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Water Lily


Water Lilies have floating leaves that grow up to 10 inches, are split to the stem at the center, and are often purple underneath. Flowers are large, showy, and usually white (but sometimes pink or yellow). Water Lily flowers can remain open from morning until shortly after midday. Often planted as an ornamental, Water Lilies reproduce by rootstocks and seeds. Water Lilies prefer to grow in quiet water, less than six feet deep.

Mechanical Control

Water Lilies can be cut or the rhizomes can be dug up. It will be difficult to control this way because it will regrow from seeds and remaining rhizomes.

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 Weed Cutter 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.