• 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

Ilex verticillata

winterberry

winterberry

© RHS

  • Other common names winterberry
    black alder

    feverbark
    swamp winterberry

    see more
  • Family Aquifoliaceae

  • Genus Ilex can be deciduous or evergreen shrubs and trees with often spiny leaves, small white flowers (male and female usually on separate plants) and, on female plants, showy berries in autumn

  • Details I. verticillata is a dense, suckering, deciduous shrub, growing to 2m tall, with bright green, oval to lance-shaped leaves with serrated margins. Insignificant greenish-white flowers, borne in spring, are followed on female plants by masses of long-lasting, glossy red berries

  • Plant range E. North America

Characteristics

  • Foliage Deciduous

  • Habit Suckering

  • 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

  • Full Sun

  • Partial Shade

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

  • Exposure Exposed or Sheltered

Soil

  • Clay

    Clay

  • Loam

    Loam

  • MoisturePoorly-drained, Moist but well-drained

  • SoilClay, Loam

  • pHAcid, Neutral

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 1-1.5 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Prefers a moist, acidic, organic loamy soil and has a good tolerance for poorly-drained soils so useful for boggy areas

Propagation Propagate by seed or by softwood cuttings

Suggested planting locations and garden types Banks and Slopes Hedging & Screens Low Maintenance Cottage & Informal Garden

How to care

Pruning Pruning group 1

Pests Generally trouble free

Diseases Generally trouble free

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