Lupinus perennis var. perennis

Native

Dry to moderate moisture. Prairies, open woods. Full to partial sun.

May to June

Blue

8″ to 24″

This is a 8″ to 24″ tall, erect, perennial forb that rises on numerous stems from a well-developed taproot.

In its first year of growth this produces a rosette of basal leaves. In the second year it sends up several leafy, flowering stems.

The stems are more or less erect, slightly hairy, and marked with fine, vertical, parallel lines.

Stem leaves are alternate on ¾″ to 2⅓″ long leaf stalks. They are palmately divided into 7 to 11 leaflets. The leaflets inversely lance-shaped with the attachment at the narrow end, ¾″ to 2″ long, with a blunt tip. The upper surface is hairless. The lower surface is thinly hairy. The leaf stalks are longer than the leaflets.

The inflorescence is an erect, 4″ to 8″ long cluster at the ends of the stems. The clusters are unbranched, sparsely flowered, and cone-shaped at the top.

The flowers are about 1″ long and pea-like. The 5 petals are blue varying to pink and white, and are organized into a banner, 2 wings, and a keel formed by two petals fused together at the tip. The upper petal is shorter than the wings. The keel has a marginal fringe of hairs

The fruit is a yellow-grayish-brown, hairy, oblong, flattened pod with 5 or 6 seeds.

Bigleaf lupine (L. polyphyllus) reaches 40 inches at maturity. Its leaves are divided into 11–17 leaflets with pointed tips. The inflorescence is densely flowered.

This is the only plant used as food by the larva of the endangered Karner Blue butterfly.