Hydrilla is a perennial plant that forms dense colonies and can grow to the surface in water over 20 feet deep. Hydrilla branches profusely and after reaching the surface it extends across it forming thick mats. Hydrilla can reproduce by fragmentation, from seeds, from turions (axillary buds), and from tubers. Leaves are blade-like about 1/8 inch and 3/8 inch long with small tooth margins and spines on the underside of the midrib that make them feel rough. Leaves are usually 4 to 8 in a whorl.
Other Names: Elodea
Pond Dye can be used to limit sunlight into the pond. With reduced sunlight, photosynthesis cannot occur so growth will be stunted.
There are several options to control Hydrilla:
- Use a season long herbicide such as Sonar™ A.S.. One treatment treats Hydrilla and many other common pond weeds for the season.
- Use a broad spectrum contact herbicide, such as Ultra PondWeed Defense®, will quickly kill Hydrilla. Because it does not stay in the water body, multiple treatments may be needed throughout the season.
- Use Clipper™, a fast and selective herbicide that controls tough invasive and nuisance aquatic plants.
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.
Pond Logic® Ultra PondWeed Defense® Aquatic HerbicideBroad Spectrum Pondweed Control Fast Acting Liquid Formula Short Term Control Of Duckweed Pond Logic ® Ultra Pondweed Defense ® works on pond weeds including submerged, floating and emergent weeds. It may be used for short term control of...Read More »$49.99–$149.99
Hydrothol® 191 Granular Aquatic Algaecide & HerbicideFast-Acting Granular Formula Great For Bottom Growing Algae & Chara Control Weeds Surrounding Docks & Shorelines Hydrothol-191 provides rapid-acting contact control for submerged weeds and algae. Hydrothol-191 even works where there is...Read More »$119.99