Overview
A tall, robust, tap-rooted herbaceous perennial in the family Fabaceae (legume family), native to forest openings, mountain meadows, forest edges, and subalpine slopes from British Columbia south through Washington and Oregon to California, from low elevations to above 7,000 feet (2,100 m). The specific epithet latifolius means 'broad-leaved,' referring to the notably wide individual leaflets relative to many other native lupines. Plants grow 2–5 feet (60–150 cm) tall with palmately compound leaves bearing 6–10 broadly elliptic to oblanceolate leaflets 1.5–3.5 inches (4–9 cm) long, silky-hairy beneath. From May through July, erect terminal racemes 6–18 inches (15–45 cm) long bear numerous blue to blue-purple, pea-shaped flowers — whorled along the stalk in a pattern characteristic of lupines. As a legume, the roots bear nitrogen-fixing nodules, enriching the soil in the mountain meadow and forest opening communities where it grows. An important nectar plant for bumblebees, butterflies (especially blues and skippers), and other native bees. Safety warning: All parts of the plant contain quinolizidine alkaloids. Seeds are especially toxic and can cause lupinosis in livestock; ingestion by humans or pets can cause serious illness.
Native Range
Native to forest openings, mountain meadows, forest edges, and subalpine slopes from British Columbia south through Washington and Oregon to California, from low elevations to subalpine zones above 7,000 feet (2,100 m).Suggested Uses
Planted in native wildflower meadows, mountain garden borders, forest edge, and dry slope plantings at 18–24 inch (45–60 cm) spacing. The tall blue racemes May–July are visually striking and support exceptional bumblebee and butterfly diversity. As a nitrogen-fixing legume, functions as a soil improver in restoration plantings. Combines with Castilleja miniata, Penstemon species, and native grasses in mountain meadow and open forest edge designs. Keep away from children and livestock — seeds are toxic.How to Identify
Appearance
Size & Dimensions
Height2' - 5'
Width/Spread1'6" - 2'6"
Bloom Information
Blooms May through July for 4–6 weeks, producing erect terminal racemes 6–18 inches (15–45 cm) long of blue to blue-purple, pea-shaped flowers whorled along the stalk. An important nectar plant for bumblebees, native bees, butterflies (particularly lupine blues and skippers), and other pollinators. Seed pods ripen July–August — explosively dehiscent, ejecting seeds. Pods are hairy.Detailed Descriptions
Flower Description
blue to blue-purple; pea-shaped flowers whorled on erect terminal racemes 6–18 inches; May–July; bumblebee, native bee, and butterfly attraction; seed pods hairy, explosively dehiscent; TOXIC — all parts contain quinolizidine alkaloidsFoliage Description
medium green above, silky-hairy and paler beneath; palmately compound with 6–10 broadly elliptic leaflets 1.5–3.5 inches — latifolius means 'broad-leaved'; leaflets broader than most native lupinesGrowing Conditions
Sun Requirements
Requires 4-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Plant in full sun to partial shade in well-drained to dry, poor to average, acidic to neutral soil with a pH of 5.5–7.5. As a legume, fixes nitrogen and actually improves soil fertility — no fertilizer needed and rich soils may reduce flowering. Drought-tolerant once established. Direct sow in fall or early spring (seed requires scarification or cold stratification). Does not transplant well due to tap root. Self-seeds in suitable conditions. Safety: all parts contain quinolizidine alkaloids — seeds especially toxic to livestock and can cause illness in humans and pets.Pruning
Cut back after seed pods ripen and begin to shatter in late summer to prevent excessive self-seeding. Remove dead stalks to the base in fall or late winter. Do not disturb the taproot — plants resent division.Pruning Schedule
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summerearly spring