The description on hillkeep says:
[quote]Iris laevigata F. E. L. von Fischer. Rabbit-ear iris. Yanzihua (China). Kakitsubata (Japan). Subgenus Limniris, Section Limniris, Series Laevigatae. Flowers that are blue to mauve to white, often with white or yellow central markings, bloom in May-July, depending on altitude. This is an elegant and reliable plant for shorelines and shallow ponds. Native to Russia, China, Korea and Japan. Our plants are from wild and garden seed from both China and Japan.
I would hope the RHS knew the image contributor had it correctly named, but as always you can never be sure.
