ARROYO LUPINE

In early spring, the purple hues of arroyo lupine in full bloom are commonly visible along California roadsides.

Next to the sunflower family, lupine--a perennial in the pea family--is among the largest family of plants, with more than 82 species. This species, also known as the foothill lupine, grows in heavy clay soil on dry, grassy slopes and hillsides in Southern California.

The plants grow to about 2 feet with seven to nine dark-green oval leaflets to each leaf. Leaves are 3/4 to 2 3/4 inches long. Flowers form small clusters on either side of the stem and are deep purple-blue, with a rusty red vertical zone with a yellow spot below. The blooms are 2 1/2 to 12 inches long, with a pea-like appearance. The arroyo lupine flowers from February through May.

The plant’s Latin name, Lupinus succulentus , derives from the word wolf; it is so named because of the belief that it robbed the soil of nutrients. Actually, this species adds beneficial nitrogen to the soil through its root nodules, but also can produce dangerous alkaloids contained primarily in its fruits.

Lupines are quick to recover after a fire. The Dayton Canyon fire of October, 1982, burned a meadow and sage hillside at the Reagan ranch near Santa Barbara. Four months later, the hillside and part of the meadow were densely covered with blooming arroyo lupines.