The foothills and mountains of Victoria generally provide exceptional conditions for growing gardens. They typically have higher rainfall, cooler temperatures, deeper soils and well-drained sites. This environment enables a wide range of plants to be grown successfully.
As a result, hills gardens often display great diversity and layers of vegetation, from large trees and shrubs through to ground covers and herbaceous perennials.
The design of a hills garden should carefully consider the local site and context. Many gardens will be located in areas adjoining native forests or tall trees that are highly flammable. In these high-risk sites bushfire can move readily across the landscape (see Leaving Early text, above). Leaving early is the safest option.
Dual-access driveways and multiple entry points should be considered in the design of a garden. This will improve access into and from the site. Using stone or masonry retaining walls is preferable to timber structures. Terracing should be considered on very steep sites to support level areas.
Good garden maintenance is essential in a hills garden. These gardens can produce large amounts of plant growth, including litter, bark and dead leaves.
To reduce fuel load build-up, removal of litter through tree and shrub canopies, such as dry bark hanging from trees and on the ground, is an important garden maintenance task. Pruning trees to raise the canopy 2 metres from the ground and placing trees to ensure canopies are at least 2 metres apart reduces potential fire spread into and between the canopies.
The most suitable vegetation to plant around the house is irrigated, green lawns. Any trees should be placed at least 1.5 times their mature height from the house. Choose low flammable and lush vegetation, particularly in high-risk areas. Locate plants in clumps, away from the house and other flammable structures.
Remember fire can spread from any direction, regardless of slope and aspect.
This hills garden is located within steeply sloping, dense Eucalyptus regnans (Mountain Ash) forest. It is typical of many areas including the Dandenongs and the Macedon and Kinglake Ranges.
Some indigenous eucalypts have been retained within the property but only those that are located more than 10 metres from the house. They have been retained in clumps and do not overhang the house. Any hanging bark and litter from these trees will be removed from surrounding garden plants during the summer months to help prevent fire ladders into the high canopies.
The vegetation chosen beneath these trees includes herbaceous ground covers. They ensure maximum separation between vegetation and the canopy. These have been carefully chosen for their low flammability and dense, lush summer growth.
The orchard trees are planted with 2 metres between the mature canopies to reduce potential fire spread. The extensive lawn areas slope downwards to the house and those at the property’s southern end provide areas of low fuel within the defendable space. They will be irrigated and mown low over summer.
Stone terracing reduces the steepness of the slope and makes necessary maintenance easier. The house has been located along the eastern side of the property to provide maximum separation between the house and the main fire hazard to the west.
A vegetable garden and orchard sit in a series of terraces between the unmanaged vegetation and the house. They have been included in the defendable space because of their low flammability. They will be kept well-watered over summer using the adjacent steel water tanks.
The retaining walls on the slope 6 are all constructed of stone. Stone paving and a lawn area located between the house and potential fire hazard maximise separation opportunities. The eastern side of the house is maintained with gravel as a vehicle storage area and includes steel retaining walls.
The caravan in this space would be moved off the property during summer and the clothes line and wood shed have both been located well away from the house.
Plants chosen for the model garden have been selected for their firewise properties.
The small feature tree in the main lawn, Parrotia persica (Persian Ironwood), has been chosen for its attractive autumn foliage and summer shade. It also has a deciduous lifecycle, smooth bark, open, diffuse habit and low leaf-litter production over summer – all low flammability characteristics.
Herbaceous plants are used in the front garden to provide ground cover throughout the year and seasonal colour over winter, spring and summer. All are shade-tolerant perennials with a low-growing habit (to 30 centimetres in height) and have leaves that maintain a high moisture content.
They include: Ajuga reptans (Carpet Bugle), Anemone nemorosa (Wood Anemone), Helleborus x hybridus (Lenten Rose), Iris x germanica (Bearded Iris), Liriope muscari (Turf Lily), Ophiopogon japonicus (Mondo Grass) and Stachys byzantina ‘Big Ears’ (Lambs Ears).
The lawn areas are planted with Stenotaphrum secundatum ‘Sir Walter’ (Sir Walter Buffalo Grass), a soft-leaf, hard-wearing turf species. It can be managed to a low height and will be irrigated over summer. This maintenance helps create a defendable space.
This includes raised beds of vegetables and a collection of small productive fruit trees. They include a Citrus limon (Lemon), Citrus reticulata (Mandarin), two Prunus salicina (Japanese Plum cultivars) and two Malus domestica (Apple cultivars). The vegetables and trees are all irrigated using water supplied from the adjacent steel water tanks.
Groupings of shade-tolerant evergreen shrubs are planted on the boundary of the garden’s middle terrace. They include Camellia sasanqua (Sasanqua Camellia), Daphne odora (Common Daphne), Strobilanthes gossypinus (Persian Shield) and Viburnum davidii (Davids Viburnum).
Their broad and fleshy leaves, open habit and coarse texture are low flammability characteristics. All shrubs will be pruned regularly to maintain their height to below 2 metres.
Close to the eastern side of the house are garden beds containing low-growing succulent plants. They include Aeonium arborium (Swartzkop), Aloe x spinosissima (Spider Aloe), Cotyledon orbiculata (Pigs Ears), Kalanchoe tomentosa (Pussy Ears), and Kleinia mandraliscae (Blue Chalk Sticks).