• 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

Eriophorum angustifolium

common cotton grass

  • Other common names common cotton grass

  • Synonyms Eriophorum polystachion
    Scirpus angustifolius

  • Family Cyperaceae

  • Genus Eriophorum are evergreen rhizomatous perennials forming spreading clumps of tufted, linear leaves, with solitary or clustered, ovoid black-scaled, silky-haired flower-heads, followed by conspicuous cottony white fruiting heads

  • Details E. angustifolium is a vigorously spreading perennial forming many tufts of dark green, linear leaves, with white-hairy flower-heads in summer

  • Plant range Subarctic & Temp N Hemis.


  • Foliage Evergreen

  • 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

  • Aspect South-facing or West-facing

  • Exposure Sheltered or Exposed


  • Sand


  • Clay


  • Loam


  • MoisturePoorly-drained

  • SoilSand, Clay, Loam

  • pHAcid


  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 1-1.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in acid soil at pond margins, in full sun, in water up to 5cm deep

Propagation Propagate by division in spring

Suggested planting locations and garden types Low Maintenance Wildflower meadow

How to care

Pruning Deadhead regularly

Pests Generally pest free

Diseases May be affected by powdery mildews

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