• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

Camassia quamash

common camassia

  • Other common names common camassia
    bear's grass

    camas
    camash
    camass
    camosh
    North American wild hyacinth
    quamash

    see more
  • Synonyms Camassia esculenta Lindl.
    Camassia teapeae

  • Family Asparagaceae

  • Genus Camassia are bulbous perennials with narrow, channelled leaves and erect racemes of star-shaped violet-blue or creamy-white flowers in early summer

  • Details C. quamash is a clump-forming bulbous perennial, growing to 80cm tall, with long, narrow basal leaves. In late spring and early summer, upright stems bear a dense spike of star-shaped blue flowers, up to 7cm across

  • Plant range W US to Montana

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Hardiness

    Hardiness ratings

    All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

    • H1a - Under glass all year (>15C)
    • H1b - Can be grown outside in the summer (10 - 15)
    • H1c - Can be grown outside in the summer (5 - 10)
    • H2 - Tolerant of low temperatures, but not surviving being frozen (1 to 5)
    • H3 - Hardy in coastal and relatively mild parts of the UK (-5 to 1)
    • H4 - Hardy through most of the UK (-10 to -5)
    • H5 - Hardy in most places throughout the UK even in severe winters (-15 to -10)
    • H6 - Hardy in all of UK and northern Europe (-20 to -15)
    • H7 - Hardy in the severest European continental climates (< -20)

    H4

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Aspect South-facing or West-facing or East-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilSand, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in moist but well-drained, deep, humus-rich, fertile soil. Intolerant of waterlogging and may need some protection from frosts in colder areas. Very good for naturalising in meadows

Propagation Propagate by seed sown in pots in a cold frame as soon as seed is ripe. Remove offsets when dormant in winter- see bulb propagation

Suggested planting locations and garden types Banks and Slopes Flower borders and beds Underplanting of Roses and Shrubs Cut Flowers Cottage & Informal Garden Wildflower meadow

How to care

Pruning Cut back faded flower spike unless collecting seed

Pests Generally pest free

Diseases Generally disease free

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