A dioecious scrambling perennial herb with a massive, tuberous root-stock. It grows on well-drained, often base-rich, soils in hedgerows, scrub, woodland borders, and on rough and waste ground. It is unpalatable to rabbits and can be locally frequent around warrens. Lowland.
There has been no substantial change in the distribution since the 1962 Atlas. The limits of its native distribution are remarkably stable.