Great willow herb is a tall perennial wildflower that can reach up to 2m in height. It flourishes on damp ground, such as wet grasslands, ditches, riversides and woodland clearings.
It produces a large number of bright pink flowers between June and September. The flowers are visited by many insects and the leaves are eaten by the elephant hawkmoth.
The seeds are produced in long pods that remain after the flower dies back. When ready the pods split down their length revealing thousands of tiny seeds with their own individual downy parachutes. These seeds can be carried hundreds of metres by the wind.