Camassia is a late spring flowering bulb with large spikes of flowers in blue, purple or white. Commonly offered for sale are C. cusickii, quamash, and Leichtlinii.
Camassia bulbs should be planted in the autumn, at least 10cms (4") which is about 3 times the bulbs depth on well-drained soil which does not become waterlogged.
The flowers are lily like, with coloured stamens and the plants are tall growing to around 1-1.3m. The bulbs originate from North America growing along-side streams and damp meadows, from which it follows Camassia will tolerate damp conditions, but not boggy conditions.
Although described as hardy, (H4 which is hardy in most of the UK) Camassia will benefit from some winter protection by covering with a mulch. Camassia are best planted where they are to remain as Camassia dislike being moved and root disturbance. That said, Camassia are easy to grow and tolerant of most conditions excluding very shady or wet conditions.
Camassia will tolerate dappled shade and look ideal in a woodland setting. The leaves are slow to die down, like Alliums, do not look ideal especially after the flowers have faded, and this needs to be taken into account when making a planting arrangement. Bearing in mind the flowering time in May good companions are the early flowering Alliums, early flowering Geraniums and Aquilegia.