Lupinus nanus
Sky lupine is a petite annual native to California’s grasslands and open slopes. It is valued for compact, fragrant blue spikes with a white or yellow banner spot. Plants grow quickly from fall or early spring sowing and bloom in spring. They perform best in full sun and lean, very well-drained soils. The season is brief in heat, and plants reseed where bare soil is available.
At‑a‑glance
- Group/Class: Annual wildflower
- Height × spread: 6-20 in (15-50 cm) × 6-20 in (15-50 cm)
- Bloom window: March to May
- Color & flower form: Sky blue to deep blue; short vertical racemes of pea-like flowers with a banner spot
- Fragrance: 2 noticeable
- USDA hardiness: grown as annual in most regions
- Breeder / Year / Origin: unknown, unknown, USA (California)
- Pet safety: avoid
How it differs
- Much shorter than border lupines, suiting small spaces and containers
- Noticeably fragrant for a lupine
- Finishes the season early as heat arrives
- Best on lean soils rather than enriched beds
Strengths
- Fast from seed to bloom
- Fragrance and nectar for pollinators
- Low water needs in cool season
- Self-sows to return modestly
Care in one minute
- Site: Full sun with open exposure
- Soil and pH: Very well-drained, lean soils; neutral to slightly acidic
- Planting: Direct sow in fall in mild areas or early spring elsewhere; press seed to soil
- Watering: Light water for establishment; then minimal irrigation
- Feeding: Do not fertilize; inoculate seed if soil lacks rhizobia
- Grooming: Allow some pods to ripen if reseeding is desired
Watch‑outs
- Short bloom season
- Declines with summer irrigation or rich soils
- Seedlings need sharp drainage to avoid damping-off
Best uses (tags)
containers, meadows, rock gardens, pollinators, seasonal color
Provenance note
Native across much of California below about 4,300 ft, where it colors spring hillsides and roadsides.
References
- Lady Bird Johnson Wildflower Center: Lupinus nanus
- Calflora: Lupinus nanus taxon report
- Calscape: Lupinus nanus profile
Written by: Your Flowers Guide editorial team
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