Using Grey Water in the Garden

recycling sign made of water splashes

With the general interest in conserving water and, consequently, also saving money, many are interested to learn how feasible it is to use grey water for irrigating lawns and gardens.

What exactly is grey water and how can it be reused?

Technically, grey water is household wastewater from the laundry and the bathroom (just the showers, baths, and basins, though). This may be reused to water domestic gardens. On the other hand, water that got flushed down the toilet and went down the kitchen sink is called black water, and it’s not suitable for reuse on account of its potentially high levels of bacteria, fat, and solid content.

Thanks to a growing public consciousness and resulting conscience about water conservation, many have begun diverting grey water from the house and into the garden to irrigate green spaces, not only during times of low rainfall and water restrictions, but year round. When it is done correctly, using grey water in the garden is, indeed, a superb way to save water and money.

The average Australian household of 2.5 people uses up about 124,100 litres of grey water each year. That’s more water than your standard garden needs in that duration of time. The other great thing about grey water is that there’s usually plenty of it throughout the year, provided the house is a primary residence.

There have been questions about the wholesomeness of using grey water in the garden, and the safest answer would be to proceed with caution since the quality and performance of grey water irrigation vary depending on a number of factors, such as the type of grey water used, the type of plants being watered, the soil structure and type, etc. Nonetheless, the following are the definitive instructions given by the experts.

Since it could contain germs from our bodies, do not use grey water to water vegetables and ground-welling herbs that are usually eaten raw. When it comes to fruit trees and vines, however, applying grey water is fine since there is no direct contact between the water and the fruit or part of the plant that is ingested.

As for general plantings, keep in mind that there are acid-loving plants out there, so you might not want to use grey water with detergents in it since these are often alkaline.


Don’t let these restrictions discourage you from reusing grey water. To ease your worries, however, you may want to consider a professionally installed, fail-safe grey water treatment system which will save you time and effort. It may also make you eligible for a rebate.


Contact Jim’s Mowing on 131 546 or book online for a free, no-obligation quote!