Rheum palmatum var. tanguticum

A rhizomatous perennial to 2m high, with large basal leaves that emerge from the ground in late spring. Leaves are jagged and deeply cut, and dark reddish-purple when young, maturing to deep green with red undersides and long, thick reddish stems. In summer, tall, branching flower stems bear upright clusters of tiny, densely packed flowers in shades of white, pink or deep red