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Water Hyacinth


Water Hyacinth is a non-native perennial plant. It is free floating and grow up to 3 feet out of the water. Leaves are elliptical in shape and have a light blue to violet flower. The root system is very large and fibrous.

Other Names: Blue Shell, Shellflower

Mechanical Control

Water Hyacinth can be controlled by raking or skimming it off the pond's surface.

Chemical Control

Systemic herbicides, such as Shoreline Defense®, will work to kill the root of the plant.

Broad spectrum contact herbicides, such as Ultra PondWeed Defense®, will quickly kill any part of the plant it touches but multiple treatments may be needed throughout the season.

Chemical Application Best Practices

Anytime you use chemicals treat weeds and algae, please keep in mind the following:

  • Treat your pond in sections. Treat only half the pond's surface at a time, if the weather is hot, only treat 1/4-1/3 of your pond. Wait 10-14 days between treatments.
  • Once the weeds have browned, use a rake to remove as much dead material as possible. This prevents an accumulation of dead plant material and muck.
  • Treat your pond with the proactive approach to pond management. Use PondClear™, MuckAway™ and Pond Dye to keep your pond looking great.