• 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

Carpinus caroliniana

American hornbeam

  • Other common names American hornbeam
    blue beech

    ironwood
    water beech

    see more
  • Synonyms Carpinus americana

  • Family Betulaceae

  • Genus Carpinus are deciduous shrubs and trees with attractive foliage and hop-like fruit clusters in late summer and autumn

  • Details

    C. caroliniana is a small, deciduous tree to around 10m tall with branches that droop at the tips and fluted, grey bark. The bright green leaves are ovate, serrated and prominently veined and turn shades of orange, yellow and red in autumn. Green catkins borne in spring are followed by fruiting clusters around 7cm long in autumn

  • Plant range E N America

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • 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)

    H7

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilSand, Clay, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 8-12 metres

  • Ultimate spread wider than 8 metres

  • Time to ultimate height more than 50 years

How to grow

Cultivation Grow in a fertile, well-drained soil in full sun or partial shade

Propagation Propagate by seed, softwood cuttings or by grafting

Suggested planting locations and garden types Low Maintenance

How to care

Pruning Pruning group 1

Pests Generally trouble free

Diseases Generally trouble free

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