A perennial herb growing on exposed mud at the shallow edge of still or slow-flowing waters, or in marshes and swamps. It is confined to mesotrophic or eutrophic habitats. Plants fruit prolifically, and the species is a frequent colonist of newly cleaned ditches and recently flooded mineral workings. Generally lowland, but reaching 405 m at Dock Tarn (Cumberland).
A well-recorded species with a distribution which is similar to that in the 1962 Atlas.
Circumpolar Wide-temperate element; widely naturalised outside its native range.