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How to: use water wisely

As the cost of water goes up, gardeners are looking for smart ways of making the most of this precious resource. 


Here are some new tools that help.

Grey water system

- Grey water is the wastewater from your washing machine, shower, bath and basins.

- A greywater diversion device enables untreated greywater to be used in a sub-surface irrigation systems.

- A greywater treatment system enables you to use treated greywater for above-surface irrigation, toilets and washing machines. Treated greywater can also be stored.

- Greywater is not permitted to run off your property.

- The Australian Standard requires that a sign be placed on the outlet of the greywater diversion device marked "WARNING DO NOT DRINK" and that all irrigation pipes be coloured purple.

- Some soaps and detergents are more harmful than others for your garden. Make sure they don't contain phosphates.

We had a Waterwise system installed five years ago and have seen been using the laundry water to drip irrigate part of the garden. A small holding tank was installed just outside the laundry and a drip irrigation system run down the garden along the driveway. This garden features maples, camllias and agapanthus, all doing brilliantly with the grey water.



This system takes the cold water that runs while you wait for hot water and diverts this clean water to a holding tank. We are planning to attach one to the kitchen tap and put the holding tank under the deck. It will cost $220, plus a plumber for half a day, plus the cost of the tank. This is a techno upgrade of simply using a bucket to catch the clean water as you wait for the hot water, which you can then throw on your neediest plants. You can find more details about Ecoverta at


Water probe

A water probe reduces water lost through evaporation from watering and gets the water to the plant roots where it’s needed. We use it on our trees setting it to drip into the root zone for 15 minutes around the drip line of the trees, moving it four-five times around the circumference. (The drip line is the futherest extent of the canopy of the tree; this is the area where the tree’s feeder roots are.)


Trigger nozzles

A trigger nozzle attached to your garden hose is an easy way to save water. Instead of hand watering your plants with the hose continually running water, a trigger nozzle with an on/off switch allows you to direct water when and where it is needed. This seven spray nozzle ranges from full force to a water-saving mist. You can change the shape of the fall of water, as well as its force and it can be regulated with a volume control dial on the unit.


Rain sensors

A common problem with watering systems pres-set to timers, including water-efficient drip irrigation, is that they switch on even when it rains. A rain sensor will turn your electronic controller off when it rains, while a soil moisture sensor detects moisture and switches off your watering system controller when your garden has sufficient water. Speak with your local irrigation installer about an appropriate sensor for your watering system.

Text: Linda Ross

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Author: Linda Ross