Overview
Camassia cusickii is a clump forming, columnar upright bulbs in the genus Camassia, part of the Asparagaceae family, with deciduous foliage. It typically grows around 0.5-1 metres tall and 0.1-0.5 metres wide, reaching full size in around 2-5 years. Camassia cusickii grows best in full sun and partial shade, and tolerates most soils and any pH. Its UK hardiness is rated H4. Suggested uses include wildflower meadow, coastal, cottage and informal garden and prairie planting. It is native to NW USA.
About
Camassia cusickii is a bulbous perennial that typically reaches heights of up to 100 cm. It develops a dense cluster of long, narrow green leaves. In late spring to early summer, this plant produces erect spikes adorned with star-shaped, blue flowers.
About the genus
Camassia is a group of bulbous perennials characterized by slender, channelled foliage and upright clusters of star-shaped flowers that range in color from violet-blue to creamy-white, typically blooming in early summer.
Growing conditions
Best soil and position for Camassia
- Sunlight
- Full sun, Partial shade
- Soil type
- Chalk, Loam, Sand
- Soil pH
- Acid, Alkaline, Neutral
- Soil moisture
- Moist but well-drained, Well-drained
- Aspect
- West-facing, East-facing, South-facing
- Exposure
- Exposed, Sheltered
- UK hardiness
- H4
Plant details
Camassia cusickii size, habit and characteristics
- Plant type
- Bulbs
- Habit
- Clump forming, Columnar upright
- Foliage
- Deciduous
- Height
- 0.5-1 metres
- Spread
- 0.1-0.5 metres
- Time to full height
- 2-5 years
- Suggested uses
- Wildflower meadow, Coastal, Cottage and informal garden, Prairie planting
- Native to
- NW USA
- Toxicity
- Ornamental bulbs - not to be eaten. Wear gloves and other protective equipment when handling. Pets: Ornamental bulbs - not to be eaten - see the HTA guide to potentially harmful plants for further information and useful contact numbers
Care notes
Pruning and caring for Camassia cusickii
- Cultivation
- Grow in moist but well-drained, humus-rich, fertile soil. Intolerant of waterlogging and may need some protection from frosts in colder areas. May have the potential to become a nuisance due to prolific self-seeding if not managed well This plant was part of the RHS Camassia (quamash) trial 2024-2026
- Pruning
- Cut back faded flower spike
- Propagation
- Propagate by seed sown in pots in a cold frame as soon as seed is ripe. Remove offsets when dormant in winter
- Pest resistance
- Generally pest-free
- Disease resistance
- Generally disease-free
Frequently asked questions
How do I grow Camassia cusickii?
Grow in moist but well-drained, humus-rich, fertile soil. Intolerant of waterlogging and may need some protection from frosts in colder areas. May have the potential to become a nuisance due to prolific self-seeding if not managed well This plant was part of the RHS Camassia (quamash) trial 2024-2026.
Where is the best place to plant Camassia cusickii?
Camassia cusickii prefers full sun and partial shade. It suits exposed and sheltered positions.
What soil does Camassia cusickii need?
Camassia cusickii is adaptable and grows happily in most soil types, including chalk, loam and sand. It is happy in soil of any pH. Aim for soil that stays moist but well-drained to well-drained.
How do I prune Camassia cusickii?
Cut back faded flower spike.
How big does Camassia cusickii grow?
Camassia cusickii reaches a height of 0.5-1 metres and a spread of 0.1-0.5 metres. It takes around 2-5 years to reach full size.
Is Camassia cusickii hardy in the UK?
Camassia cusickii has a UK hardiness rating of H4.
How do I propagate Camassia cusickii?
Propagate by seed sown in pots in a cold frame as soon as seed is ripe. Remove offsets when dormant in winter.
Is Camassia cusickii toxic?
Ornamental bulbs - not to be eaten. Wear gloves and other protective equipment when handling. Pets: Ornamental bulbs - not to be eaten - see the HTA guide to potentially harmful plants for further information and useful contact numbers.