Excellent advice from Sarah Caldwell, Mole River Station Nursery
Cultivation of Australian Native Plants
Ground Preparation
Rip or cultivate the soil or maybe top with decomposed granite. Raise the beds if necessary. Add mushroom compost, if not Proteaceae or Australian pea species. Homoranthus and acacias appear to be better off without mushroom compost. Particularly correas and eremophilas love mushroom compost.
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Choosing suitable plants
Soil type
For heavy clay soils plant callistemons, melaleucas, westringias, eremophilas, grasses and eucalypts.
For lighter and sandy soils plant grevilleas, pea plants, hakeas, correas and banksias.
Many native plants can be grown successfully if the beds are raised to allow proper drainage to occur.
Foliage contrast is good eg Acacia baileyana purpurea, Acacia fimbriata dwarf & Rhagodia spumescent.
Water requirements
Ground cover grevilleas on the whole are not particularly drought tolerant. Frost hardiness: guards &/or blue metal can help.
Plants should not be pot bound; squeeze the pots to check they are flexible.
Temperature is important to many plants. On the whole, many species of the Myrtaceous family are quite heat resistant. This family includes eucalypts, leptospermums, callistemons and melaleucas. Lilies and grasses are frequently tough in the heat.
The plant family to avoid in hot areas is the Rutaceae family. This includes Correas, Boronias and Croweas. Many grow in granite soils on the tablelands in filtered shade.
Group plants with similar requirements together. Grevilleas and banksias without mushroom compost. Deep-rooting plants and eremophilas where they won’t receive extra water.
Planting
Save your pennies and plant all at once. It is particularly hard to plant later under eucalypts. They take the moisture out of the ground all year round unlike deciduous trees. Plant callistemons, some varieties of melaleucas, lomandras & westringias under established eucalypts – plants need a strong vigorous root system to establish. Grevilleas on the whole are not suitable under eucalypts as they have a limited life span. After they have passed on, it is difficult to grow anything else in their place.
Dig a large hole, add blood and bone and mix with the soil. Blood and bone is useful as it doesn’t turn grevilleas yellow and can be used for all native plants. lt also helps condition the soil and gets the microbes working. Plant also a large rock or log for a cool root run – especially useful for the Rutaceae family. Parts of the garden which only attract morning sun are always at a premium.
Fertilizer tablets can be effective. Agriform tablets last for 2 years. Plant the plant & water in thoroughly – 5 litres. Install a watering system. Mulch the bed – there are a variety of mulches to use. Lucerne hay is excellent for the soil but doesn’t last long. Grass mulch can be practical if baled after the seed has fallen. Weed mat keeps the ground moist but can waterlog plants during wet times.
Rock mulch – try road metal & rout. All the water sinks in, the rock insulates the soil & diminishes frost damage. Guard during winter frosts or heat waves. Milk carton guards with bamboo stakes can be made more effective by pushing loose soil half way up around the outside of the carton. A useful frost guard can be made using a white woven fertiliser bag and 3 stakes to hold it up. lt may be installed with the closed end at the top.
Pruning
When a plant is first in the ground, tip prune frequently or give haircuts. From one year old they may just need one pruning annually so prune during November or after the plant has flowered. Try to encourage shoots from the base. Remove about 1/3 of the plant; any dead limbs, spent flowers or seed heads. This will prolong the life of the plant & stop it from falling over. lt is important not to prune all the small side branches from a tree as this can create an unstable plant.
Deficiencies
The most common deficiency when growing native plants is iron deficiency. The leaves turn yellow around the margins first and finally go black. This is very common with grevilleas and banksias in neutral to alkaline soils. lron chelate is readily available from nurseries. Add 2
teaspoons to a l-litre watering can of water and water around the base of the plant. Rinse off the leaves with clean water afterwards as the iron can burn the foliage.