The Wild Blue Lupine Flower

Source: Photo by USFWS; Joel Trick

The Wild Blue Lupine flower belongs to the family of legumes. It is a is a perennial flower found much in the eastern United States.It is a popular ornamental plant in gardens. Regarding the color of the flowers, they are typically blue, but can also be white, shades of purple, violet. Occasionally they can be pink. They have 5 petals.The small (1-2½'' tall) bell-shaped flowers grow on a spike. The flower stalks are about 5 inches long. They have long, slender green leaves arranged in a whorl. The palmately compound leaves have 7-11 leaflets. The stems are light to reddish green and canescent-hairy.The plant can grow up to 2 feet tall.The seed pods are elongated and up to 2 inches long. Each pod contains on an average 15 seeds. As the pods dry, they twist and eventually pop open, shooting seeds in all directions. If you are in a patch of wild blue lupine when the seeds are drying you can hear the pods exploding.  They will sometimes pop open in your hands if you are collecting the seeds.

The plant was once thought to deplete or wolf the mineral content of the soil; hence the genus name derived from the Latin lupus (wolf). Quite contrarily, the plant and the family Fabaceae enhances soil fertility by fixing atmospheric nitrogen.

Blue lupine is the lone host plant for a little butterfly called the Karner Blue, an endangered species. The leaves of the wild lupine are its sole food. Habitat loss has led to the decline in plants, and put the Karner Blue on the endangered species list.When these larvae emerge in the spring they eat lupine leaves. The butterfly disappeared from Ohio when the lupines numbers start depleting.

All parts of the wild lupine flower are poisonous to humans, pets, horses and other livestock. 

The best place to see wild blue lupine flowers is at Kitty Todd Preserve. The annual Blue Weekend at Kitty Todd is a celebration of blue lupine and the Karner Blue Butterfly.