[2] It is a hardy herbaceous tuberous perennial with a wiry stem that grows up to 3 metres (9.8 ft) tall.

The scarlet, funnel-shaped flowers are spurred and grow on long stalks from the leaf axils.

After the flowers fade, the red calyces persist, curling back to reveal the three blue berries.

It must be considered as such because during dormancy it generally retreats to a small underground tuber, where frost often does not penetrate.

This plant has gained the Royal Horticultural Society's Award of Garden Merit.