ferns
Stephanotis floribunda Impatiens
Thunbergia grandiflora
SHRUBS
GROUNDCOVERS Acalypha
Arenaria montana Acer
Sagina Boronia
Soleirolia soleirolii Clerodendron
Fuchsia
Hydrangea
Watering Zones
A typical garden bed may contain a mix of two or three
different Drop-rated plants.They may look nice together
but such a diverse mix can lead to a lot of water
wastage. Knowing the water needs of each plant allows
you to group the plants together, like with like. A water
efficient garden will be planted into areas, or Watering
Zones, each of which contains only plants with the same
Drop Rating. Only when the plants are grouped in this
way can they be watered efficiently.
11

16. How to water
No matter whether you are watering your garden from
the mains water scheme or by a private bore it is
important to apply the water as efficiently as possible
through a well designed and maintained irrigation system.
A properly designed automatic system will use less water
than a manually operated system.
By choosing a Waterwise Garden Irrigator you can be
sure that you are getting the best waterwise irrigation
advice available. Waterwise Garden Irrigators are
endorsed by both the Water Corporation and the
Irrigation Association of Australia.They can help you
design and install your irrigation system to water efficient
standards.To find your nearest Waterwise Garden
Irrigator visit www.watercorporation.com.au or call the
Waterwise Helpline on 1300 369 645.
Sprinklers
Overhead sprinklers should only be used on broad areas
which are densely planted.
Choose sprinklers that produce coarse sprays of large
droplets that are less prone to wind drift.
Use good quality sprinklers which have matched
precipitation rates. i.e. they all put out the same amount.
Cheap sprinklers often vary enormously in their output.
Uneven distribution will cause some areas to be
overwatered while others are underwatered.
12

17. Micro-irrigation
Micro-irrigation is suitable for most areas of the garden,
especially general garden beds, shrubberies, pot plants and
hanging baskets.These systems are flexible, low cost, easy
to install and allow for precise delivery and placement of
water to the root zones of individual plants.Various types
of emitters are available including a full range of micro-
sprays, mini sprinklers and fixed and variable drippers.
All micro systems should begin with a pressure or flow
control device. If this is not installed the emitters will not
work efficiently and the joints may burst under excess
pressure.These vital components are often not on display
at irrigation/hardware stores. Be sure to ask for one.
Micro-irrigation emitters are very fine and clog easily,
so lines to micro sprays and drippers should incorporate
an in-line filter.
For consistent performance it is best to use recognised
brand name products.
Choice of equipment
• Use a good quality controller which has the ability to
run separate programmes for different garden areas
or Watering Zones.
• The controller should be placed under cover in an
easily accessible site.
• Gutter mounted rain sensors can be used to disable
watering after summer rain.
• Solenoid valves should be above ground, grouped
together where possible and covered by a valve box.
13

18. Pressure
Irrigation components are designed to operate within a
set pressure range.Too much pressure causes misting
and high evaporative loss.Too little pressure causes
uneven application. If in doubt consult an irrigation
specialist who can conduct pressure and flow testing.
How much water to apply
The feeder roots of plants grow in the top 15 to 20cm
of soil.That’s why soil improvement is confined to that
depth and it also determines how much water needs to
be applied.
In improved sandy soils of the metropolitan area a depth
of 10mm of water, applied to the surface, is sufficient to
wet down to 15 to 20cm.The remainder of the volume
is taken up by soil particles.This 10mm application is
referred to as the Standard Drink.
Applying more than 10mm results in water seeping
down past the feeder root zone and being wasted.
Applying less than 10mm will prevent full development
of the feeder root system.The Standard Drink does vary
according to location and soil type. Further information
on this is available from the Water Corporation website
at www.watercorporation.com.au/savewater.
Every irrigation system has a different output so the only
way to determine how long to leave the system on for is
to measure how long it takes to deliver 10mm.This can
be done precisely using Waterwise Catchcups or
14

19. reasonably accurately using containers such as ice
cream cartons.
Making the most of Watering Zones
By grouping plants together on the basis of similar water
needs into areas called Watering Zones, you can ensure
that each plant in the zone gets as much water as it
needs and that no plant is overwatered.The result is
good healthy growth using less water.
Each zone must be capable of being watered
independently from other zones with different values.
This means separate lines controlled either manually by
separate taps or automatically by separate stations
operated from a controller.
Each plant whether in a 1, 2 or 3 Drop Zone gets the
same amount of water each time the system is turned
on (a Standard Drink) but what varies is the interval
between waterings.
The following guide to watering in the heat of summer
can be used as a starting point.Try extending the
duration between waterings as far as possible.
One Drop Zone A Standard Drink every 7 to 14
days or longer
Two Drop Zone A Standard Drink every 3 to 7 days
Three Drop Zone A Standard Drink every 1 to 2 days
Remember. Whenever any plant is watered is should be
given the Standard Drink, whether it be a bedding plant,
fruit tree or lawn.
15

20. Watering lawns
Warm season grasses have been proven to be both
water efficient and drought tolerant.They fit into the
‘Two Drop Zone’ of the garden.The unique aspect of
watering turf is the need to ensure an even application
over the whole area.To achieve this sprinklers should be
placed so that the spray from one sprinkler touches the
next sprinkler and rows of sprinklers should be
staggered. Use good quality part circle sprinklers on the
edges to prevent water being thrown onto hard surfaces
such as driveways or paving.
Never mix different types of emitters on the same line.
Solenoid valves should be covered by a valve box, not
buried beneath the soil.
Water early in the morning (5am to 8am). Never water
during the heat of the day.
Check your system regularly and replace worn nozzles
or broken seals as necessary.
Operation
Set your controller to deliver the 10mm Standard Drink
per application then follow the guidelines below changing
your lawn watering schedule as indicated.
The following watering frequencies are for ideal
conditions when there is sufficient water available.
When water is short the warm season grasses will easily
cope with watering only twice a week. And watering
with a hand-held hose can supplement watering by
16

21. sprinklers. Even at this frequency there is no advantage
in delivering more than the ‘Standard Drink’.
Month Frequency
January Every second day
February Every second day
March Every third day
April Every fifth day
May No watering
June No watering
July No watering
August Once a fortnight (if needed)
September Once a week (if needed)
October Every fourth day
November Every third day
December Every second day
Waterwise lawn management
Lawns can build up a spongy layer of brown material
between the soil and the green leaf.This is known as
thatch, which makes penetration of water difficult and
can lead to fungal diseases.
Thatch should be removed by a hard mowing in spring
or by vertimowing. Most hire shops have vertimowing
machines or advice can be obtained from the Lawn
Mowing Contractors Association.
Non-wettable soils should be treated with a soil wetting
agent in spring.This eliminates dry patches by allowing
water to penetrate.
17

22. Water early in the morning because in the heat of the
day up to 50% of water can be lost to evaporation and
wind drift. In addition, water applied in the evening may
lead to fungal problems.
Moss growing in a lawn may indicate excess water
application, poor drainage or insufficient sunlight.
A standard drink of 10mm is recommended, any more
is wasted.
Watering shrubs and perennials
Shrubs and perennials should be planted in Watering
Zones.
Micro-irrigation is ideal for these plants. If you have
improved soil that is well mulched even the thirstiest
of plants (Three Drop) can be maintained on a watering
schedule of every second day in the heat of summer.
This can be extended to every third or fourth day as
the weather cools down.
Very tough, water efficient plants may only need a drink
every month or so during their first summer after which
the micro-irrigation system can be disconnected and
re-cycled elsewhere in the garden.
Only the soil around the plant root zone needs to be
watered, not the area between plants.This minimises
nitrogen draw-down problems, weed germination and
also the number of slaters.
Adjustable emitters can be used to deliver variable
quantities of water to precisely the right locations.
18

23. Emitters should be exposed to allow for inspection.
Even when the water is being delivered precisely to the
plants at ground level, it is still desirable to water early in
the morning to minimise evaporation losses.
Your irrigation supplier can give you more details on
designing a micro-irrigation system for shrubs and other
parts of your garden.
Watering fruit trees
If the soil has been improved and a good mulch is
present, all fruit trees in the home garden, even tropical
species like mangoes, avocadoes and custard apples can
be kept growing healthily and productively by watering
only on alternate days during the heat of summer.
Where applicable, once the crop has been harvested,
the water may be cut back even further.
Flat throw, low pressure micro-irrigation sprinklers are
the most efficient means of watering fruit trees.They can
be set close to the ground and easily adjusted to wet
the entire drip zone area without being affected by wind.
A simple technique to ensure the most efficient use
of water is to shape the mulch like a saucer with the
highest par t immediately below or just outside the
drip line. Place the sprinkler in the middle and adjust
the height until it just throws out to the rim of the
saucer. The water is then caught and directed down
to the roots.
19

24. Drippers are generally not satisfactory for fruit trees in
sandy soils.They only wet a limited surface area and lead
to wastage as most of the water is lost to the deeper
soil. Drippers are slightly better in heavier soil where
they have a flatter wetting pattern but even then they
are not as efficient as micro-sprinklers.
Overhead watering of fruit trees is extremely wasteful
due to high evaporation losses. It is not recommended
in the home garden.
Watering pot plants
Micro-irrigation systems can be installed to deliver water
to individual pots around the verandah or patio.
Adjustable drippers allow for different pot and
plant sizes.
Terracotta is a porous material which allows moisture to
escape through the sides comparatively quickly. Before
planting up you should water proof the material by
either using a liquid sealant painted on to the inside of
the pot or lining the inside of the pot with polythene.
Make sure that a hole is cut in the polythene to coincide
with the drainage hole of the pot.
Self watering pots come in many styles.These pots are
very water-efficient as long as they are maintained
correctly.
Hydroponic systems are also water-efficient.Though they
may use a large liquid mass, the fluid is retained and
recycled in the hydroponic process with very little waste.
20

25. Slow release fertiliser release their nutrients gradually
over the growing season and are the ideal way to feed
pot plants.
Watering hanging baskets
Micro-irrigation systems can be adapted to deliver water
to individual hanging baskets. Adjustable multi outlet
emitters ensure a large area of the surface is moistened.
Protect hanging baskets from the drying winds.
Porous basket lines such as coconut fibre or wool should
be lined internally with polythene to reduce excess
moisture loss. Make sure that a hole is cut in the
polythene to allow for drainage.
Slow release fertilisers release their nutrients gradually
over the growing season and are the best way to feed
hanging baskets.
Watering bedding plants
Plan your flower beds to be mass displays. Do not place
a few plants here or there in odd spots all over the
garden but rather group your flowers together in a
suitable area which can be watered independently.
Many bedding plants have a high water demand and
may need hand watering on occasions.
Watering vegetables
These are generally high water demand plants which
need a sunny position. Because of their short life cycle
and varying size they are best watered with overhead
sprinklers.
21

26. Slowing down hot dry winds is very important. Creating
a windbreak on the exposed side will save a lot of water
and prevent damage to delicate plants.
Irrigation
There is more to saving water in the garden than
installing an efficient system to water a well designed and
carefully planted garden. Because the seasons change,
so too does the water demand of the plants. It is
necessary to adjust the watering programmes each
month to reflect these changes.
That’s why it’s important to make sure the controller is
easily accessible and that the instruction book is always
kept nearby. If you don’t have an instruction book you
can contact your local member of the Irrigation
Association for assistance.
After you plant
Lawn maintenance
Fertiliser use is closely related to water use. Over watering
or fertilising will result in the movement of nutrients past
the root zone, causing pollution of groundwater.
Never exceed the manufacturer’s recommendations,
apply frequent light applications of fertiliser to keep the
lawn healthy and improve its ability to survive on limited
water. Slow release lawn fertilisers are excellent.
They release nutrients over time, feeding the lawn each
time it is watered. Organic based fertilisers are beneficial
22

27. to the soil. Always water immediately after the
application of fertiliser.
Keep mower blades sharp. Dull blades damage the lawn
and increase moisture loss. Mowers should be set so that
only one third of the leaf is removed at one time.
This should leave a grass blade length of 10-15 mm.
This amount of leaf shades the root zone and reduces
evaporation.To reduce moisture loss, avoid mowing
during the heat of the day.
There is no benefit in top dressing lawns, this should only
be done to even out bumps and hollows.
Mulching gardens
Mulching can reduce evaporation loss from the soil
surface by as much as 70%. A mulch should be spread
over the entire planted area to a minimum thickness of
50mm. In addition to saving water mulching is beneficial
in many other ways.
Organic mulches are preferred because they:
• Break down over time and feed the plants.
• Improve the soil organic matter content as they
break down.
• Reduce evaporation loss from the surface.
• Encourage earthworms and soil microbial activity.
• Restrict weed growth and any weeds which do
germinate are easy to remove.
• Prevent wind and water erosion.
23

28. • Protect the roots from daily temperature fluctuations.
• Improve the appearance of the garden area.
Mulching material
The ideal mulching material is one which consists of
large, but irregularly shaped particles which do not hold
any water, allowing it all to run through to the soil below.
Raw materials like woodchips, chipped tree waste or
similar are the best mulching materials. Crushed brick,
stone or gravel may also be considered.
Soft mulches like lucerne hay, pea straw, seaweed and
compost are most beneficial in areas such as the vegie
patch or underneath fruit trees.
Lawn clippings and sheep manure do not make good
mulch, they are best composted.
Old newspapers can be used under a mulch for weed
control. However, thick overlapping layers of newspapers
may also prevent water penetration.
Applying mulches
• For general garden use mulches should be spread at
50-75mm thick.
• Always leave a breathing space of 50mm around
stems and trunks of plants.
• Organic mulches enriched with animal manures are
enormously beneficial when applied thickly (to 30cm)
around the drip zone of fruit trees.They should be
topped up as necessary during spring, summer and
24

29. autumn to maintain a minimum thickness (after
settling) of 15cm.
• Vegetable gardens should be mulched with ‘softer’
mulches such as compost, pea, hay or lucerne straw
or seaweed.
• In garden areas mulches should be topped up as
necessary; perhaps twice a year in both autumn
and spring.
• Mulches should never be raked up, turned over, dug in
or disturbed in any way.To do so will damage the fine
feeder roots which plants develop in the zone
between the mulch and the soil.
Changing an established garden
If your garden has grown over the years with plants
scattered all over the place, you can change it around.
Most high water use plants have shallow root systems
and so can be easily transplanted in winter or spring into
their respective groups in a new site.
Hardy, low water and drought tolerant species cannot
normally be moved because of their very deep root
systems.
The type, area and location of lawn in the garden can be
reconsidered. Excess areas of grass can be converted to
lower water use areas by:
25

30. • Using a herbicide containing the active ingredient
glyphosate. Apply the chemical according to
instructions using a garden hose as a marker guide
to ensure you get a complete coverage the first time.
Feed and water the lawn to get it growing vigorously
before applying the chemical. A second application
may be necessary for couch and kikuyu lawns because
of their strong root systems.
After 3 to 6 weeks all the grass will be dead.
Dead material can be left in place as a mulch while the
new plants are established.
Replacing a lawn area by planting it with a range of low
native groundcovers will ensure an ever changing scene
that is attractive to birds and gardeners alike with far less
maintenance than a lawn.Your local member of the
Nursery and Garden Industry Association can help you
with plant selection.
26

31. How Waterwise is your garden?
Take this simple test to find out.
Do you water twice a week?
Do you regularly use a soil wetting agent?
Do you improve the soil before you plant?
Do you water early in the morning?
Do you know how much water your plants need?
Do you know how much water you are putting on?
Do you change your watering schedule according to
the time of year?
Do you regularly check your irrigation system?
Do you mulch your garden beds?
Do you really need all the lawn you have?
27

32. Remember, the Water Corporation has lots
of ways you can save water both in the
house and garden.
Simply call the Waterwise Helpline on 13 10 39
or visit www.watercorporation.com.au
www.watercorporation.com.au
ISBN: 174 043 111 1