Landscaping and garden design
- Landscaping and garden design can improve your home’s amenity, thermal performance, and value, and can reduce your environmental footprint.
- Sustainable landscaping aims to work with the natural landscape and cycles. If the site still has vegetation, keep as much growth as possible, especially trees which will take a long time to be replaced.
- Minimising hard surfaces will reduce stormwater runoff from your site, and using mulch will reduce your garden’s water requirements.
- Using native and indigenous plants in your garden will provide habitat for local species. Native and indigenous plants also usually have lower water requirements than exotics, thus reducing your water use.
- In bushfire-prone areas, you can reduce the fire risk for your home by choosing less flammable plants and landscaping elements, including gaps in plantings, and avoiding plants near windows.
- Growing vegetables, herbs and fruit can reduce your environmental impact by reducing your reliance on food bought elsewhere, with associated use of water, energy and transport.
Understanding landscaping and garden design
Landscaping and garden design can simultaneously address aesthetics and amenity, water management, air quality, climate modification, biodiversity, habitat creation, and local food production — and can help to warm and cool your house. The planning and design of outdoor space should be considered an integral part of your home’s sustainable design.
Sustainable landscaping is an approach to designing and constructing the artificial landscapes that surround our buildings, and improving the natural landscapes that already exist. Ideally, these landscapes should maintain themselves and survive by being part of the natural cycles of the local environment.
The scope of design of outdoor space may range from revegetation of a large bush block to the detailed design of small courtyard spaces. Sustainable landscaping means putting back much of what may have been in place before development. It may also mean introducing things that were not there before, to ensure that the landscape can be socially, economically, and environmentally sustainable in future.
Benefits of sustainable landscaping and garden design include:
- increased biodiversity – native and indigenous vegetation can support and increase local biodiversity by providing habitat, especially for birds, insects and lizards
- improved air quality – vegetation can remove pollutants from the air and create buffers and filters for wind and dust control
- reduced energy use – as an integral part of passive design strategies, vegetation can provide cooling through shading and evapotranspiration. Shading to the north of a home should be provided by deciduous plants which lose their leaves in winter. Australia has few deciduous native trees (for example, Toona australis – red cedar) so exotics may be required
- water management – good landscaping can reduce the impact of stormwater on the site and reduce the need for watering plants. It can even be part of a wastewater treatment system
- food production – growing your own fruit and vegetables can help to reduce your ecological footprint
- psychological wellbeing – a new science of ‘biophilia’ (love of nature) is developing from the recognition that vegetation and natural environments have a measurable impact on our psychological health.
Photo: Edwina Robinson
Designing a sustainable landscape and garden
Sustainable landscaping is about more than planting Australian native vegetation. It is about designing landscapes to fit the new site ecology created when buildings are constructed. Sustainable landscaping includes such diverse approaches as restoring creeks where development has changed or removed their previous course, and creating roof gardens to replace the productive capacity of the land taken up by a new building.
Design landscaping to be experienced from both inside and outside the home. Sustainable landscaping can be employed to create shade, or to enhance or frame views. It can be attractive to look at, and can also provide privacy from surrounding buildings. It can supply food, and help create pleasant areas for recreation.
The location of vegetation can influence choices about building orientation: a tree may shade part of a site and limit solar access but be an essential part of retaining soil, providing habitat and creating shelter. When choosing a site, take account of existing vegetation for windbreaks, shading and views, and remember that trees and vegetation can form part of the view, not just block other views.
Sustainable landscaping may be used to control the amount of salt in the soil (salinity), help increase the processing of carbon dioxide through photosynthesis and absorption of carbon, and contribute to restoring and maintaining biodiversity.
In recent years, the definition of a sustainable landscape has evolved to include landscape elements that are literally part of a building. Green roofs and walls can be constructed specifically to support native vegetation as part of a wider strategy for enhancing or restoring the natural biodiversity and reducing urban heat island effects.
Source: Paul Downton
Landscape materials account for much of the embodied energy in a landscape project. Consider reusing existing site materials such as pavers and excavated rocks. Wherever possible, use recycled materials such as crushed brick or concrete, or recycled timber. If recycled timber is unavailable, use sustainably managed plantation timber or timber composite products in preference to imported rainforest timbers. Avoid excessive amounts of paving which can contribute to microclimate heating and reduced site permeability – pave only where you sit, stand, and walk.
Gardens require water, but smart choices can reduce the amount of mains water you need to use. Low-water-use vegetation can greatly reduce the need for supplementary garden watering. Indigenous species are usually the best for the low rainfall conditions found in much of Australia.
You can use your roof to capture rainwater that that can then be used to irrigate vegetation. Capturing water this way also reduces the release of stormwater to the street. You can also recycle wastewater from your home to water plants.
The use of waterbodies like ponds and water features can be integrated into a sustainable landscape solution as part of an overall water management system and the passive climate response strategy for your home.
Sustainable landscapes use plants that perform well in the local area. Suitable plants may include native and indigenous plants, as well as exotics (non-Australian plants) from similar climatic zones. Plants should ideally perform well once established on existing soils and with existing rainfall patterns without the need for excessive watering, soil modification, or intensive maintenance regimes.
What is the difference between ‘native’ and ‘indigenous’ plants? Native plants are all plants from Australia; indigenous plants are those specific to a particular place. Avoid plants that are considered invasive or unwanted species in your region. Nurseries may still sell them, so check with a reliable source, such as your regional natural resource or catchment board.
A sustainable garden uses a wide range of plants from different structural categories, such as trees, screening shrubs, medium shrubs, low shrubs, groundcovers, strappy plants and grasses, climbers, perennials, and bulbs. This kind of ‘structural’ diversity encourages wildlife into the landscape.
Photo: Ben Wrigley (© Light House Architecture and Science)
Lawns are common features in Australian landscapes, but they generally require high levels of water, fertilisers, and energy to maintain their appearance. These impacts can be minimised by:
- selecting a turf that requires less water and fertiliser
- replacing exotic grass species with drought-tolerant low-maintenance native grasses that retain the appearance of a conventional lawn
- reducing the extent of lawn and increasing the area of hardy garden beds
- removing lawn and replacing it with a mix of groundcovers and non-woody plants and permeable surfaces such as gravel.
Synthetic grass products are an inappropriate choice for sustainable landscapes. Nonliving, synthetic plant substitutes diminish, rather than add to biodiversity. They are products of mining fossil fuels and a great deal of water and energy are used in their manufacture. They also do not deliver the urban cooling benefit that planting does. See outdoor water use for more information on lawns.
The traditional Australian quarter-acre block was regarded as a place to grow food for the family. Even a small block can support some food production. Growing fruit and vegetables is a way of reducing our ecological footprint. If food is grown locally and sustainably, it reduces reliance on the use of water, energy and multiple forms of transport to obtain it from elsewhere.
Most vegetables and fruits require fertile soils with good drainage, regular watering, and moderate amounts of sunlight depending upon the climate. Vegetable gardens can usually be made in raised garden beds with the addition of home-made compost and well-rotted animal manures. Fruit and vegetables generally require regular drip irrigation.
Photo: Paul Downton
Keeping bees or chickens in your backyard can provide benefits but check with your local government for regulations and requirements before you purchase them. Roosters, for example, are not needed to produce eggs and are generally not allowed to be kept on residential premises.
Photo: Getty Images
Biological diversity and habitat restoration
Sustainable landscaping can assist in protecting and restoring biodiversity – which is the variety of plants, animals and microorganisms, the genes they contain, and the ecosystems of which they are part.
Residential development, especially in growth corridors, city fringes and holiday towns, often clears native vegetation. Even the most sensitive development can affect the integrity of natural ecosystems:
- Habitat is degraded when pest animals and plants are introduced — cats can decimate native bird populations and weeds can encroach on remnant bushland.
- Buildings and roads alter drainage patterns and soil structure.
- Stormwater runoff and septic tanks alter nutrient levels in waterways and can cause other long-term problems, such as toxic algal blooms that can kill fish and cause illness in people.
- Bushfire requirements affect landscape design, such as maintaining minimum distances between houses and trees and having minimal vegetation in areas adjacent to houses.
- Once land is cleared, it is almost impossible to recover the full suite of indigenous species, remove introduced species and restore ecological processes, but sustainable landscape design can go a long way towards restoring biodiversity.
Particularly challenging are sites where there is little ecological value or where pre-existing ecology has been destroyed.
Objectives for biodiversity conservation include:
- retaining native vegetation and increasing its quality and area wherever possible
- recovering threatened communities and species
- preventing rare species from becoming threatened
- repairing ecological processes.
Photo: Maeli Cooper
Design for biodiversity benefit
Sustainable landscaping should try to incorporate biodiversity objectives into the design approach from the outset. You may find innovative ways to make a positive contribution:
- Design to minimise the use of water, land, non-recycled materials, toxic chemicals, and energy.
- Identify flora and fauna, potential threats, and ways of avoiding or minimising impacts as early as possible in the project. In situations where significant impacts are likely, a flora and fauna survey may be necessary and a nature conservation consultant may be helpful.
- Find out if aspects of Australian or state and territory legislation apply and if the planning scheme has policies that affect your site. There may also be biodiversity plans at the state, bioregional, or catchment level. The planning department of your local government, or your regional natural resource or catchment board, should be able to advise you.
If you do not have a large garden space or want to contribute to landscape restoration in other ways, consider participating in native landscape and ecosystem restoration projects. These projects are often run by not-for-profit organisations such as Greening Australia, Trees For Life in South Australia and Trillion Trees in Western Australia. Many tree planting and revegetation programs are also intended to compensate for carbon emissions.
Minimise damage on site
Building a house often has a substantial negative impact on its site. By taking care of how the site is developed, and using sustainable landscaping practices, the amount of damage can be greatly reduced:
- Retain as much native vegetation as possible as uncleared areas are a resource to be conserved.
- Avoid unnecessary disturbance to vegetation and soil, and limit clearing outside your building footprint.
- Retain significant habitat trees including dead trees with hollow limbs or trunks that provide shelter and breeding sites for animals.
- Consider your impact on waterways. Ensure that silt, lime, cement, paint, and chemicals do not wash into drains or nearby watercourses. Refer to Sediment control for more information.
Design for habitat
A garden using native and indigenous plants requires much less watering and links your home to the ecosystem in which you live. Many animals, including birds, invertebrates and small lizards, may be able to use your garden for habitat resources:
- Rehabilitate disturbed areas with saved topsoil and salvaged plants.
- Use native and indigenous species in the garden.
- Avoid environmental weeds which may spread into native vegetation and contribute to the decline of biodiversity.
- Maintain links between any adjacent bush and your garden.
Your garden can be particularly useful for local bird species. Bird life is an important part of every ecosystem and it can easily be encouraged around your home.
- Create native bird habitats as part of your home’s landscaping by ‘birdscaping’ with indigenous plants around buildings to provide food and shelter.
- Use prickly plants; these form an excellent barrier and provide shelter for small birds.
- Design windows with tinted glass and screens so they are visible to birds.
- Consider using wall and roof gardens that grow indigenous plants.
- Create ponds with edible fish and plants.
- Provide nesting boxes.
- Ensure wildlife is not compromised or threatened by domestic pets. Native animals can be protected from cats by keeping the cats indoors or in purpose-built enclosures.
Photo: Edwina Robinson
Design for climate change
Climate change will affect plants and local species, and your home’s thermal performance and energy needs. Consider the predicted changes for your region and adapt your landscape accordingly. To cope with increased temperatures, shade the walls of your homes using trees, large shrubs and climbing plants. Where space is limited, use shade structures with climbers to reduce outdoor and building temperatures. Ensure the landscape has sufficient permeable surfaces to cope with increased rainfall events and return rainwater to the soil and subsoil layers. Capturing water in rainwater tanks and through greywater recycling will ensure water is available to sustain plants during drought periods.
In dry regions, consider creating a small mini-oasis which can provide passive cooling to the house. Locate this area on the cooler side of the building that receives evening breezes. Incorporate moisture-loving plants, a water feature, permeable paving and water-harvesting methods in this space.
Design for bushfire-prone areas
Increased bushfire risk will be a feature of climate change in many areas of Australia. The siting, selection and maintenance of your garden and landscaping can affect how vulnerable your home is to bushfire. Typically, landscaping is not used to determine the bushfire attack level (BAL) rating of a building. Poor choice and placement of plantings and other landscaping features may compromise what is otherwise a good bushfire design and well-constructed building.
Consider plant selection and ongoing maintenance. This includes selecting or retaining lower flammability plants. Look for plants that have:
- high leaf moisture content
- larger leaves (for example, avoid fine-leaved species such as she oaks)
- denser foliage
- smooth bark
- lower oil content in leaves (for example, avoid olives)
- high mineral or salt content (for example, salt bushes)
- low levels of litter or dead debris.
Dead materials from plants can accumulate on roofs, guttering, and windowsills and be ignited by embers. Also, be careful of plants that hold large amounts of dead material within the core of the plant while exhibiting a green outer foliage, such as ornamental cypress pines – such plants can have a higher risk of ignition.
Plants should be easy to trim and maintain. Ensure you raise the ‘skirts’ of trees by trimming lower limbs up to 2m off the ground. This helps to prevent fire from getting into the canopy from the ground.
When planting, ensure you have:
- gaps in vegetation to reduce the progress of fires
- no plants near windows, where burning plants can crack and break glazing
- no trees within 10m of the house
- no shrubs and trees in the area you plan to use as an escape path from the fire, including at doorways
- few shrubs under trees.
Landscaping should not encourage the spread of invasive weed species (for example, lantana). All plants can burn, so managing weed species will lower overall fuel loads.
Source: Country Fire Authority Victoria
Other landscaping features
Flammable mulches can ignite and generate embers, so it is a good idea to use gravels rather than bark mulches for garden beds and pathways.
Other potentially flammable landscaping features include fencing (metal is best), cubby houses, sheds, and outdoor furniture. Placing these features away from the main building will help to reduce radiant heat and flame contact with the main building and also provide a defendable space for fire-fighting crews. Anything in close proximity to the house should be either non-combustible or easy to move inside away from exposure to flames embers or radiant heat.
References and additional reading
- ABC, Gardening Australia.
- Australian National Botanic Gardens, Environmental weeds in Australia.
- Byrne J (2006). The green gardener: sustainable gardening in your own backyard. Viking Press, Camberwell, Victoria.
- Chadwick D (2005). Australian native gardening made easy: a comprehensive, no-nonsense guide to creating and caring for your garden, 3rd edn, Little Hills Press, Mount Druitt, New South Wales.
- Country Fire Association, Victoria, Plant selection key.
- Country Fire Association, Victoria, Landscaping for bushfire.
- Greening Australia.
- Mollison B (1988). Permaculture: a designer’s manual, Tagari Publications, Tyalgum, New South Wales.
- Mollison B (1994). Introduction to permaculture, 2nd edn, Tagari Publications, Tyalgum, New South Wales.
- Ramsay C and Rudolph L (2003). Landscape and building design for bushfire areas. CSIRO Publishing, Canberra.
- Sullivan C (2002). Garden and climate, McGraw-Hill, New York.
- Sustainable Gardening Australia.
- Tasmania Fire Service, Fire retardant garden plants [PDF].
- Thompson J and Sorvig, K (2008). Sustainable landscape construction: a guide to green building outdoors, 2nd edn, Island Press, Washington DC.
- Thompson P (2002). Australian planting design, Lothian Books, Port Melbourne, Victoria.
- Wolverton B (1996). Ecofriendly house plants: 50 indoor plants that purify the air in homes and offices, Weidenfeld and Nicolson, London.
- Visit Designing a home for more information on what to think about when designing an energy and water-efficient home
- Review Outdoor water use for more ways to save water in your garden
- Explore Streetscape for ideas on what to look for and promote around your home
Original authors: Paul Downton and Kathy Preece
Contributing author: Edwina Robinson
Updated: Paul Downton, 2013 and Dr Grahame Douglas, 2020