Using Greywater in the Garden

Greywater, water from your bathroom sinks, showers, tubs, and washing machines, is an asset that most households see going ‘down the pipes’. The days of free water are over in a lot of the local councils in and around Brisbane. So it makes dollars and sense to divert greywater to your gardens.

Greywater systems will require council approval prior to installation, so check with your local council before purchasing property or making enquiries about system installations. The costs for systems vary depending on your requirements, but typically range between $700 to $2000. With average 4 person family water bills clocking in at $200 per 1/4, a greywater system makes perfect financial sense. Given our region’s history of drought, it also makes perfect sustainability sense too.

Some plantings in your garden may not be suitable for greywater irrigation; edible and sensitive plants for example. Not all greywater leaving your house is suitable for irrigation either. Greywater from heavily soiled work clothes and nappies are best not diverted to the gardens. Be selective about the water waste that is diverted to your greywater system. Gardens that are specifically designed to receive greywater may include plantings from of the following:-

  • Bird of Paradise
  • Melaleuca
  • Dietes
  • Gardenia
  • Callistemon
  • Confiers
  • Liriope
  • Yucca
  • Hibiscus
  • Manilla grass
  • Seashore Paspalum
  • Saltwater Couch grass
  • St Augustine turf*
  • Bermuda grass*
  • Buffalo grass*
  • Green Couch*

*Grasses and turf will prefer alternating irrigation between grey and clean water.

In order to maintain the health of your gardens once a greywater system is in place, you have to be more selective of the detergents and soaps used in the house. Sodium and phosphorus are common ingredients in washing detergents and both can have a detrimental effect. As a general rule, choose products that have no phosphorus and are low on sodium. In 2009, Lanfax laboratory published a list of washing detergents with corresponding levels of sodium and phosphorus.

Landscape Brisbane is glad to help make your garden more sustainable with greywater irrigation systems install and suitable plantings.