GARDEN DESIGN AND PLANT SELECTION
The type, quantity and condition of fuel has a very important effect on bushfire behaviour. The survivability of buildings, and of those who occupy and shelter in them, can be significantly enhanced or endangered by the type of plants around the building.
Landscaping for Bushfire has been developed by CFA in response to Recommendation 44 from the Victorian Bushfires Royal Commission. It forms just one part of our approach to help Victorian communities prepare for the fire season.
Residents in high bushfire risk areas need to be aware of their environment and the risks they face during the fire season. Planning ahead is essential for surviving the coming fire season. The most effective way to reduce risk in the garden is to focus on the location and arrangement of fuel on your property.
Even though all plants burn, measures can be taken to reduce fire intensity from garden plants. This guide identifies what you can do within defendable space to minimise the risk of losing your house or threatening the lives of occupants in a bushfire.
Landscaping for Bushfire is a valuable resource for home gardeners, landscape architects and nursery staff as well as CFA Fire Safety Officers, Vegetation Management Officers and Home Bushfire Advice Service consultants.
Landscaping for Bushfire bridges the gap between vegetation management and the Bushfire Management Overlay (BMO), providing advice on how to plan and maintain a garden while meeting planning permit conditions within the BMO.
Euan Ferguson AFSM
The views and final content of this document remain the responsibility of CFA.
CFA makes this information available on the understanding that you take reasonable care when using it. If you have any uncertainty about the application of the information to your particular circumstance, you should obtain further professional advice.
CFA does not accept responsibility for how you apply or rely on the information in this publication.
Cover image: Brachyscome, photo courtesy of Owen Gooding.
Published November 2011
SECTION 1: ABOUT THIS PUBLICATION
What information is covered?
What is landscaping for bushfire?
Why is landscaping for bushfire important?
SECTION 2: BUSHFIRE BEHAVIOUR
How bushfire destroys houses
SECTION 3: PLANNING A GARDEN
SECTION 4: DESIGNING A GARDEN
Types of gardens
SECTION 5: CHOOSING SUITABLE PLANTS
Plant moisture content
SECTION 6: MAINTAINING THE GARDEN
SECTION 7: PLANT SELECTION KEY
SECTION 1: ABOUT THIS PUBLICATION
CFA has developed Landscaping for Bushfire: Garden Design and Plant Selection for new and established homes in high-risk areas. This includes properties in the Bushfire Management Overlay (see below). The focus is on residential gardens, but the design principles can be applied to larger developments and subdivisions.
WHAT INFORMATION IS COVERED?
This publication provides information on landscaping to minimise the effects of direct flame contact and radiant heat on a house during a bushfire.
Sections 2-5 are a guide to the planning and design process. There are four example gardens with landscape plans, design notes and suitable plant options. These gardens illustrate the design principles of landscaping for bushfire for gardens in coastal, hilly, rural and suburban environments.
Section 6 draws attention to the importance of garden maintenance.
Section 7 includes a Plant Selection Key. This tool can be used to help choose suitable plants with low flammability. The key is also available as an online tool at cfa.vic.gov.au/plants
Section 8 provides information on further resources and references.
WHAT IS LANDSCAPING FOR BUSHFIRE?
Landscaping for bushfire involves planning, designing, planting and managing the area around a house.
The aim is to keep the area around a house and other structures (such as carports and sheds) free of plants that can easily catch fire and then ignite the buildings.
Landscaping for bushfire can be used to create new – or modify existing – gardens. It takes into account a number of factors that include:
understanding how fire behaves
creating defendable space
the location of plants within the garden
the flammability of individual plants
the need for ongoing maintenance.
The Bushfire Management Overlay is a planning control that applies to high bushfire risk areas in Victoria. It identifies areas where the bushfire hazard requires specified bushfire protection measures to be implemented.
The Bushfire Management Overlay is identified by planning schemes and can be found at Clause 44.06. It sets out:
the types of development that require a planning permit
the information that must be submitted with a planning permit application
the objectives, standards, mandatory standards and decision guidelines that must be considered in a planning permit application.
Visit dpcd.vic.gov.au for further details.
WHY IS LANDSCAPING FOR BUSHFIRE IMPORTANT?
Victoria is one of the most bushfire-prone areas in the world. The combination of vegetation, climate and topography creates ideal conditions for bushfire. Population growth in high-risk locations means that these communities need to be well prepared for bushfires.
Landscaping using appropriate design principles and plant selection can increase the likelihood of a house surviving a bushfire – even if the plan is to leave early.
Poorly located vegetation that burns readily may expose a house to increased levels of radiant heat and flame contact.
Well-placed vegetation with low flammability may actually help protect houses by:
reducing the amount of radiant heat received by a house
reducing the chance of direct flame contact on a house
reducing wind speed around a house
deflecting and filtering embers
reducing flammable landscaping materials within the defendable space.
A holistic approach is the best way to ensure proper preparation. It involves a combination of bushfire protection measures. These include:
house construction and maintenance
preparing a Bushfire Survival Plan (see the FireReady Kit – available at cfa.vic.gov.au)
having an adequate water supply and road access
garden design and plant selection.
FIRE RESISTANT, FIRE RETARDANT OR FIREWISE?
These terms are often used when talking about flammability characteristics of a plant. They have very specific and quite different meanings and should not be confused.
Fire resistant is a term that describes plant species that survive being burnt and will regrow after a bushfire. They are resistant to being killed by a bushfire, but not to being burnt. Therefore, they may be highly flammable and inappropriate for a garden in a high bushfire risk area.
Fire retardant can also be misleading when referring to plants. It implies that a plant will not burn readily or may slow the passage of a fire. It cannot be emphasised enough that all plants will burn under the right conditions.
Firewise, in this document, refers to the flammability ranking system applied to a plant by the Plant Selection Key (see Section 7). The term is linked with advice about maintenance and where that plant should be located within a garden.
While a well-planned garden is important, it is only one aspect of preparing for bushfire. It should not be relied upon in isolation. In high-risk areas on Severe, Extreme and Code Red days, leaving early is always the safest option.