- 1). Locate and identify the watercress. The plant roots in the stream or pond bed and has green leaves and clusters of white flowers extending above the water surface.
- 2). Determine if the watercress creates a problem for recreational use of the pond or stream. Left in place, the watercress plant does provide food for waterfowl and other wildlife.
- 3). Pull watercress plants located along shorelines by hand. Remove the plant material from the site. Pulled plants that wash back into the stream or pond could begin to grow again.
- 4). Pull larger patches of watercress with a garden rake or hoe. Pull up as much of the root structure as possible to prevent new growth.
- 5). Shade the area where the watercress was growing by placing a black plastic mesh over the area. Weight the mesh down with rocks. The mesh prevents light from reaching the watercress roots or plants, causing them to die. Keep the area covered for about two weeks before moving the mesh to another location in the pond.
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