Forums DIY Controlling pond blanket weed? Reply To: Controlling pond blanket weed? May 21, 2018 at 2:35 pm #343 donna 10 Posts Excess nutrients will encourage blanket weed. Plant something like water mint, water forget-me-not. Both are pretty rampant plants and will help to use up the nutrients. A water lily can help too because its leaves spread over the surface and shade light from the water. Even the dreaded duck weed is pretty good at keeping the light out. I’ve used barley straw for a few years and found it to be good. I use the actual straw (available fairly cheaply in bundles from the Bay) rather than barley straw extracts. It does take time to work – up to 6 weeks – (and the plants will take time to grow too). Unfortunately the blanket weed has got the drop on you as it is already doing well. Removing blanket weed physically is easy, provided the pond isn’t too big, using a cane or big twig; rotate it and the blanket weed will get caught.