Lupinus arboreus
Yellow bush lupine is a fast-growing evergreen shrub native to coastal California. It bears lightly sweet-scented yellow spikes and tolerates wind and salt spray. It performs best in mild, frost-light coastal zones on sandy, sharply drained soils in full sun. Plants are short-lived but establish quickly and can stabilize sunny banks. In northern coastal dunes it can spread aggressively and alter soils through nitrogen enrichment.
At‑a‑glance
- Group/Class: Evergreen shrub
- Height × spread: 3-6.5 ft (1-2 m) × 3-6.5 ft (1-2 m)
- Bloom window: May to July
- Color & flower form: Usually yellow; erect racemes; lilac or purple forms exist
- Fragrance: 2 noticeable
- USDA hardiness: 8b to 9
- Breeder / Year / Origin: unknown, unknown, USA (coastal California)
- Pet safety: avoid
How it differs
- Woody and evergreen rather than herbaceous
- Tolerates coastal exposure and lean, sandy soils
- Flower fragrance is more noticeable than many lupines
- Can become invasive north of its probable native range
Strengths
- Quick cover and erosion control on sunny banks
- Handles salt spray and wind
- Drought tolerant once established
- Provides nectar and shelter for pollinators
Care in one minute
- Site: Full sun with exposure to air movement
- Soil and pH: Very well-drained, sandy soils; avoid rich amendments
- Watering: Deep but infrequent after establishment
- Feeding: Not needed; excessive fertility shortens life
- Grooming: Light prune after bloom; deadhead to reduce reseeding
- Region note: Avoid planting near sensitive dunes north of its native range
Watch‑outs
- Short-lived shrub that benefits from renewal planting
- Self-seeds freely; remove pods to limit spread
- Not reliably hardy in cold winters away from the coast
Best uses (tags)
coastal, banks, dry slopes, wildlife, low-water plantings
Provenance note
Likely native from the San Francisco Bay Area south to San Luis Obispo County; now naturalized along the Pacific Coast and overseas.
References
- Trees and Shrubs Online (International Dendrology Society): Lupinus arboreus (zones, habit, notes)
- California Invasive Plant Council: Yellow bush lupine plant report
- USDA PLANTS Database: Lupinus arboreus profile
Written by: Your Flowers Guide editorial team
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