Overview
Lupinus arboreus is a shrub in the genus Lupinus, part of the Fabaceae family. It typically grows around 1.5 m tall. Lupinus arboreus grows best in full sun, and tolerates sandy and loamy soils. Its UK hardiness is rated H5. Suggested uses include coastal gardens and wildlife gardens. It is native to W USA.
About the genus
Lupinus, commonly known as lupin, lupine, or regionally bluebonnet, is a genus of plants in the legume family Fabaceae. The genus includes over 199 species, with centres of diversity in North and South America. Smaller centres occur in North Africa and the Mediterranean.
Wikipedia contributors, "Lupinus", CC BY-SA 4.0 — Lupinus
In the garden
Lupinus arboreus is a shrub from the west coast of the United States that forms a compact, flowering plant of roughly 1.5 m. Its summer display runs from June to August and the blooms are scented, so place it where the fragrance can be enjoyed. It favours full sun and will perform best in sandy or loamy soils that drain freely or remain moist but well-drained; exposure should be sheltered and a south-facing aspect helps ripen growth and flowers. Plant in a position protected from strong, cold winds to suit its sheltered exposure, and allow room for its mature height when siting near patios or mixed shrub borders. It carries a UK hardiness rating of H5 (hardy), so it tolerates ordinary winter conditions in most UK gardens provided the site is not overly exposed. Recommended uses include coastal gardens and wildlife gardens where a south-facing, sheltered nook is available. Take care handling plants: they are harmful if eaten, and toxic to pets if ingested, so wear gloves and other protective equipment during planting and pruning. For best effect, position Lupinus arboreus where its scented summer flowers can be experienced from a south-facing patio.
Growing conditions
Best soil and position for Lupinus
- Sunlight
- Full sun
- Soil type
- Sandy, Loamy
- Soil moisture
- Well-drained, Moist but well-drained
- Aspect
- South-facing
- Exposure
- Sheltered
- UK hardiness
- H5
Plant details
Lupinus arboreus size, habit and characteristics
- Plant type
- Shrub
- Height
- 1.5 m
- Suggested uses
- Coastal gardens, Wildlife gardens
- Native to
- W USA
- Fragrance
- Flower
- Toxicity
- Harmful if eaten. Wear gloves and other protective equipment when handling. TOXIC to pets if eaten (dogs, cats, rabbits, tortoises) - see the HTA guide to potentially harmful plants for further information and useful contact numbers
Care notes
Pruning and caring for Lupinus arboreus
- Cultivation
- Prefers sandy, well-drained soil; drought tolerant once established; avoid heavy clay soils
- Pruning
- Prune after flowering to maintain shape and encourage bushiness
- Propagation
- Seed, Cuttings
Frequently asked questions
How do I grow Lupinus arboreus?
Prefers sandy, well-drained soil; drought tolerant once established; avoid heavy clay soils.
Where is the best place to plant Lupinus arboreus?
Lupinus arboreus prefers full sun. It suits sheltered positions.
What soil does Lupinus arboreus need?
Lupinus arboreus grows best in sandy and loamy soil. Aim for soil that stays well-drained to moist but well-drained.
How do I prune Lupinus arboreus?
Prune after flowering to maintain shape and encourage bushiness.
How big does Lupinus arboreus grow?
Lupinus arboreus reaches a height of 1.5 m.
Is Lupinus arboreus hardy in the UK?
Lupinus arboreus has an RHS hardiness rating of H5, meaning it is hardy in most of the UK, tolerating -15 to -10°C.
How do I propagate Lupinus arboreus?
Seed, Cuttings.
Is Lupinus arboreus toxic?
Harmful if eaten. Wear gloves and other protective equipment when handling. TOXIC to pets if eaten (dogs, cats, rabbits, tortoises) - see the HTA guide to potentially harmful plants for further information and useful contact numbers.
From the Fenn Plants journal
- Notes on DaffodilsWhen to plant daffodil bulbs in the UK, how deep, how to naturalise them in grass, why daffodils stop flowering (“blindness”), and why you should never mix cut daffodils with other flowers.
- Keeping Your NerveHow to garden through a heatwave — the best time to water, why deep soaks beat daily sprinkles, caring for pots and vulnerable plants, and why you can let the lawn go brown.
- Made to LastHow to clean, store and protect garden pots and planters — the frost-proof vs frost-resistant difference, winter care for terracotta and ceramic, and how to reuse a broken pot.
More in the Lupinus genus
- Lupinus albifronssilver lupine
- Lupinus polyphyllusbigleaf lupin
- Lupinus polyphyllus 'Downer's Delight'Large-Leaved Lupine
- Lupinus polyphyllus 'Pink Pearls'Garden Lupin
- Lupinus albifrons var. douglasiiSilver Lupine
- Lupinus ornatusLupin