• 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

Cirsium rivulare 'Atropurpureum'

plume thistle 'Atropurpureum'

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
  • Other common names plume thistle 'Atropurpureum'

  • Family Asteraceae

  • Genus Cirsium may be biennials or perennials with spiny leaves and typical thistle-type flower-heads

  • Details 'Atropurpureum' is an upright perennial forming a clump of branching, leafy stems with spherical, deep red flower-heads 3cm across in summer

Characteristics

  • Foliage Deciduous

  • Habit Columnar/Upright

  • 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

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

  • Exposure Exposed or Sheltered

Soil

  • Loam

    Loam

  • Chalk

    Chalk

  • Sand

    Sand

  • MoistureMoist but well-drained

  • SoilLoam, Chalk, Sand

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1-1.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in a moist but well-drained soil in full sun; can tolerate some dryness and partial shade

Propagation Propagate by seed sown in pots in a cold frame in spring or propagate by division in spring or autumn

Suggested planting locations and garden types Flower borders and beds Cut Flowers Cottage & Informal Garden Wildlife Gardens Wildflower meadow

How to care

Pruning If self-seeding is a problem then cut back hard after flowering

Pests Generally pest free

Diseases May be infected by powdery mildews

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