Dwarf Crested Iris is native to the Eastern and Southeastern parts of the U.S. The plant grows from 6 to 9 inches high with solid stems.

Leaves are narrowly sword shaped. Most are basal, usually 6 to 8 with lower ones sheathed with brown blades, the upper 4 or 5 green to yellow-green, not sheathed, up to 6 inches long, slightly curved and not prominently veined. These increase in length after flowering. with a raised (thickened) mid-rid, not prominently veined. The flower stem may also have 2 to 3 leaves.

The inflorescence consists of 1 or 2 flowers, at the top of a solid stem that rises from the root. Stems may have some 1 or 2 stem leaves. The upper section of the stem under each flower forms a greenish spathe covering the ovary of the flower. Stems are quite short, just reaching the tops of the leaves. Blooms are usually in mid to late May in Minnesota, depending on the early or late onset of Spring.

Flowers are about 1-1/2 to 3 inches wide when fully open; the perianth being blue, lilac-purple or white. The tube of the perianth widens as the flower opens. The 3 outward spreading drooping sepals (also called 'falls' in Iris terminology), which surround the true flower, each have 3 parallel, toothed, crested ridges on a white patch, tinged with gold, known as a 'signal,' which has a purple border, the sepal then tapers to a clawed (extremely narrowed) base. [In a "bearded" iris, this crest is replaced by the beard] The petals (called 'standards' in the Iris genus) are smaller than the sepals and curve upward and outward between the sepals such that from above both sepals and petals look like 6 spokes of a wheel. Petals are the same color with smooth margins.

The fruiting parts are in the center of the flower. The style forms flat petal like branches, usually called 'style arms' that are narrowly triangular and that reflex outward atop the base of the sepals and cover the anthers and sigma, providing rain cover for the pollen. The nectar of the plant is in glands at the base of the petals. The ovary, in the top of the spathe is 3-celled and triangular.

Fruit: Seed capsules are sharply 3-angled outlining the three inner chambers of ovary and the capsule remains within the spathe. Each chamber of the capsule usually has two rows of seeds, which are yellowish-brown at maturity, smooth, with a narrow white appendage wrapped around the seed. These are distributed by wind when the capsule opens.

Habitat: The plant spreads via branching rhizomes which have fleshy roots; it forms clumps as the rhizomes separate and the plant can rapidly spread. In its native habitat it is found on rocky wooded slopes, on bluffs and along streams, calcareous soil preferred with full sun to partial shade. The plant tolerated dry periods.

Names: The genus name, Iris, is after the Greek goddess of the rainbow. The species cristata means 'crested' or having 'tassel-like tips', all referring to the crests of the flower. The author name for the plant classification - ‘Aiton’ is for William Aiton (1731-1793), Scottish botanist, who succeeded Phillip Miller as superintendent of the Chelsea Physic Garden and then became director of Kew Gardens, where he published Hortus Kewensis, the Garden’s catalogue of plants.

Comparison: The most similar iris is the Dwarf Lake Iris, Iris lacustris, found in regions around the Great Lakes. The two are very similar and a recent paper by GARY L. HANNAN AND MICHAEL W. ORICK indicates that the I. lacustris emerged from the gene pool of I. cristata after glaciation. [American Journal of Botany 87(3): 293–301. 2000.] The other two iris remain in the Garden today are Blue Flag, Iris versicolor L. which is a our native marsh iris that is indigenous to the Garden, and the introduced Yellow Flag, Iris pseudacorus.