We planted a fair amount of Epimedium at our old house and had at least three different varieties with red, yellow, and white flowers. We only have a little here and all of it, unless I’m forgetting something, is the red Epimedium × rubrum, commonly called bishop’s hat) or red barrenwort, a cross between E. alpinum and E. grandiflorum. It’s easy to grow and the flowers are small but both lovely and borne prolifically and it’s certainly worth growing for the flowers alone. The leaves are quite nice, too, and even when not in bloom, it makes a handsome ground cover. In fact, we first saw it at the National Arboretum serving that purpose in a garden around a patio behind the gift shop.