Water hyacinth

Water Hyacinth

Water hyacinth (Eichhornia crassipes) is a classified category 3 pest plant under Queensland's Biosecurity Act 2014. The species has already spread over substantial areas of the state. Its impact is so serious it must be actively controlled to avoid further spread to properties that are still free of the pest. It is identified as a Weed of National Significance.

It grows from 10 centimetres to one metre tall when nutrient levels are high. It has showy, blue and white irregular flowers. Seeds may germinate in a few days or remain dormant for up to 25 years.

Water hyacinth is a major pest within waterways. Its dense growth:

  • reduces fish populations
  • limits food sources for waterfowl
  • provides shelter for mosquitoes.

Our management of this pest species relies on mechanical removal and the application of registered herbicides. While biological control agents have been released in Australia, they cannot be relied upon to the same extent as the weevils on salvinia plants. Biological control agents for water hyacinth have reduced plant vigour and flowering, but they rarely build up to the high levels required to completely devastate the plant.

What you can do

  • Remove this plant from your ornamental ponds and water features, if you have them.
  • Check your watercraft and trailers are free of water hyacinth plants or offshoots.
  • Report sightings of water hyacinth to us.

For further information regarding management of this species, visit the Queensland Government's water hyacinth page, or alternatively please contact us.


Waterplants in Australia, G.R. Sainty and S.W.L. Jacobs, Sainty and Associates Pty Ltd, 2003.

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If you find a plant that resembles the characteristics of water hyacinth, click on the following button and scroll down to 'Pest plants' to complete our online form.

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