How to Control Water Lilies in Farm Ponds
- 1). Prepare to spray the water lilies with herbicide on a cool day in early spring when the water lilies are beginning to show new growth.
- 2). Purchase an herbicide that contains glyphosate and is specifically approved for water lily control. An unapproved herbicide can cause long-term damage to the health of a pond. Glyphosate kills the vegetation it touches and becomes attached to the organic matter in the pond.
- 3). Mix the herbicide in a garden sprayer according to the manufacturer's instructions. Do not make the solution stronger than what is recommended on the label.
- 4). Wade into the water to spray the floating water lily vegetation, or apply it from the shoreline or a boat. Do not spray the herbicide into the water; it kills only the water lilies it contacts. Targeted water lilies should die within two weeks. Reapplication may be necessary in areas where growth is extremely heavy.
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