Irises A Gardeners Encyclopedia

Around the world, approximately 270 iris species are known plus hundreds of subspecies, collected forms, and natural hybrids. All come from the Northern Hemisphere and can be found growing as far north as Scandinavia and as far south as Florida, from Europe to Japan, as well as in many parts of North America. Their habitats range from mountainsides to deserts, open grasslands, dense woodland, and sandy coastal areas. Irises grow from 5 to 200 cm (2 in. to 6 ft.) tall and bloom from late winter to late summer. With just a small selection, a garden can have irises in bloom from the dark days of winter until summer turns to autumn. Iris flowers come in a breathtaking array of colours ranging from white, yellow, and orange through every tone of blue, purple, pink, and brown to black. There are even green and red tones. All have six petals; the three upper petals are known as the standards, and the three lower ones as the falls. The base of the fall, the part of the petal that is narrower and constricted, is known as the haft or shoulder. The flowers bring into the garden not only colour but also scent. This fragrance can be fruity, musky, and spicy, like honey, and occasionally unpleasant. Irises also produce very handsome linear foliage that contrasts perfectly against plants with di=erently shaped foliage, such as lungworts (Pulmonaria spp.), elephant’s ears (Bergenia spp.), dead nettles (Laminum spp.), and hardy geraniums (Geranium spp.). Irises are easy to grow, tolerating a wide range of conditions from very cold climates, where winter freezes the ground hard, right through to subtropical climates. Some irises like bright sunny borders with well-drained soil, others grow in dappled shade, and a handful thrive in full shade. Although some irises like acid soil, most grow in soil that is slightly acid to alkaline. Some like poor dry, stony soils, others grow in damp soil. Perhaps the best-known irises are those that grow in water.