A spreading to erect shrub varying in height from 1.5 to 5 metres. Bark reveals yellow beneath when peeled. Twigs sometimes tinged purple, but not always. Leaves often opposite or sub opposite, linear-oblong, pointed, slightly bluish green, untoothed. Catkins appear before the leaves, 2 to 4 cm reddish or purple tinged, often opposite, and often curved.

Wet ground, marsh areas, wet ditch banks, water margins.

Catkins March and April (slightly later further north).

Deciduous.

Widespread throughout Britain and fairly frequent in some areas, particularly eastern England.

May be nearly scarce in Leicestershire and Rutland. In the 1979 Flora survey of Leicestershire it was found in 67 of the 617 tetrads.