• 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

Cryptomeria japonica 'Sekkan-sugi'

Japanese cedar 'Sekkan-sugi'

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
Japanese cedar 'Sekkan-sugi'

© RHS

  • Other common names Japanese cedar 'Sekkan-sugi'

  • Family Cupressaceae

  • Genus Cryptomeria are large evergreen trees with attractive red-brown bark and dense foliage consisting of short awl-shaped leaves arranged spirally around the branchlets; cones are spherical

  • Details 'Sekkan-sugi' is a small, conical evergreen tree, to 10m tall, with semi-pendulous branches. The soft, awl-shaped leaves are a pale creamy-yellow colour when young, maturing to a dark green with yellow tints in winter

Characteristics

  • Foliage Evergreen

  • Habit Columnar/Upright

  • 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

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilSand, Clay, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 8-12 metres

  • Ultimate spread 2.5-4 metres

  • Time to ultimate height 20-50 years

How to grow

Cultivation Grows in any moist but well-drained soil in a sheltered position

Propagation Propagate by semi-hardwood cuttings

Suggested planting locations and garden types Low Maintenance Architectural City & Courtyard Gardens

How to care

Pruning None required

Pests Generally trouble free

Diseases Generally trouble free

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