• 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

Epimedium grandiflorum 'Nanum'

dwarf large-flowered barrenwort

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
dwarf large-flowered barrenwort

© RHS 1993

  • Other common names dwarf large-flowered barrenwort

  • Family Berberidaceae

  • Genus Epimedium are rhizomatous perennials with evergreen or deciduous, ternately or pinnately divided leaves, and open sprays of small, bowl-shaped flowers, often with prominent spurs, in mid to late spring

  • Details 'Nanum' is a compact deciduous perennial to 20cm, forming a clump of divided leaves, bronze-tinged when young. Long-spurred pale purple flowers 3cm in width are borne in open sprays

Characteristics

  • 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)

    H5

Colour

Sunlight

  • Partial Shade

  • Aspect East-facing or West-facing

  • Exposure Sheltered

Soil

  • Clay

    Clay

  • Loam

    Loam

  • Sand

    Sand

  • MoistureMoist but well-drained

  • SoilClay, Loam, Sand

  • pHAcid, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grow in fertile, moist but well-drained, humus-rich soil in partial shade; shelter from cold, dry winds

Propagation Propagate by division in autumn or after flowering

Suggested planting locations and garden types Flower borders and beds Garden Edging Low Maintenance Underplanting of Roses and Shrubs Cottage & Informal Garden

How to care

Pruning Cut back old foliage in late winter or early spring for the best display of new foliage and flowers

Pests May be attacked by vine weevil

Diseases May be subject to a virus

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