Iris decora aka Nepal Iris

Iris decora is a perennial in the iris family, Iridaceae. It grows from tuberous parts below ground. Its native range runs from Pakistan to south-central China. Records also place it in Nepal, Bhutan, and northern India. It comes from temperate parts of this broad mountain region. It is not native to Britain or Ireland. Plants reach about 1 foot [0.3 metres] tall.

In the wild, it grows in dry inner valleys. It also inhabits grassy uplands, stony pastures, and cliffs. Recorded sites lie at 5,900–13,100 feet [1,800–4,000 metres] above sea level. This species is a beardless iris. Names have caused confusion in older accounts of the plant. PFAF links it with Iris nepalensis D.Don., also listed by RHS. However, Iris nepalensis Wall. refers to a different, bearded species. Checking the author after the name helps keep them apart.

PFAF gives July as the flowering month for this species. Each flower has both male and female organs. Insects pollinate the flowers, and the plant is self-fertile. It suits cultivated beds with a sunny, open site. Shade does not meet its growing needs. Give it rich soil that lets excess water drain away. Sandy soil and loam both suit it. It accepts mildly acid, neutral, and mildly alkaline conditions. The soil may be dry or moist.

PFAF recommends lifting plants in October for winter storage. Keep them in dry sand somewhere cool and frost-free. Plant them out again in March. Sow fresh seed in a cold frame once it ripens. The seed does not need a cold treatment. Sow stored seed early in the year. Grow young plants under cover through their first year. Move them outdoors in late spring or early summer. Divide established clumps after flowering in late summer. Large divisions can go straight into their growing site. Keep small divisions in pots until they root well.

PFAF records no known food uses for this species. It also records no other uses beyond medicine and garden planting. Traditional uses involve the root as a laxative and diuretic. Accounts also describe applying it to minor sores and pimples. These reports do not establish safe or effective home treatments. PFAF lists no weed potential for the species.