 Some of the plants growing in association with this species in the UK include water celery ("Apium inundatum"), marsh pennywort ("Hydrocotyle vulgaris") and lesser spearwort ("Ranunculus flammula").In its habitat in shallow water on pond margins or in poached wet grassland, it seems to grow well in bare locations where it faces little competition.Populations vary greatly from year to year; it sometimes "disappears" from a site only to recur there many years later, and cleaning out a ditch may stimulate it to reappear.