Rosebay willowherb

A patch of rosebay willowherb growing in front of a row of shrubby trees, with blue sky above. The willowherb has towers of pink flowers rising from a dense swathe of green leaves

Rosebay willowherb © Philip Precey

Rosebay Willowherb

©Ross Hoddinott/2020VISION

Rosebay willowherb

Scientific name: Chamerion angustifolium
A tall plant, Rosebay willowherb is a successful coloniser; it can form dense stands of bright pink flower spikes on disturbed ground, such as woodland clearings, verges and waste ground.

Species information


Height: up to 1.5m

Conservation status


When to see

June to September


The tall, pink flower spikes of Rosebay willowherb can often be seen crowding together in thick stands in open spaces, such as woodland clearings, roadside verges, grassland and waste ground. A successful coloniser, Rosebay willowherb has grown in number from a scarce woodland plant to a ubiquitous flower. This expansion occurred as a result of two World Wars clearing huge areas of forest and burning the ground in both town and countryside - just the right conditions for this plant to thrive in. One of its common names in the South East, 'Bombweed', alludes to this takeover.

How to identify

Rosebay willowherb is a tall plant with pink flowers rising up a flower spike. It has lance-like leaves that are arranged in spiral formation up its stem.



Did you know?

Rosebay willowherb is able to colonise new areas because of its specially adapted seeds - fitted with tiny, cottony 'parachutes' they are able to disperse across long distances on the slightest breeze. Each plant can produce up to 80,000 seeds and the heat from fires and bonfires can help to germinate them, hence another common name of 'Fireweed'.

How people can help

Although they might not look especially wildlife-friendly, our roadside verges, railway cuttings and waste grounds can provide valuable habitats for all kinds of plants and animals. The Wildlife Trusts are involved in many projects to make these places as beneficial for wildlife as possible. We have a vision of a Living Landscape: a network of habitats stretching across town and country that allow wildlife to move about freely and people to enjoy the benefits of nature. Support this greener vision for the future by joining your local Wildlife Trust.