Description
Silvery lupine is a common and widespread perennial lupine species found throughout large parts of the American West, sometimes in very large populations, and in parts of western Canada and Mexico. As the common name silvery lupine suggests, this species of lupine sometimes has narrow, silvery-green, palmate leaves — sometimes hairy in texture, sometimes not — that give the plant an overall silvery sheen, that accents the showy flowers, but it is also a highly variable species, with 12 different varieties throughout the West that can vary in size, shape and color.
The flower clusters have many flowers, sometimes arranged in whorls of varying shades of purple to blue flowers. The banner of the flower (top petal) may have a patch of white or yellow, or not. Silvery lupine grows .5-3′ high and 1-2′ wide. It will prefer to grow in full sun to part shade. It may not flower as well in deep shade. Bloom time depends on elevation, but at low to mid elevations in the Klamath-Siskiyou region it usually blooms May-June. At higher elevations it will bloom later.
Silvery lupine is in the pea (Fabaceae) plant family, and like other members of that family, it is nitrogen fixing. It forms a mutualistic relationship with bacteria that grow on its roots, helping it fix nitrogen from the air and fertilizing the soil. Because of this, lupine can establish itself in harsher areas.
Silver lupine grows well in the dryland garden setting, and is a popular species for native plant gardens and cultivated areas, as well as for habitat restoration. It adapts well to various soil types, including clay, loamy, sandy and rocky soils.
In the wild it can be found growing on slopes, ridges or in grasslands and meadows in mixed conifer forest, oak woodland, yellow pine forest, sagebrush scrub, and juniper woodlands. Although it grows in various places throughout the Klamath-Siskiyou region it is patchy in nature and less common than in other places in the West.
Bumble bees and other native bees are highly attracted to silvery lupine. It is a larval host plant for some butterfly species.
This species is toxic and no part of the plant should be eaten.
Note: Silvery lupine (Lupinus argenteus) differs from silver bush lupine (Lupinus albifrons), which we also sell seeds of, in that it does not have any woody stems, and it is deciduous, completely dying back to the ground in the winter; whereas, silver bush lupine is woody and evergreen.
Silvery lupine (Lupinus argenteus) seed packets contain approximately 40 seeds per packet.
Seed Germination Instructions
No pretreatment needed for fresh seed. Sow outside in fall to early spring. Stored seed may need scarification with sandpaper or a hot (not boiling) water treatment to help aid germination.