Frequently Asked Questions
21. How do you get a dense shrubby native garden in the shade of big gum trees?
A good question!!
It's not easy but it can be done. You will need to be persistent because plants growing in shade where water stress is likely to be a problem are often more open in habit than if they were growing in a more favourable position. There are two main considerations:
- A reliable water supply
- Choice of appropriate plants
As a guide, consider the following suggestions:
◄ Previous ◄◄ FAQ Index Top ▲
- Resist the temptation to build up a garden bed in the root zone of the trees. To be effective the bed would need to be built up by about 400 to 500 mm and this may have long term detrimental effects on the mature trees.
Plant the garden in autumn (the earlier the better) to give plants the longest possible period before the next summer. This also coincides with the period of least root activity by the trees.
- Dig holes for each plant at least twice the diameter and twice the depth of the root balls.
- Saturate the hole 2-3 times and allow the water to drain away.
- Mix some slow release fertiliser (at the recommended rate) with the soil when planting. Take care to use low phosphorus formula if phosphorus sensitive plants, eg. banksias, are to be used.
- Apply a dressing of Multigro (N:P:K 10:3:6) in early spring and again in late summer, making sure that the soil is wet when applied and water in well after application.
- Set a pot or tin (with holes punched in the bottom) next to each plant with the rim at ground level - this allows hand watering so that water gets directed to the roots of the plants.
- Plant a couple of "indicator plants" which show early signs of water stress. These can let you know when watering is needed for the garden as a whole. For example many Prostanthera species (mint bushes) wilt markedly when stressed but recover quickly when watered.
- If possible install drip irrigation to each plant (into the pot or tin) so that water can be delivered at regular intervals either automatically (via a timer system) or manually.
- Choose plants which tolerate some shade and dryness and which are suited to your climate. Plants such as commonly available grevilleas are probably not ideal but some of the smaller banksias would be worth trying. You can find lists in references such as Grow What Where by the Australian Plant Study Group and The Encyclopaedia of Australian Plants - Vol 1 by Elliot and Jones. You will also find helpful advice in Australian Native Plants by Wrigley and Fagg.
- Finally, the use of a good thick mulch would be advantageous.