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I thought I did a successful chemical treatment, but why are the weeds coming back?
ASKED BY: Barney of Andalusia, AL
ASKED BY: Barney of Andalusia, AL

I thought I did a successful chemical treatment, but why are the weeds coming back?



A: Treating weeds is a tricky task. Despite dosing them with aquatic herbicides to clear your pond or lake of plant pests, they seem to grow back over and over again. It seems like a never-ending cycle! Why does this happen?

Well, chemical treatments have their benefits and drawbacks: On one hand, they work great as a quick fix to decimate actively growing weeds. But once those plants die, they become a food source for future weeds and algae, acting as a fertilizer for the very things you're trying to get rid of. The herbicides do nothing to prevent future growth, and so you're left with yet another growth spurt of pondweeds, which you'll then treat with chemical herbicides – and around you'll go again.

So how do you break the cycle? Here is a four-step approach that will help put an end to it.

  1. Remove the Dead Weeds: Once the weeds have browned, use a Razer Rake or PondSkim Debris Skimmer to remove as much dead material from the water as possible. This prevents dead plant material and muck from accumulating and fertilizing future weed growth.
  2. Be Proactive: Debris will still find its way into your pond, so add some beneficial bacteria to the water to manage the excess nutrients before they feed your weeds. The products found in the ClearPAC Plus Pond Care Packages – including PondClear and EcoBoost PRx for suspended debris, and MuckAway for accumulated bottom-of-the-pond debris – naturally break down that organic material.
  3. Add Aeration: If you don't have one already, install a Airmax Aeration System that's sized for your pond or lake. By circulating and adding oxygen to the water column, the beneficial bacteria will thrive. In turn, they'll eat through even more debris and prevent weed and algae growth.
  4. Shade and Color:  Pond Dye is another offensive tactic in your battle against aquatic weeds. Pond dye shades the water, preventing ultraviolet light from reaching the plants.

Throughout the spring and summer, weeds will grow. But with some pond management practices, you can keep those pesky plants to a minimum.