When planning a rural garden, consider house and garden location, the placement of other structures, elements and services, and good planting design strategies.
Many rural gardens are on larger farming properties surrounded by pasture paddocks and grasses. These can dry rapidly over summer, causing fire to spread from the paddock to the garden.
Other rural gardens are located just outside cities and larger towns. They generally form part of a small ‘farmlet’, with larger productive and/or ornamental gardens.
One of the most effective ways to reduce fire risk in rural sites is to have a defendable space around the house.
Placing farm dams in the direction of the most likely path of a fire provides a fuel-free area and further separation between the bushfire hazard and the house. Dams also form a useful irrigation source for the garden. Keeping plants well hydrated will help reduce heat stress over summer when they often become more flammable.
Planting design solutions in the rural garden include the use of lawns, gravel surfaces and kitchen gardens.
These features ensure there are areas of low fuel directly around the house.
Careful placement of all vegetation in the garden is important. In particular, break up the continuity of fuel available to any fire and provide adequate separation between vegetation and the house. This includes locating trees at least 1.5 times their mature height from the house and locating other plants away from vulnerable areas (such as windows, decks and eaves).
The strategic placement of windbreak trees or hedges outside the defendable space of the house block can reduce wind speed and catch embers produced by the fire. Tree selection should consider low flammability characteristics and good maintenance practices need to be applied.
Effective ways to minimise the spread of fire within the garden is by using irrigated, well-spaced orchard trees and good separation of plantings throughout the garden. This can also be achieved with vertical and horizontal separation of garden plantings. In particular, separation between shrubs and trees will remove ladder fuels and break up direct fuel corridors to the house.
EXAMPLE: RURAL MODEL GARDEN
The garden and home paddock design aims to reduce spread of a grassfire to the house from surrounding paddocks and properties. It also aims to limit the spread of fire within the garden to the house.
In this garden example, the most likely direction of fire is from the north-west. However, fire can spread from any of the paddocks surrounding the house. Therefore, landscaping for bushfire design principles should be applied throughout.
The farm dam is placed in the most likely direction of the fire. The front lawn, tennis court, front driveway, turning circle, and kitchen garden all provide further separation and areas of low fuel between the fire hazard and the house.
A mass planting of irrigated ornamental orchard trees acts as a windbreak and helps provide protection from ember attack in the home paddock. Shrub masses between the house and these trees are ornamental and are kept away from the tree canopies to prevent them acting as ladder fuels. There is also good separation provided between the shrub beds to break up the spread of fire.
Planting has been kept away from the house with lawn and gravel paths. Planting near the driveway softens the view from the house with low succulent plants. These are also planted away from vulnerable areas of the house. Decks around the house are replaced with non-flammable materials, such as concrete and steel.
Densely planted windbreaks are provided on the southern and western boundaries outside the defendable space. While these are common features on rural properties, choosing low flammable species in this example reduces the fire risk.
The shed with chemical stores, clothes line and fire wood are all located well away from the house. Non-combustible water tanks (concrete or corrugated iron) are fed off the roof of the shed and may provide an additional water source during a fire. Grapes and berry plants are located at the rear of the property near the shed and are kept well watered over the summer months to reduce their flammability.
Plants chosen for the model garden have been selected for their firewise properties.
In the orchard, a mixed collection of small fruiting trees have irrigated lawn beneath.
They include Prunus avium (Sweet Cherry), Prunus salicina (Japanese Plums) and Prunusdomestica (European Plums). All are trained to an open form and maintained with their lower branches pruned to provide separation.
A small, decorative tree Arbutus x andrachnoides (Hybrid Strawberry Tree) is located in the lawn turning circle. With smooth bark, an open habit, attractive flowers and form, this display specimen is easily viewed from the house.
At the outer perimeter of the home paddock on two sides are windbreak plantings.
The species selected includes Acmena smithii (Lily Pilly) on the southern boundary and Casuarinacunnighamiana (River Oak) on the western boundary of the home paddock.
These trees have a moderately dense habit and retain little dead leaves or twigs. The grass beneath these trees is mowed low and is well watered during summer.
Around the perimeter of the lawn area are four rectangular clumps of herbaceous plants growing up to 1 metre in height.
These include Festuca glauca (Blue Fescue), Dianella caerulea (Paroo Lily), Lomandra longifolia (Spiny-headed Mat Rush), Phormium ‘Apple Green’ (New Zealand Flax), Salvia nemorosa (Woodland Sage) and Strelitzia reginae (Bird of Paradise).
All are drought-tolerant plants with strappy or vertical foliage and interesting flowers. They readily maintain a green and lush habit over summer.
PLANTING AT FRONT DOOR
Closer to the house, flanking the front door are beds of drought-tolerant succulent plants. These have been chosen for their colourful foliage, low-growing habit, fleshy leaves and ease of cultivation.
They include Aeonium arboretum (Tree Aeonium), Agave attenuata (Swans Neck Agave), Cotyledon orbiculata (Pigs Ears), Echeveria cvs. (Hens and Chickens), Tradescantia pallida (Purple Heart), Kleina mandraliscae (Blue Chalk Sticks), Sedum pachyphyllum (Jelly Beans) and Sedum (Matrona).
Two hedges are used in the garden. These were selected for their low flammability characteristics. In particular, the absence of oils, waxes and resins in the leaves and stems, and their low retention of dead foliage after pruning.
At the front of the house a low hedge (to 50 centimetres in height) of Buxus sempervirens ‘Suffruiticosa’ (Dutch Box) is planted either side of the pathway. This is a low-growing form of the Common Box with a medium texture and a moderately dense habit.
At the rear of the house a low hedge to 1 metre high is planted to frame the house garden. This hedge uses Escallonia (Pink Pixie). This is a low-growing hybrid form of this compact species that has fleshy leaves year-round. Like all hedging plants both these species require regular maintenance.
PERENNIAL DISPLAY PLANTING AT REAR OF HOUSE
Within the house garden towards the rear are mixed plantings. These contain drought-tolerant, flowering herbaceous perennials, which range from 30 centimetres to 1 metre in height. Plants include Achillea cultivars, Anthemis montana, Beschorneria yuccoides (Mexican Lily), Festucaglauca (Blue Fescue) ‘Purpe Emporer’, Dahlia ‘Licoco’, Euphorbia (Compton Ash), Penstemoncultivars, Salvia nemorosa, Sedum cultivars and Tulbaghia violacea (Society garlic). These will be irrigated to ensure a lush habit over summer, and mulched with pea gravel – a type of non-flammable mulch.
The lawn species is Pennisetum clandestinum (Kikuyu Grass). It is tough, hard wearing and able to be managed at a low height. These lawns will be irrigated over summer to assist in maintaining a green, defendable space.