Iris Cruella

The species is the Japanese roof iris, once planted along the ridges of thatched roofs in Japan where its roots helped hold the thatch together. 'Cruella' is the variegated form, and it forms a slow, tidy clump rather than running about. Settled plants send up a steady succession of blooms over several weeks, each one lasting only a day or two.

Drainage counts for more than rich feeding. Set the rhizome so its top sits level with the soil surface and keep mulch clear of it, or it will rot in a wet spell. Slugs go for the soft young leaves in spring, so watch for them early. Lift and divide the clump every three or four years to keep it flowering freely.