Longspur Lupine

Lupinus arbustus

Native to:
Canada, United States

📍 View on iNaturalist →

Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Fabaceae
Genus:
Lupinus
Species:
Lupinus arbustus
USDA Symbol:
LUAR6

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Forb/herb , Subshrub
Height:
90 cm
Light Requirements:
Full Sun
Drought Tolerance:
Medium
Bloom Months:
may,jun,jul
Bloom Colors:
blue, purple, white

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)
Caterpillars:
★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)

Keystone Species Ranking

Caterpillar Keystone:
★★★★☆ Butterfly & moth species supported by this genus (NWF)
Pollen Specialist Bee Keystone:
★★☆☆☆ Native pollen specialist bee species supported by this genus (NWF)

Host Plant for Caterpillars

Shasta Blue (Plebejus shasta), sooty hairstreak (Satyrium fuliginosum), Western Blue (Plebejus icarioides)

Reported Fauna Sightings

Bees: Yellow-faced bumble bee (Bombus vosnesenskii)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies

Soil Requirements

Soil Type:
sandy, well-drained, nutrient-poor soil
pH:
6.0 - 7.5 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
Commonly found in open, rocky areas

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Scarification:
Seed coat scarification required before sowing
Germination Time:
14–30 days
Notes:
Seeds benefit from scarification (nicking or hot water) followed by cold stratification.

Pre-treatment: Seed is moistened and inoculated with rhizobium and mycorrhizae. No scarification required.

Establishment: Lupine pods shatter when ripe, requiring collection while the seed is still green. As seed ripens pods become thin and change from green to yellow becoming somewhat transparent. Pods are ripe for harvest when individual seeds can be discerned when held against a light background. Harvested lupine seeds and pods have high moisture content and must be quickly spread out to dry.

Source: npn.rngr.net