• 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

Echinacea purpurea

black samson

  • Other common names black samson
    hedgehog cone flower

    purple cone flower
    purple daisy
    eastern purple coneflower

    see more
  • Synonyms Rudbeckia echinacea purpurea
    Rudbeckia purpurea

  • Family Asteraceae

  • Genus Echinacea are erect, clump-forming rhizomatous perennials with simple or pinnately lobed leaves and solitary, long-stalked daisies with prominent conical central disks and often drooping ray florets; attractive to butterflies

  • Details E. purpurea is an upright perennial with coarsely hairy, ovate or lance-shaped leaves and solitary flower-heads to 12cm across with slightly reflexed, light purple rays and brown central disk

  • Plant range C&E North America


  • Foliage Deciduous

  • Habit Clump-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)




  • Full Sun

  • Partial Shade

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

  • Exposure Exposed or Sheltered


  • Chalk


  • Chalk


  • Chalk


  • MoistureWell-drained

  • SoilSand, Loam, Chalk

  • pHAcid, Alkaline, Neutral


  • 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 deep, well-drained, humus-rich soil ideally in full sun although they can tolerate some shade

Propagation Propagate by seed sown at 13°C in spring. Propagate by division in spring or autumn although they resent a lot of disturbance. Propagate by root cuttings from late autumn to early winter.

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

How to care

Pruning Cut back stems as the blooms fade to encourage further flower production

Pests Generally pest free

Diseases Generally disease free

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