Water Hyacinth

South America

General description

Free-floating aquatic perennial. Distinctive swollen, bladder-like petioles attached to heavy, glossy, leathery leaves give buoyancy. Hyacinth-like flowers borne above foliage, pale lilac with purple markings, yellow spot.

Still or slow moving freshwater: ponds, streams, swamps. Frost-tender, mats tolerate moderate frosts.

Seeds & plant fragments dispersed by water, wind, machinery.Seeds viable for <20 years.

Aggressive plant chokes waterways displacing native flora. Twenty five plants can form 1ha mat over one growing season.

Site management

Report all sites to MAF.

Recommended approaches

Control under MAF direction.
1. Hand-pull small sites.
2. Spray (150ml glyphosate/10L, use glyphosate formulation approved for use over water).

Caution: when using any herbicide or pesticide PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.

Search tags

RPMS status

Surveillance - Whole Region
National Pest Plant Accord species - nationwide
water hyacinth - Main species image