They’re lovely to look at, but Water Hyacinth (Eichhornia crassipes) is an aquatic pest weed that we want to keep out of our region.
We understand that this plant may already be present in the community, so it’s very important that any discoveries are reported so they can be removed and disposed of safely.
Because of its aggressive, fast-growing nature, water hyacinth is one of the world’s most serious water weeds. It can rapidly form dense mats over water, smothering and out-competing other aquatic plants by blocking light and monopolising space.
It can block waterways causing flooding and irrigation issues, and reduce water quality, affecting the whole aquatic ecosystem.
It consists of a floating rosette of shiny, thick, rounded green leaves, with feathery roots that hang in the water.
A single flowering stalk with a cluster of pale lilac flowers, each with a single yellow spot, is produced from the rosette. Plants produce floating horizontal stems from which new plants arise.
Because of the potentially catastrophic impacts of this pest in New Zealand, MPI runs a national eradication programme for water hyacinth.
Under the law, it is classed as an unwanted and notifiable organism and cannot be legally grown, shared, displayed or sold in New Zealand.
If you think you have water hyacinth on your property or have seen it in the District, please contact our Biosecurity Team on 03 543 8400 or biosecurity@tasman.govt.nz, or MPI on 0800 80 99 66.
