Control Watermeal

Many people ask how to get rid of watermeal. Because the plant is so tiny, mechanical removal is exceedingly difficult. There is one reliable aquatic herbicide for watermeal control.

Click here to read more about identifying this plant.

Manual/Mechanical Control:

Skimming or mechanical means are often considered for how to remove watermeal. However, physically seining this plant is difficult due to its small size. Additionally, physical watermeal removal is often ineffective because watermeal can re-grow from any small plants/seeds remaining in the water that don’t get captured in the fine mesh net or removal device.

Herbicide Control:

There is an option for how to kill watermeal that offers great control.

1. Semera or Flumigard + surfactant (for ponds or lakes) – granules that are dissolved and mixed or liquids that are mixed and diluted with water and sprayed over every single plant (early morning is best), fast acting.
2. Spritflo fluridone (for ponds with no outflow) – liquid that is poured and spreads throughout the entire body of water. Fluridone is labeled for ‘partial control’ of watermeal. If you have positively identified watermeal in your pond, we do not recommend fluridone. If you can’t reach the pond with a sprayer, you could consider trying fluridone to obtain some watermeal control.

 Treatment Tips:

When treating watermeal,

• It is important to apply Semera or Flumigard evenly over all active plant growth; this plant can replicate rapidly from untreated or surviving plants.
• Re-treat when watermeal plants re-grow.