A branching, shrubby, hairless perennial. Flowers pure white, up to 1 inch long, with the typical 5-petalled "pea flower" configuration (1 banner petal above, 2 wing petals to the sides, and 2 fused petals below that form a keel), each flower with its own short stalk, arranged in erect or curved racemes. Blooms May–July. Leaves alternate, all along stems, divided into 3 leaflets; leaflets narrow, oblong, 1–3 inches long, with rounded tips. Stems smooth, covered with a glaucous (gray-white) coating.
Height: to 5 feet or more.
Habitat and Conservation
Occurs on prairies, fields, glades, rocky open slopes, valleys, roadsides, and streamsides. Prefers moist areas.
The foliage of this species has been used as a poor substitute for indigo dye. Although several insects eat it, white wild indigo is poisonous to mammals, including humans and livestock. This bushy plant, once established, is a strikingly beautiful native species for landscaping.
Several insects pollinate the flowers or eat the foliage. Most remarkable is the wild indigo dusky wing (Erynnis baptisiae), whose larvae feed only on this species. This butterfly's range and extremely local occurrence, in prairies and forest edges, coincides with the presence of its food plant.