Tags
bombweed, epilobium angustifolium, fireweed, late summer wildflowers, medicinal uses of plants, rosebay willowherb, wildflowers of railway embankments
Stands of this glorious, showy plant may begin flowering as early as June, but are at their best now, gracing the margins of woodland, bogs, railway embankments and roadsides from June to September. A member of the Onagraceae family, Rosebay willowherb is native to the British Isles ; it is a vigorous perennial and can reach a height of almost 2 metres.
Rosebay Willowherb – Epilobium angustifolium Other common names include Fireweed, Bombweed and Ranting Widow. In Welsh it is Helyglys hardd.
Rosebay Willowherb was voted the County flower of London in 2002 following a poll by the wild plant conservation charity Plantlife.

The flowers are slightly unequal, notched and have 4 deep pink/purple petals, 15-25mm across that grow up a long spike
A hairy plant, it has oblong to lanceolate, coarsely toothed leaves. In autumn the downy seedpods split into four and release long plumes of featherweight hairs, which in warm dry conditions open up like parachutes, carrying the attached tiny light seeds great distances; each plant is capable of producing up to 80,000 seeds.
The flowers are a very good source of nectar for bees. Bee keepers sometimes move hives to newly opened forestry land where the plant is quick to colonize.
Etymology
The species name angustifolium is quite straightforward, simply made up of the Latin words angusti meaning ‘narrow’, and folium meaning ‘leaf’.
Nowadays Rosebay Willowherb is widespread and common across the British Isles, but as little as a century ago Rosebay Willowherb was a relatively scarce woodland plant and up until the mid-eighteenth century most writers seemed to consider it a garden plant which occasionally escaped into the wild. The first authoritative wild records are all from rocky or riverside sites.
The following are extracts from Richard Mabey’s Flora Britannica:
In Northumberland in 1769, rosebay could be found ‘Among the rocks and bushes under the Roman wall on the west side of Shewing-sheels, and by the Crag Lake. … It is introduced into some of our gardens under the name of French willow; but being a great runner, it makes a better figure in its more confined situation among the rocks, than under culture…. It is reputed a scarce plant. In Hertfordshire, in the 1840s, it was described as ‘rare’ in woods on a moist sandy soil, and in osier beds. Other noted botanists of the time, including the author of ‘Flowers of the Field (1853), the Revd C A Johns made similar reports.
But by 1867, the Worcester botanist, Edwin Lees, had begun to notice a change in its habits: ‘Quite recently the Rosebay Willow-herb has become numerous in several parts of the Vale of Severn, and promises to spread, incited to take possession of new-made roads and embankments. I have observed it by the side of a diverted road near Shatterford, and in the cutting of the Birmingham and Gloucester Railway, near Croome Perry Wood.’
‘Fireweed’ or ‘Bombweed’
During the First World War (1914-18), populations of rosebay exploded, especially where extensive woodland had been felled (and often burned) to supply timber for the woar effort. In World War 11, there was a second wave of expansion. Rosebay relishes areas where there have been fires, and the summer after the bombing raids of 1940, the ruins of London’s homes and shops were covered with sheets of rosebay stretching, according to some popular reports, as far as the eye could see and generating the popular name ‘bombweed’.
In Gloucestershire there were mixed feelings about the plant. In 1948 the new county flora edited by H.J. Riddelsdell says:
‘This species has spread with great vigour since about 1914 owing to the clearing of woods…. The seed is easily carried, of course, and the railway has been a great agent in its spread. Beautiful as the plant is in its flowering season, when it is in seed it creates desolation and ugliness over the whole of its area.’
Traditional Medicinal uses
The roots may be peeled, pounded gently and used as a poultice for skin damage such as burns, sores, swellings, boils and other similar afflictions.
An infusion of the leaves, drunk as a tea act as a tonic for the whole system, helping digestion and inflammation, but take moderately as they are also an effective laxative.
The dried pith may be dried and powdered and applied to the hands and face for protection against the cold.
Practical uses
In autumn the downy seed hairs can be used as fast lighting tinder (similar to thistle down), very effective with flint and striker. Make sure you have a secondary tinder ready as the down burns away quickly.
The down has been used to stuff mattresses and mixed with cotton or fur to produce warm clothing.
The fibre from the outer stem is used as a material for making cords.