• 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

Liquidambar styraciflua 'Corky'

sweet gum 'Corky'

  • Other common names sweet gum 'Corky'

  • Family Hamamelidaceae

  • Genus Liquidambar are deciduous trees grown for their alternate, maple-like leaves which take on brilliant and long-lasting autumn colour; flowers and fruits are inconspicuous

  • Details 'Corky' is an upright, narrowly pyramidal, deciduous, small to medium-sized tree up to 12m tall with deeply lobed, glossy green leaves that turn crimson red in autumn. Very pronounced wing-like, corky projections on the stems and bark are a feature of established trees. Inconspicuous greenish flowers may be followed by burr-like fruit, 2-4cm across, that stay on the tree through winter

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)

    H6

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered or Exposed

Soil

  • Loam

    Loam

  • Clay

    Clay

  • Sand

    Sand

  • MoistureWell-drained, Moist but well-drained

  • SoilLoam, Clay, Sand

  • pHAcid, Neutral

Size

  • Ultimate height 8-12 metres

  • Ultimate spread 4-8 metres

  • Time to ultimate height more than 50 years

How to grow

Cultivation Grow in lime-free soil in sun or partial shade

Propagation Propagate by semi-hardwood cuttings

Suggested planting locations and garden types Low Maintenance Cottage & Informal Garden

How to care

Pruning Pruning group 1

Pests Generally trouble free

Diseases Generally trouble free

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