Michael Smit, technical and sustainability manager at Kingspan Water & Energy, suggests rainwater harvesting as one of the most accessible ways to improve your home’s sustainability. “It also reduces the impact of increased population growth and climate change on urban stormwater, improving local waterway health and reducing flooding risks and costs,” he says.
Rainwater tank are a pretty simple retrofit, but you will need specialised advice and then tradie help to plumb one in and organise the pump system. A 5000-litre tank is the minimum useful size for an average garden – you’ll need a larger one if you want to connect to the laundry and toilet cisterns as well.
The grey zone
Greywater – indoor wastewater excluding that from toilets – can be reused via a simple dispersal device, but with caution. Greywater will often contain bacteria and viruses, so always disperse above ground, as sunlight will, to some degree, sterilise the water. Never disperse using a system that allows the output to mist. The trick is not to distribute too much to one area – waterlogging can occur and overload the soil with ingredients found in detergents. Check with your local council before using greywater, as many have tight restrictions on use, particularly in suburban areas.
A well-designed irrigation system delivers the right amount of water where it’s needed. A large multi-zoned system may need professional installation, but drip-line irrigation is a straightforward D.I.Y. project.
Even the best soil can have issues with water absorption. “Many water problems start at the surface of the soil – water can’t penetrate and runs off,” says Mark Ellis from garden products suppliers Scotts. Wetting agents, which come in liquids or granules, change the surface tension of water, allowing it to better penetrate the soil and reach plant roots.
A more labour-intensive fix is to dig in soil improvers such as compost or composted manures, improving the soil structure and increasing biological activity, which will naturally boost water-holding capacity. Mulching will help retain moisture in the soil and reduce run-off, while also diminishing soil erosion, suppressing weeds and insulating against temperature extremes. Spread your chosen mulch around 4cm thick and keep it at least 5cm away from plant stems or trunks.
Your garden’s water-wasting weakest link may be your hoses, fittings and taps.
- If you have a dripping tap, change the washer.
- Check hoses for leaks and replace or repair if needed.
- Tighten loose or leaking hose fittings.
- Check and replace the black rubber O rings on tap connectors, sprinklers and hose nozzles.
One of the foundations of sustainable gardening is selecting the right plants.
Try these dry-garden winners.
- Native grasses, such as dianellas and lomandras.
- Bromeliads, which come in varieties suitable for many climates.
- Agapanthus, very dry-tolerant thanks to their big storage root or rhizome.
- Olive, a classic originating from the Mediterranean.
- Variegated yucca, with its dramatic form and foliage – a natural statement-maker.
- Coastal rosemary, a fantastic, hardy Aussie native. It makes a great feature plant or low hedge.
Start water-saving in your garden
To get started, check out your local Bunnings, speak to one of our experts for more advice, and have a look at the range of water-saving products.