Our pond suffers from blanket weed. I’ve tried all sorts of treatment, from chemical nastiness to barley straw, but nothing seems to deal with it. I’d love to fill our pond with plants, but they’d be consumed by the green peril. Is there any way to get rid of blanket weed, other than hoicking it out from time to time?
There’s no easy solution. The pond weed is doing too well, because the pond doesn’t have enough shade and is too rich in nutrients, so the chemical balance is out of whack. Removing debris from the bottom and keeping out excessive autumn leaves will help. Plant taller marginals, or even a tree, to give better shade to the pond.
I have had success in the past using the black dye, Dyofix, which dyes the water black, blocking the red end of the light spectrum that the blanket weed needs to grow well; it’s harmless to wildlife and plants, and contains no pesticide. This will also affect any plants that live under the surface, but lilies and reeds that poke above the water will be fine.
If you try all these remedies together and continue to pull out any bits of blanket weed, I think you may succeed.
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