Our plant of 'Violaceum' is a medium to tall form of E. grandiflorum which carries pink mauve flowers with paler spurs. We bought this from Beeches Nursery of Ashton, North Essex, and it has persisted well with us so far. Looking online, it would appear that it is probably a natural variant and the name should be written E. grandiflorum var. or f. violaceum.
General information on Epimedium grandiflorum
Distribution – Japan (Kyushu, Shikoku, Honshu and Hokiado). Northern Korea and southern Manchuria.
Description – A medium sized fairly deciduous species with widespread distribution through Japan etc. growing in deciduous woodland. It was introduced to Great Britain in the 1830s. With its wide geographical range through the various Japanese islands etc., a good deal of variation has occurred. Flower colour of the plants found in the wild varies widely: yellow, white, pink, lilac and reddish to purple. Add to this the large number of plants attributed to E grandiflorum that have arisen in cultivation and there may be hundreds of cultivars already named.
Epimedium grandiflorum 'Violaceum'