A clump-forming perennial with upright stems and narrow, dark green leaves that are flushed reddish purple, especially when young. Yellow-green flowers are produced at the tips of the stems in late spring and early summer. Foliage retains some red colouring throughout the summer, especially on the backs of the leaves, and colour deepens to near black as the temperatures drop in autumn.
Height & Spread 1m (3ft), 2-5 years to maturity.