Iris siberica

Native to Central and Eastern Europe and to Central Asia, where it grows in wet meadows and along watercourses, Iris sibirica is a rhizomatous, beardless iris (section Sibiricae). Its rhizome forms dense clumps of narrow, upright, blade-like leaves and flowering stems reaching 60 to 120 cm. In May and June it bears several flowers per stem in shades of blue-violet to purple, occasionally white, finely veined on the drooping falls. It thrives in moist, rich, acidic soil, in full sun to part shade, and tolerates waterlogged conditions. The rhizome should be planted shallowly and divided regularly.