DuckweedText Box: DUCKWEED (Lemna minor) Very small bright green leaves. Rampant grower. Fish love it. Weather permitting Duckweed is shipped from April through July. Call for availability early and late in the season. We do our best to be aware of the plants not allowed to be shipped to your state, however, the responsibility is the buyers if your not sure check with your local USDA Office.