Dietes is a genus of rhizomatous plants of the family Iridaceae, first described as a genus in 1866. Common names include wood iris, Fortnight lily, African iris, Japanese iris and Butterfly iris, each of which may be used differently in different regions for one or more of the six species within the genus. Most species are native to southern and central Africa, with one (Dietes robinsoniana) native to Lord Howe Island off the coast of Australia. A few species have become naturalized in other parts of the world.