What can you do to help manage weeds in Adelaide? Read on to find out.

Prickly pear (Opuntioid cacti) is a declared plant and cannot be sold anywhere in SA.

Prickly pear (Opuntioid cacti) is a declared plant and cannot be sold anywhere in SA.


Managing pest plants is one of the most complex of biodiversity challenges, even in cities.

Generally weeds are plants growing where they aren’t wanted. Some weeds become serious threats to the health of Adelaide’s natural environment.

South Australia has at least 1,300 weeds that have been naturalised. This means that these weeds are so widespread that we just have to live with them: think soursobs.

In South Australia, there are 140 “declared plants” that cannot be sold, grown or moved in the state like the water hyacinth. Some have exotic names too such as Chilean needlegrass, senegal tea or apple of sodom.

Top of the declared plant list are the “alert weeds” that are not yet established in South Australia and pose a serious threat. These are the ones that we really want to weed out to avoid the next big problem.

The job for Green Adelaide (and other landscape boards in SA) is to facilitate the management of weeds that pose the greatest threat, particularly to native plants that we want to preserve.

The job for all South Australians is to look after their own patch and to avoid making the problem worse. Landholders and managers are responsible for controlling weeds on their property.

Green Adelaide receives many reports of declared plants being sold online. So be wary about what you find on Gumtree and Facebook Marketplace. The simple solution is to check before you buy. PIRSA has a list of plants banned in South Australia.

Here’s some easy tips for you to weed out weeds in SA:

  • plant local native species in your garden
  • chat with your local council before you plant
  • dispose of your garden waste responsibly (many weeds today were garden escapes)
  • join a local conservation group to learn more about Adelaide’s natural environment.

Do you need help selecting the right plants for your backyard? Check out the interactive Adelaide Botanic Gardens ‘Plant Selector +’ guide for tips.

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