Persicaria hydropiper

Tracheophyta MagnoliopsidaPolygonaceaePersicariaPersicaria hydropiper


An annual of damp mud on the margins of ponds and lakes, canals, rivers and streams, or shallow depressions such as vehicle tracks and hoof-marks in woodland rides, around field gateways and in wet meadows. It is almost invariably in sites which are waterlogged in winter, often on base-poor soils and sometimes in partial shade. 0-505 m (Llyn Crugnant, Cards.).



World Distribution

Circumpolar Temperate element; widely naturalised outside its native range.

© M. Cotterill, IWNHAS

Broad Habitats

Light (Ellenberg): 7

Moisture (Ellenberg): 7

Reaction (Ellenberg): 6

Nitrogen (Ellenberg): 6

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 3.7

July Mean Temperature (Celsius): 14.8

Annual Precipitation (mm): 1093

Height (cm): 75

Perennation - primary


Life Form - primary

Therophyte (annual land plant)



Clonality - primary

Little or no vegetative spread

Count of 10km squares in Great Britain: 2041

Count of 10km squares in Ireland: 740

Count of 10km squares in the Channel Isles: 9

Atlas Change Index: -0.41

Weighted Changed Factor: -3

Weighted Change Factor Confidence (90%)


JNCC Designations