Native to South America, praxelis is an annual or short-lived perennial herb. Each praxelis plant produces hundreds of small black seeds.

Praxelis was first found in Queensland in 1993 and is now present in northern and eastern parts of the state. Praxelis infestations can invade crops, grasslands and conservation areas.

Praxelis is not a prohibited or restricted invasive plant under the Biosecurity Act 2014.

Scientific name

Praxelis clematidea


  • Annual to short-lived perennial herb, usually 40–80cm tall, but can grow to 1m.
  • Stems are hairy and brittle.
  • Leaves are opposite, 2.5–6cm long, 1.4cm wide, roundly triangular with acute apex, hairy, toothed along edges, with unpleasant smell when crushed.
  • Flowers are lilac-blue, 7–10mm long, 4.5mm wide, form clusters at ends of stems.


  • Prefers tropical and subtropical areas.
  • Found along roadsides and railways, and in disturbed areas and pastures.


  • Found in northern and eastern Queensland.

Life cycle

  • Flowers mostly during summer and autumn.
  • Each plant produces hundreds of small black seeds.



  • Invades native vegetation.


  • Invades pastures, where it can form dense stands that exclude other vegetation.

How it is spread

  • Seeds spread by water, wind, vehicles and animals.


Physical control

  • Hand-pulling of small areas is not recommended, as mature seed can drop off and increase infested area.

Herbicide control

  • Remove seed heads prior to spraying.
  • No herbicide is currently registered in Queensland; however, an off-label use permit (Permit No. 11463) allows use of various herbicides for control of environmental weeds in non-agricultural areas, bushland, forests, wetlands, and coastal and adjacent areas.

See the Praxelis fact sheet (PDF, 2.1MB) for herbicide control and application rates.

Legal requirements

  • Praxelis is not a prohibited or restricted invasive plant under the Biosecurity Act 2014. However, by law, everyone has a general biosecurity obligation (GBO) to take reasonable and practical steps to minimise the risks associated with invasive plants under their control.
  • Local councils must have a biosecurity plan that covers invasive plants in their area. This plan may include actions to be taken on Praxelis. Some of these actions may be required under local laws. Contact your local council for more information.

Further information