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Should I treat my pond weeds now, or will they die on their own now that it's getting colder?
ASKED BY: Ed of Norton, OH
ASKED BY: Ed of Norton, OH

Should I treat my pond weeds now, or will they die on their own now that it's getting colder?


A:  This time of year, many aquatic plants—including weeds—seem to be no longer actively growing. Triggered by dropping temperatures and fewer hours of sunlight, the cold-weather slowdown sends perennial plants into dormancy, and it can be hard to tell if they're dead or just holing up for the winter.

Because you'll see little or no greenery, treating those weeds can be a challenge. Plus, most chemical treatments, like herbicides and algaecides, don't work well in colder temperatures. Algae Defense, for example, stop working when the water is below 60°F, and the beneficial bacteria in PondClear almost slow down completely when temps fall below 50°F.

So what options do you have for treating weeds in the winter?

  • Rake Out Dead Vegetation: First, pull on your muck boots and gloves, and manually pull weeds and dead foliage from the water with a weed rake or other weed removal tool. This will take out growing plants and cut down on decaying organics, which means fewer weeds and fertilizer for them next spring.
  • Dose with Pond Dye: Next, add some Pond Dye to the water. Available in convenient liquid quarts, gallons and water-soluble packets, it will shade the water blue or black and reduce the amount of sunlight that reaches the bottom of your lake. Pond Dye can also be used regardless of the temperature or time of year.
  • Aerate the Water: Unless you plan to use your lake for winter recreation, make sure your Airmax Aeration System is up and running. It'll keep your water circulated, which will reduce the muck buildup throughout the winter, and it'll keep a hole open in the ice, which will allow for gas exchange. Your fish will thank you for it.

If you're concerned about weeds as fall and winter approach, give these three tricks a try. By removing existing weeds and reducing the decaying buildup (i.e. weed fertilizer) now, you'll have less work to do next spring—and won't that be a treat!