Grey water in the garden in a nutshell


"Consider the needs of the plants when watering with grey water"

Grey water can be either 'diverted' or 'treated' depending on how it is to be used. See Grey water recycling in a nutshell for more information.

Consider these points when watering with grey water:

  • Don't overwater. Just because you have it - you don't have to use it.

  • Check the drainage. Unless your plants are adapted to boggy soil you might kill plants with too much water.

  • Check the soil to make sure the water is being absorbed and is not running off.

  • Water the roots, not the leaves.

  • In the interests of health, consider using grey water first on ornamentals, then on fruit trees, and then use the fresh water you saved on vegetable crops.

  • Apply water with predictable frequency to reduce stress on the plants caused by a pattern of too much / too little water.
  • Apply water slowly and gently to avoid mechanical damage to plants and soil, and to reduce runoff.

  • Minimize the risk of plants receiving toxic quantities of elements by using as 'environmentally friendly' laundry products as possible. A very useful guide is Lanfax Laboratories' report on phosphorus and sodium levels in laundry products.

  • Occasionally water with freshwater to prevent the build up of salts in the soil.

  • An irrigation system might provide an effective and easy solution for larger gardens.

Recommended reading

Common Grey Water Errors and Preferred Practices by Oasis Design
US - Oasis Design: 2009
http://www.oasisdesign.net/greywater/misinfo/index.htm

Fact Sheet: Grey Water by Gardening Australia
Australia - ABC: 2005
http://www.abc.net.au/gardening/stories/s1366316.htm

Gardening with greywater by Waterwise Queensland
Queensland - Natural Resources and Water: 2009?
http://www.derm.qld.gov.au/waterwise/gardening/pdf/gardening_with_greywater.pdf