Epilobium parviflorum Seeds | Hoary Willowherb

Minute, pale brown Hoary Willowherb seeds with fine silky hairs, on a plain background — Hoary Willowherb (*Epilobium parviflorum*): Onagraceae, native to damp meadows and stream banks across Europe and western Asia.

LATIN NAME: Epilobium parviflorum

COMMON NAME: Hoary Willowherb

Plant Profile

Hoary Willowherb is a slender, softly grey-hairy perennial, usually 30 to 80 cm tall, with narrow leaves and small pale pink flowers just under a centimetre across. It flowers from July to September, later and more discreetly than its larger relatives, and the seed pods that follow split into four valves to release plumes of white hair.

It is native to damp meadows, stream banks and ditches across Europe and western Asia and has been carried to North America, where it is now widespread. The whole plant is covered in fine hairs, which is what gives it both its English and its Latin name.

Science & Biotechnology

The species is one of the Epilobium taxa most studied for its phenolic content. Oenothein B, a macrocyclic ellagitannin, is the compound most often quantified, together with myricetin and quercetin glycosides, and extracts of the herb have been examined in laboratory and small clinical work on benign prostatic hyperplasia.

As with other willowherbs, the seed is wind-dispersed and needs bare, damp ground to establish, so the plant behaves as a pioneer of wet disturbed sites rather than as a persistent weed of closed grassland. It hybridises with Great Willowherb where the two meet, and the offspring are hard to place without close examination of the stigma and flower size. Seed set is heavy in a wet year, and a single stem can carry several hundred capsules.

Uses & Benefits

Hoary Willowherb has been a household herb in central and eastern Europe for generations, drunk as a tea for prostate and urinary discomfort; it is still sold for that purpose in pharmacies in Germany, Poland and the Czech Republic. The tea is mild and slightly astringent, and the whole aerial part is used.

In the garden it is a plant for a damp wild patch, where its pale flowers light up the shade in late summer and its seed heads feed small birds. It is not showy enough for the front of a border, but it earns its place among meadow grasses and beside water. It also makes a reasonable ground cover beneath fruit trees in a damp orchard, where its late flowers bring hoverflies in.

Growing from Seed

Sow on the surface of a moist, fine compost in spring and press the seed in without covering it; light is needed for germination. Keep the tray at 18 to 20 °C and never let the surface dry out; seedlings usually appear within two to three weeks.

Plant out into any soil that holds moisture, in sun or light shade, and water through the first summer. The plant self-sows generously once established, so a single introduction will usually persist and spread; remove the seed heads if that is not wanted. Cut the stems back in autumn or leave them standing for the birds.

Our Take

A modest plant with a long medicinal record and a useful late-summer flower for damp places. Easy from seed, generous with itself, and never troublesome where the ground stays wet.

Herb Seeds