• 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

Centaurea montana 'Amethyst in Snow'

perennial cornflower 'Amethyst in Snow'

  • Other common names perennial cornflower 'Amethyst in Snow'

  • Family Asteraceae

  • Genus Centaurea may be annuals, perennials or subshrubs, with simple or pinnately lobed leaves and showy thistle-like flowers-heads, often with enlarged outer florets

  • Details 'Amethyst in Snow' is a spreading, herbaceous perennial with grey-green foliage covered in silvery hairs. The thistle-like flowers, white with purple centres, open from scaly buds in late spring and early summer

Characteristics

  • Foliage Deciduous

  • Habit Mat forming

  • 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)

    H7

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Exposed or Sheltered

Soil

  • Loam

    Loam

  • Chalk

    Chalk

  • Sand

    Sand

  • Clay

    Clay

  • MoistureMoist but well-drained

  • SoilLoam, Chalk, Sand, Clay

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Best grown in moist but well-drained soil in sun or partial shade. May need staking

Propagation Propagate by division in spring or autumn

Suggested planting locations and garden types Flower borders and beds Cut Flowers Cottage & Informal Garden Prairie Planting Coastal Patio & Container Plants

How to care

Pruning Deadhead regularly to prolong flowering, and cut back in autumn

Pests Generally pest free

Diseases May be affected by powdery mildews

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