Iris, a genus of perennial herbs native to temperate regions of the Northern Hemisphere. There are more than 200 species.

Most irises are 1 ½ to 4 feet (46 to 120 cm) tall, but dwarf irises rarely exceed 9 inches (23 cm). The leaves are sword-shaped and grow directly out of the ground. The flowers are white, yellow, pink, purple, blue, reddish, or two-colored. (The plant's name is from the Greek for rainbow.) Flowers grow singly or a few together at the tops of the stems. Each flower has three outer drooping petals (called falls); three inner upright petals (standards); and three stamens.

Among the many kinds of wild irises the blue flag is the most common. The chief types of cultivated irises are bearded, beardless, crested, and bulbous. The first three types are grown from rhizomes (rootstocks), bulbous from bulbs.

Bearded Irises

are identified by a beard (a pattern of hairs) that runs down the middle of each fall. These plants withstand both heat and drought well. One species is the fleur-de-lis, emblem of French kings and of the Boy Scouts.

The bearded irisThe bearded iris has a pattern of hairs down the middle of each petal-like fall.
Beardless Irises

which usually bloom in June, have smooth petals and thin, grasslike leaves. Common species are the Japanese and Siberian.

Crested Irises,

such as the dwarf crested, have a small raised crest, often of contrasting color, in the middle of each fall.

Bulbous Irises

are particularly well suited to hot summers and mild winters. Among the chief species are the English and Spanish irises.

Orrisroot powder is made from the fragrant rootstocks of several varieties of European irises, particularly the Florentine iris. The name orrisroot is a corruption of iris root. Orrisroot is used in the manufacture of perfumes and tooth powders.

The blue flag is Iris versicolor; fleur-de-lis, I. germanica florentina; Japanese, I. kaempferi; Siberian, I. sibirica; dwarf crested, I. cristata; English, I. xiphioides; Spanish, I. xiphium; Florentine, I. florentina. All belong to the iris family, Iridaceae.

Bulb Planting Chart.