Q: Can Aquatic Weeds Go Dormant?
Jackie – Kalamazoo, MI
A: Yes, those insidious aquatic weeds can go dormant in the cold season, lying in wait in your lake’s muck and sediment, until spring when the hours of sunlight and temperatures increase. The good news is that you can battle them – even in their overwintering state. Here’s how.
When temperatures drop and the sun hovers lower in the sky, you’ll start to see those aquatic weeds retreat and hole up for the winter. The duration of their dormancy will depend on where you live (the weed growth patterns in a California pond, for instance, will differ from those in a Minnesota pond!). But, in general, you can expect to see different pond weeds disappear and reappear at different times of year based on environmental temperatures.
If your pond or lake freezes over, the perennial weeds will typically die back in the winter and re-emerge in the spring. Some plants, however, will continue to grow throughout the cold season, though at a much slower rate than you’d see in the warmer summer months.
Controlling Winter Weeds
Because you’ll probably see little to no greenery growing, it will be a challenge to control winter weeds. Methods that work in the spring and summer – like treating with temperature-sensitive herbicides and algaecides – won’t work in the colder temperatures. So what can you do? Here’s what we recommend:
- Remove Weeds: If there’s no ice on your pond, you can pull on your hip waders and manually remove the weeds with a Weed Raker. This go-to tool efficiently pulls out aquatic weeds by their roots, slowing their regrowth, and also removes decaying matter.
- Pond Dye: Pond Dye, available in convenient liquid quarts, will shade the water blue or black and reduce the amount of sunlight reaching the weeds and algae growing at the bottom of your lake. Less sunlight means fewer weeds, regardless of the temperature or time of year.
- Aerate the Water: If you’re not using your lake as an ice rink, crank on your Airmax® Aeration System. The action created by the aerator will circulate the water and reduce the muck buildup throughout the winter.
- Feeding Fish: Your fish will enter into a semi-dormant state when the water dips below 50 degrees, so there’s no need to feed them. Doing so will add to the lake’s nutrient load (i.e. weed fertilizer …), which is not what you want to do.
If wintertime weeds are taking over your pond, consider trying some of these time-tested tricks. They’ll minimize the nuisance growth during the cold season and reduce the amount of work you’ll need to do in the spring.
Pond Talk: How do you handle aquatic weeds in the wintertime?