Getting the right garden design
What’s the secret to a gorgeous garden? It’s all in the planning.
If you’ve been wondering why your neighbour’s garden is flourishing while yours is looking a little sad, the secret may be more than just green fingers. A glorious garden rarely happens by accident; it usually stems from great planning.
So if you’re new to garden planning or you’re ready for a complete redesign, read our tips on what to plant, where to plant it and how best to take care of your plants so that they thrive in Darwin’s tropical climate.
What to plant
Planting water efficient native plants
Give yourself the best chance of success by choosing plants already suited to the local conditions. Ask your local nursery for advice on plant selection or check out Water Efficient Native Plant List for recommendations on plants best suited to the Darwin region.
Planting water efficient exotic plants
If you'd prefer a garden with tropical exotics like frangipani's, palms and bouganvillia's then make sure they are water efficient! See below for a Water Efficient Exotic Plant List and ask your local nursery for advice.
In Darwin’s tropical climate, mulch is critical to your garden’s success. Rich organic mulches are vital for plant nutrients, maintaining soil quality and to prevent erosion.
In the wet season, mulch is essential to keep plant roots cool, water in the soil and weeds down. Water logging is also a problem and raised mulched beds will assist drainage.
In the dry season, mulch application is an efficient water conservation strategy. Water loss from the soil by evaporation is minimised or eliminated and the germination and growth of weeds, which also consume water, can be greatly restricted.
If used in conjunction with a poor irrigation system or incorrect scheduling, mulch will not provide the expected savings. Some organic fine mulches have the capacity to intercept and hold considerable amounts of water, acting as a barrier. Both light rainfall and irrigation water applied as small droplets from sprays and microsprays can be prevented from entering the underlying soil by a layer of fine mulch.
The main types of mulch in use include stone, organic mulches, both fine and coarse and soft mulches such as cane and pea straw.
Key mulch tips
- Mulches should have more than 80% of their particles larger than 5mm
- Mulch should be applied about 50mm thick
- Savings from mulch are in the range of 10-20%
Where to plant
Well-structured zoning means placing plants with similar water needs together, so that they are all on one irrigation line. You can then control the amount of water that goes to plants on different lines. If zoning is poor, e.g. if citrus trees and natives are on the same line, the citrus will be under-watered and the natives will be over-watered.
Grouping plants with similar water needs together is called hydrozoning. You can have multiple zones in your garden, where each zone can supply plants with the same water needs with the appropriate amount of water.
Local influences on climate can be more significant than the climate itself. Imagine a west facing wall in the afternoon sun exposed to a hot dry wind. Contrast this with a south facing area, heavily shaded by overhead trees, protected from the wind and next to a pond or small watercourse.
Consider shade, wind and thermal radiation from buildings when planning your garden design and you could reduce your water consumption in the garden by half.
With thanks to Water Use Efficiency for Irrigated Turf and Landscape by Geoff Connellan, CSIRO Publishing 2013.