Guide 4
Landscaping: An Integral Aspect
of Sustainability
Landscaping should form an integral part of the sustainable house. It is one of the key elements that contribute
to the overall liveability of a home.
Go beyond having a garden that is purely ornamental and use landscaping elements that enhance a home’s
climatic performance.
Introduction
In the past, the Townsville garden has been a water-
hungry lawn, running from the front yard to the back fence
and passing a mango tree on the way. It often had some
shrubs and the occasional weed-ridden planter bed.
A well-designed, Townsville garden should be integrated
with the design of the home to maximise its overall
sustainability by:
1. Creating optimal shade to the house and garden
areas; and
2. Promoting prevailing breezes through the property.
The following information demonstrates appropriate
shading solutions according to orientation on a property.
North-Facing Aspect
On a north-facing area (Figure 2) the sun will be high in the
sky and often overhead. Landscaping that best provides
shade from directly above will be high and horizontal in
form and shape.
Figure 2 Landscaping on a north-facing area.
Trees with a high horizontal canopy and exposed trunk
are most effective in this situation (Figure 3).
Figure 3 Shape and form of canopy planting
for north-facing areas.
Pergolas (Figure 4) are also an effective landscaping
device to use on north-facing areas. They may be covered
with hard materials such as corrugated iron or plants
such as climbers.
Figure 1
The sun’s daily movement through the sky.
Further information relevant to the sun’s
movement can be found in Guide 1 –
Orientation for Townsville Homes.
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1. Landscaping for Shade
Landscaping should be used to provide shade to the
garden areas and to as many of the external walls and as
much of the roof of a home as possible.
Providing shade reduces the amount of heat absorbed
by the home. Hence, protection in the form of shade is
essential and will greatly improve the climate inside the
house. This sounds obvious but, in Townsville, using
landscaping to shade the home is an uncommon practice.
The way the sun tracks through the sky in Townsville
(Figure 1) determines where certain plantings should be
located and how they should perform.
Figure 4 North orientated pergola.
FACT 1
Landscaping correctly can create a micro-climate
close to the home. This is because plants affect the
air temperature and moisture content (humidity) as
well as provide shade.
Plants give cooler shade than man-made
structures. This is because of the transpiration and
evaporation of water from the plant’s leaves.
The shade associated with transpiration created
by vegetation can lower the temperature by an
estimated 3°C to 5°C.
High canopy trees in combination with low shrubs
or groundcovers (Figure 5) are a good landscaping
combination for north-facing areas. They also cool
prevailing breezes, see Section 2 - Landscaping for
Breezes in the latter part of this guide.
Figure 5
Ideal plant selection for north orientation;
high canopy trees and low groundcovers.
West and East-Facing Aspects
On west and east-facing areas (Figure 6), the sun will be
low in the sky, penetrating deep into the garden and onto
the unprotected walls and windows of the house.
Landscaping that will offer best protection will be vertical
and dense in form and shape (Figure 7).
Figure 7
Typical shape and form of planting
to west and east-facing areas.
Mixed-height planting, composed of tall-growing shrubs
together with trees or multi-stemmed palms, are also
useful for shading west and east-facing areas (Figure 8).
If space is limited, vertical structures, such as; a trellis
or lattice screen covered with climbers (Figure 9), can be
just as effective.
Figure 8 Mixed-height planting will shade east
and west orientations.
When planting trees and shrubs for shade be careful
not to block prevailing breezes. This will be discussed in
Section 2 - Landscaping for Breezes in the latter part of
this guide.
South-Facing Aspect
The southern areas on a property have little influence
on the climatic performance of a house. In Townsville,
the sun is in the southern sky from approximately mid
November to mid January. However, its effect is minimal
and can be controlled with simple roof overhangs on the
southern side of the house and vertical landscaping to
the west and east as mentioned above.
Figure 9 Vertical trellis or lattice screen.
Which Plants to Use for Shading?
Refer to the Plant List Appendix at the end of this guide
for appropriate plant selection according to north, west
and east orientations.
Further Shading Tips
A. Shade large paved areas such as the driveway and
parking areas to reduce radiating heat and glare. Shade
trees, sails and pergolas covered with climbers are good
solutions.
B. Combining natural and man-made shade can create
some of the best results. For example; install a man-
made lattice on west and east areas whilst planting trees
on north areas to shade the roof.
C. A tree may take up to five years to reach the height
needed to provide the required shade. You may want to
install a sail or similar structure to provide instant shade
whilst landscaping becomes established (Figure 10).
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Figure 6 Landscaping to west and east-facing areas.
Figure 10 Man-made shade such as a sail structure
provides instant shade while trees grow.
2. Landscaping for Breezes
Landscaping can assist in cooling and directing breezes
to indoor and outdoor living areas. However, incorrect
planting can block breezes from reaching the house.
FACT 3
The dominant wind direction in Townsville is from
the north-east. This is referred to as the prevailing
breeze.
Plant sparsely, or select species that allow breezes to
filter through on the property’s north-east areas, where
prevailing breezes come from (Figure 11). For example,
high canopy trees in combination with low shrubs and
groundcovers are a great combination for this aspect as
prevailing breezes will filter through the vegetation and
be cooled prior to reaching the house.
Use Water Features
Position swimming pools and water-features to your
advantage. In other words, to the north or north-east
(upwind) of your home (Figure 12) and shade where
possible.
Breezes increase the rate of evaporation over a body
of water. This may result in the air temperature being
cooled. A ‘cooled’ breeze will contribute to a cooler home
environment.
Figure 12 North to north-east. Ideal location of
swimming pool or water body.
In the same way that well-designed landscape elements
can cool and direct breezes into the home, badly
designed landscape elements can heat or block breezes.
The following are examples of poor landscaping choices
that should be avoided when possible.
The incorrect location of driveways and uncovered car
parks (Figure 13) constructed from materials such as
concrete, bitumen and pavers will alter the quality of
the breeze as it enters the house. A breeze moving over
‘hard’ surfaces will heat up.
Reducing the amount of hard surfaces that radiate heat
around the home can be as simple as choosing tracks
for your driveway instead of full solid concrete. Consider
alternative materials and methods before you make your
choice.
Horizontal pergolas or vertical lattices are also quick and
effective shade solutions as climbing plants can cover
them within two years.
Figure 11 Canopy trees and low groundcovers create
the preferred landscaping for north-east
areas.
Figure 13 Unshaded ‘hard’ surface areas radiating heat.
Do Not Block Prevailing Breezes
Dense landscaping can shade and significantly cool the
house and garden, but avoid dense planting to the north
and north-east of the property (Figure 14) as it will block
and redirect breezes away from the house.
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FACT 2
Plan your garden carefully. For example, large
trees are a great choice; however, they may cause
damage if located too close to a slab home or
overhead powerlines. Check the predicted mature
plant size before you plant and locate them
accordingly.
Planning Services
Special Projects Unit
Ph: 4727 9000 Fax: 4727 9052
www.townsville.qld.gov.au
CONTACT
Figure 14 Avoid dense planting to the north and
north-east.
Avoid locating structures, such as garages, carports,
sheds and greenhouses (Figure 15) in the way of prevailing
breezes.
Figure 15 A structure redirecting prevailing breezes.
FACT 4
Neighbourhoods with street trees are cooler
because shade reduces radiating heat from hard
surfaces. Shading in combination with transpiration
contributes to lower surrounding temperatures.
If you would like to have trees planted on your
footpath you can apply to Council’s Parks
Department.
Scenario 2 - A horizontal
pergola and vertical lattice
provides extra shade to the
north. Screening and mixed
canopy planting to the east
and west.
Three Effective Landscaping Scenarios
Figure 16 - Scenario 1.
Figure 17 - Scenario 2.
Plant List Appendix (All Natives)
Shade Trees for North Orientation
Wide spreading canopy and exposed trunk.
Acacia auriculiformis - Black Wattle
Terminalia sericocarpa - Sovereign Wood
Terminalia muellerii - Mueller’s Damson
Ganophyllum falcatum - Scaly Ash
Syzygium tierneyanum - River Cherry
Cassia javanica - Pink Cassia
Trees and Shrubs for West and East Orientation
Trees and shrubs of vertical form to create mixed-height screen
planting.
Bursaria spinosa - Sweet Bursaria or Blackthorn
Premna serratifolia - Creek Premna
Brachychiton acerifolius - Flame Tree
Brachychiton populneus - Kurrajong
Grevillea baileyana - Findlay’s Silky Oak
Syzygium leuhmannii - Small-leaved Lillypilly
Syzygium fibrosum - Fibrous Satinash
Syzygium australe - Scrub Cherry
Phyllanthus cuscutiflorus - Cuscus
Polyalthia longifolia - Pendula
Eugenia reinwardtiana - Cedar Bay Cherry
Climbers for Pergolas and Trellises
Pandorea jasminoides - including ‘Rosea’, ‘Lady Di’ and ‘Alba’-
Bower of Beauty
Pandorea pandorana - Wonga Vine
Ipomea horsfalliae- Cardinal Creeper
Trachelospermum jasminoides – Star Jasmin
Scenario 1 - Simple shade
solution with shade trees on
the north and mixed canopy
planting on east and west.
The north and north-east
orientations
are
more
sparsely planted to allow
prevailing breezes through.
Figure 18 - Scenario 3.
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Scenario 3 - Even in a narrow
side-boundary space, the
house can be effectively
shaded
from
the
hot
afternoon sun with a vertical
lattice. A pool to the north-
east cools prevailing breezes
entering the property.
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