Irises compromise a very large plant group of more than 200 species. Our selection of irises are Siberian that grow from rhizomes. They have stiff, sword-shaped leaves and carry their colorful flowers on tall, stiff stems in spring and early summer. Iris flowers have six petals; three inner, vertical ones (standards), and three outer ones which curve outward (falls). The color range is very varied, covering blue, purple and lavender and many are bicolored. Rhizomatous irises contain several different groups, the most popular of which are the bearded, especially the Siberian. Bearded irises in general have large, very showy flowers with a short, bristly "beard" on the fall. Siberian, specially have delicate flowers and finer petals. Rhizomatous irises like a position in full sun, with protection from strong winds. Excellent plants for the middle to back of a mixed or herbaceous border. Bearded irises like a slightly alkaline, well-drained soil. Siberian irises need moisture-retentive, humus-rich loam soil.