• 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

× Cuprocyparis leylandii 'Castlewellan'

Leyland cypress 'Castlewellan'

  • Other common names Leyland cypress 'Castlewellan'

  • Synonyms × Cupressocyparis leylandii 'Galway Gold'
    × Cuprocyparis leylandii 'Galway Gold'

    × Cupressocyparis 'Castlewellan Gold'
    × Cupressocyparis leylandii 'Castlewellan'
    × Cupressocyparis leylandii 'Castlewellan Gold'

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  • Family Cupressaceae

  • Genus Cuprocyparis are large, very fast-growing evergreen trees of narrowly conical or columnar habit, with tiny scale-like leaves in dense sprays, and small spherical cones

  • Details 'Castlewellan' is a vigorous columnar evergreen conifer to 25m or more, with flat sprays of golden-yellow foliage, sometimes tinged bronze


  • Foliage Evergreen

  • Habit Columnar/Upright

  • Toxicity Foliage may cause skin irritation. Wear gloves and other protective equipment when handling

  • 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)




  • Full Sun

  • Partial Shade

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

  • Exposure Exposed or Sheltered


  • Chalk


  • Clay


  • Loam


  • Sand


  • MoistureWell-drained

  • SoilChalk, Clay, Loam, Sand

  • pHAcid, Alkaline, Neutral


  • Ultimate height Higher than 12 metres

  • Ultimate spread 2.5-4 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation Grow in well-drained soil in full sun or part shade. Suitable for hedging but requires regular trimming. Fast growing with the potential to become a nuisance

Propagation Propagate by semi-hardwood cuttings

Suggested planting locations and garden types Hedging & Screens Architectural

How to care

Pruning No pruning required, but can be trimmed and shaped as required as long as cuts are confined to young green shoots. Old wood will not resprout. Trim hedges two or three times in the growing season

Pests May be affected by conifer aphids and scale insects

Diseases May be subject to a canker and honey fungus; see Conifers: brown patches

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