Bushfires are becoming more frequent and often harder to control, making our homes and properties more vulnerable to fire than perhaps they once were. For those of us interested in protecting our properties, the call to plant fire-resistant plants is at an all-time high. If we can incorporate trees, shrubs and ground covers into our design which are slower to burn than some other species, while at the same time providing us with food and nourishment when it’s not bushfire season, then we can’t really go wrong.
There is a long list of trees and plants that can help us to provide a resilient layer of practical edibles that can help hold back encroaching wildfires. For those thinking of growing a fire-resistant boundary, here’s a couple of edible options across five different plant types that are well worth considering.
1. Large Trees
Chestnuts (Castanea sativa) are well-regarded for their fire resistance, as well as huge yields of nuts and quality timber. These trees hold a lot of water but have no volatile substances that will burn, making them excellent fire inhibitors. They grow well in warm temperate regions, though they do require good access to water, making them suited for companioning with swales and/or streams.
Another practical large tree is Carob (Ceratonia siliqua), which is a fire-resistant, nitrogen-fixing legume tree. It produces edible pods which can be used as a substitute for chocolate, and it makes great feed for livestock. It thrives in arid climates, particularly along the coast, and is a low-maintenance overstory in desert food forests. Once seasoned, it is well-regarded as fuel wood.
2. Small Trees
You only have to look at this powerful image to understand the fire resistance of a mulberry (Morus sp.) tree. The white, latex-like sap of the mulberry tree makes it withstand fire well. As well as providing delicious fruit, mulberry trees have edible leaves which are also used in silk production. Mulberries thrive in temperate climates, are widespread in arid regions and can be cultivated readily from cuttings.
In fact, fruit trees in general tend to hold a lot of moisture, which makes them really practical fire-resistant options. For areas that might lack the water a lot of fruit trees require, pomegranates, loquats and quinces are three choices that are less demanding.
3. Hedging Plants
Saltbush (Atriplex sp.) denotes several species across the globe, including Australia. It is used for sheep fodder, as well as erosion control and soil rehabilitation. Saltbush can grow in salted soils and retains the salt in its leaves. Many species are edible and have been a source of food the world over, mostly for indigenous people. Another fire-resistant plant which produces sweet edible fruit is the lilly pilly – Syzygium Aussie compact. A native rainforest species and with non-invasive roots, its small, glossy foliage responds really well to hedging and topiary. The compact variety grows to three metres high and around 1.5 metres wide.
Sage (Salvia sp.) is a highly aromatic, evergreen plant used in wintertime fare, spiritual ceremonies and desert landscapes. Sage is the largest genus in the mint family and, in addition to being used as a culinary herb, it is great for attracting pollinators and repelling pests. It’s a resilient plant that can be cultivated in a multitude of settings.
Rock samphire (Crithmum maritimum) is an edible, drought-tolerant succulent with a high moisture content which makes it less flammable than other plants. Sometimes called sea fennel, it thrives in sandy soils and, when found growing between rocks or in crevices along coastal areas, remains quite compact. It can, however, grow up to 50 centimetres high and as wide as one metre when conditions allow.
5 Ground Covers
Warrigal greens (Tetragonia expansa) is a fast-growing perennial native tolerant to both heat and drought. It’s commonly called New Zealand spinach, though unlike actual spinach it is susceptible to frost, and is cultivated as a vegetable. It grows well in sandy soils with salinity and has the reputation of being invasive if not contained.
Purslane (Portulaca oleracea), considered a weed, is edible and nutritious. It spreads across disturbed ground and can survive harsh conditions. Its succulent leaves are great at quelling fires. Purslane is one of the best sources of plant-based omega-3 fats and can be eaten raw.