rhizomatous barrenwort

E. rhizomatosum is a clump-forming rhizomatous perennial up to 45cm high, with evergreen leaves of long, heart-shaped, spiny-edged leaflets up to 6cm long, which emerge mottled with deep red in spring and mature to green, and stems up to 30cm long of spidery flowers, 4-6cm across, of white or red sepals and pale yellow petals with long, broad spurs, in spring, and sometimes from early summer to early autumn; Epimedium leaves may be used for their nests by leaf-cutting bees