In the last 2 years I have been seeing duckweed pop up on my pond. Considering it is 35 years old and this is the first I've seen it maybe I shouldn't complain. I use a skimmer net because my pond is small enough at under a 1/4 acre, but I think the culprit is nutrients. I do get an inflow most of the year but stocking and building habitat for fish has caused my fish population to bloom so I assume the fertilizer blooms as well. Skimming is easy because the aeration keeps it towards the shore and once you are ahead of it, it gets easier. But as much as I would love to eliminate it completely, without chemicals I don't see how it is possible. It is so easy to miss just a few plants and even if it all is eliminated, the spring duck visiting season surely will bring more.

Since the duckweed is so prolific, netting out a few pounds a day is also a method of removing biomass to keep it from sinking and decomposing on the bottom. I also set up a 6' diameter floating ring and early in the season add 3 or 4 water hyacinth plants. Within a month the ring is full to capacity and when the season is closing I just pull in the floating ring and compost the plants to get the biomass out of the system. Plus up north the cold winters will kill any hyacinths that escape the ring. I do save a few in the greenhouse to overwinter for next year.

Are there any other suggestions for harvestable plants to grow which can be easily removed at the end of the season to help consume the nutrient buildup?

I still do wonder how I escaped the plague of duckweed for so long.

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