Lythrum portula

Tracheophyta MagnoliopsidaLythraceaeLythrumLythrum portula


An annual of acidic or calcium-deficient silty soils at the muddy margins of pools and in temporarily flooded habitats such as rutted tracks, woodland rides, heathland pools and the draw-down zone of reservoirs. It avoids the most acidic and nutrient-poor soils and is rarely found over peat. 0-460 m (source of R. Teme, Herefs.).



World Distribution

European Temperate element.

© K.J. Walker, BSBI

Broad Habitats

Light (Ellenberg): 8

Moisture (Ellenberg): 9

Reaction (Ellenberg): 5

Nitrogen (Ellenberg): 3

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 3.8

July Mean Temperature (Celsius): 14.8

Annual Precipitation (mm): 1084

Height (cm): 8

Perennation - primary


Life Form - primary

Therophyte (annual land plant)

Life Form - secondary

Annual hydrophyte (aquatic therophyte)

Comment on Life Form

normally on mud exposed in summer (P & C 1994)



Clonality - primary

Little or no vegetative spread

Clonality - secondary

Shortly creeping and rooting at nodes

Count of 10km squares in Great Britain: 1262

Count of 10km squares in Ireland: 321

Count of 10km squares in the Channel Isles: 7

Atlas Change Index: 0.32

Weighted Changed Factor: 17

Weighted Change Factor Confidence (90%)


JNCC Designations


Atlas text references

Atlas (143b)
Atlas Supp (41a
Hultén E, Fries M
1986.  Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
Meusel H, Jäger E, Rauschert S, Weinert E
1978.  Vergleichende Chorologie der zentraleuropäischen Flora. Volume 2. 2 vols.
Preston CD, Croft JM
1997.  Aquatic plants in Britain and Ireland.