• 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 'William Stearn'

barrenwort 'William Stearn'

barrenwort 'William Stearn'

© Dorling Kindersley Ltd

  • Other common names barrenwort 'William Stearn'

  • 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 'William Stearn' is a clump-forming rhizomatous perennial 18-30cm high, with evergreen leaves divided into heart-shaped leaflets which emerge mottled and splashed with dark red and mature to green, and very dark red flowers with pale pink spurs tipped with yellow, in spring; Epimedium leaves may be used for their nests by leaf-cutting bees

Characteristics

  • 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)

    H6

Colour

Sunlight

  • Partial Shade

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

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • MoistureMoist but well-drained

  • SoilLoam, Sand, Clay, Chalk

  • pHNeutral, Acid, Alkaline

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in fertile, humus-rich, moist but well-drained soil in partial shade, with shelter from cold, drying winds; where frosts are prolonged or severe, spread an organic mulch such as leaf mould or composted bark to protect plants over winter

Propagation Propagate by division in autumn or after flowering; or by root cuttings of rhizomes, kept under glass in winter, and planted out after all danger of frost has passed

Suggested planting locations and garden types Ground Cover Underplanting of Roses and Shrubs Garden Edging Flower borders and beds Banks and Slopes Low Maintenance Cottage & Informal Garden City & Courtyard Gardens

How to care

Pruning No pruning required, but cutting back in late winter or early spring, before flower spikes form, will improve appearance

Pests May be affected by vine weevil

Diseases May be affected by mosaic virus diseases and fungal leaf spots

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