Control Water Hyacinth

While the flowers of water hyacinth can be considered pretty, this plant spreads so rapidly that it can overtake an entire pond in a few weeks. Water hyacinth is considered invasive in many states in the south where it acts as a perennial, growing back each year from seeds and existing plants. In northern climates, such as Minnesota, water hyacinth is unable to overwinter and management may not be necessary. However, Michigan has labeled water hyacinth as an invasive species. The following options can be considered for how to control water hyacinth.

Click here to read more about identifying this plant.

Manual/Mechanical Control:

If you are considering how to remove water hyacinth, physically raking or seining this plant can be an effective method of control. Because it reproduces from daughter plants, getting every plant out of the area can prove successful.

Herbicide Control:

There are multiple options for how to kill water hyacinth that offer great control.

• Dibrox (for ponds or lakes) – liquid that is diluted with water and sprayed directly on the plants, fast-acting.
• Cattail and Water Lily Control (Imox + surfactant) (for ponds or lakes) – liquids that are mixed and diluted with water and sprayed on the emergent parts of the plants.
• Liquid 2, 4-D (for ponds or lakes) – liquid that is diluted with water and sprayed on the plants and over the water where the plants are. Most effective on treatment areas larger than a half acre, this allows longer contact exposure time.

Treatment Tips:

When treating water hyacinth,

• Treat when the plants are established and actively growing.
• With Imox or other systemic herbicides, treatment is most effective when the plants are mature or close to full grown. This allows for more plant surface to spray enough mixture on.
  • Treat in late summer to early fall to get better kill of the root systems. At this time, plants are pulling energy into their roots to store for the winter.