Range: Southern coastal British Columbia south to northwestern Baja California
This miniature lupine is known by several names, including, literally, Miniature Lupine, Bicolor Lupine, Lindley’s Annual Lupine, Pygmy Lupine, or just Annual Lupine. A West Coast native, this species inhabits dry or well-draining open spaces such as meadows, rocky hillsides, or disturbed patches of land from sea level to almost 3,000 meters (though most commonly below 1,000 m). Plants tend to grow to a maximum of 45 cm tall (not including the inflorescences), with a short, pubescent stem from which leaves up to 8 cm long sprout semi-alternately, eventually forming a mildly bushy radial growth pattern. The leaves consist of a long, pubescent narrow petiole, ending in a peltate spread of oblanceolate leaflets numbering 5-9 typically, the smallest leaflets toward the center of the plant and longer distally. The stems may occasionally branch, and each branch will end in an inflorescence up to 8 cm tall, tipped in a dense cluster of long green or reddish bracts that shelter the flower buds. The cluster lengthens as the flowers and eventually pods develop, each bloom with an upward-curved top lip and two clasping lower lobes that form a “keel” surrounding the reproductive structures. Coloration is typically a rich indigo-blue to indigo-violet, the upper lobe with a lighter central patch that opens white and may remain white as the flower ages or may darken to pink or light violet. Pea-like seedpods develop afterward, containing between 1-6 small, hard seeds. Several varieties have been described, though are of questionable validity.
Cultivation: Grow in a rich but well-draining potting soil (will tolerate and enrich poor soils however), kept only just moist to mildly damp (avoid being soaking wet, but don’t allow to dry out completely). Temperatures should remain above freezing throughout the intended growing season, as plants will die when frost hits, but this species can tolerate temperatures reaching 100°F with some protection or shade. Sow seeds just below the soil surface; very old stored seeds may benefit from a light scarification or treatment with a brief hot water soaking. Grow in bright dappled light to full sun.
Lifespan and reproduction: annual. Reproduces through seeds only.
Vegetative growth habit of L. bicolor. During hot or windy periods the leaflets may fold up closed to reduce moisture loss.
Close-up of flowers, showing the very hairy calyces (much like the rest of the plant) which protect the buds, and multi-colored nature of the flowers as they age.
The same flowers frequently change color with age; opening white on the highlights, these spots often age to pink or purple.