Information on Great Willowherb

Common Name: Great Willowherb
Scientific Name: Epilobium hirsutum
Irish Name: Lus na Tríonóide
Family Group: Onagraceae
Distribution: View Map (Courtesy of the BSBI)
Flowering Period


Click for list of all flowering by month
Great Willowherb could sometimes be confused with:

Willowherb, Hoary,

This is quite a robust, stout-stemmed and tall plant of damp places, ditches, riversides and generally unshaded places. Its downy stems bear leafy racemes of rose-pink (occasionally white - see lower picture), four-petalled flowers, each carrying the distinctive four-lobed stigma at its pale centre.  The flowers (15-25mm across) are bypassed in height by slender, hairy seedpods which split when ripe to release seeds attached to plumes of silky hairs.  The oval leaves of this plant are hairy and mostly opposite, clasping the stem. This plant makes a great display on the roadsides in July and August, almost like a herbaceous border gone a bit wild and is also a great source of nectar and pollen for bees.  Great Willowherb is a native plant belonging to the family Onagraceae. 

I first identified this plant in 1976 in Dalkey, Co Dublin and photographed it in Vicarstown, Co Kildare in 2004. 

If you are satisfied you have correctly identified this plant, please submit your sighting to the National Biodiversity Data Centre

Willowherb, Great
Willowherb, Great