water pygmyweed
Crassula aquatica (L.) Schönland
Water pygmyweed belongs to the stonecrop family but lives at the water’s edge. Kew describes it as an annual or marsh plant, with a distribution reaching from subarctic and temperate northern regions into Central America. Its small size makes the details of leaves and flowers particularly important. Kew POWO: Crassula aquatica
Botanical name
Kew accepts Crassula aquatica (L.) Schönland; the catalog’s abbreviated author refers to the same species. Kew POWO: Crassula aquatica
Recognizing the plant
The northeastern flora describes branching plants only two to ten centimetres tall, rooting at the base. Narrow leaves spread from the stems, with opposite leaf bases joined around them. Solitary flowers sit in the leaf axils on almost invisible stalks. Usually four white petals form each flower, which is only about a millimetre wide. The fruits contain numerous tiny seeds. This is a complete flowering plant expressed on a remarkably small scale, with leaves themselves only a few millimetres long. World Flora Online: Crassula aquatica, Northeastern Flora treatment
Bloom window
Northeastern North America
The northeastern flora records flowering in late summer. World Flora Online: Crassula aquatica, Northeastern Flora treatment
Native range
Within northeastern North America, the flora places it on muddy coastal shores, often in the intertidal zone. Kew’s broader native distribution includes northern Europe and Asia, North America and parts of Central America. World Flora Online: Crassula aquatica, Northeastern Flora treatmentKew POWO: Crassula aquatica
Botanical sources
Reviewed 2026-10-11. Seasonal development varies with location and growing conditions.