Liquidsquid I bought 10 packages, 100 plus plants that run just short of $100 with shipping. I planted about 8' apart around my 1 acre pond. It seems to take a month before the plants started to spread. If they were very invasive I don't think they would be too much of a problem since they are short and stay under water. I don't think they can grow in deeper water where the sun can't reach them but that's just a guess. We'll see what happens this summer.
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