The habitats where duckweed~(Lemna minor) grows:

Chalk river and stream
Coastal floodplain grazing marsh
Fast flowing river and stream
Lowland fen
Marginal and inundation
Moist damp verges and banks
Nutrient rich eutrophic lake
Pond ditch and canal
Purple moor grass and rush pasture
Reedbed
Sluggish river and stream
Turlough and fluctuation mere
Upland spring flush
Wet woodland