• 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

Sequoiadendron giganteum

giant redwood

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
  • Other common names giant redwood
    big tree

    wellingtonia
    giant sequoia
    mammoth tree
    Sierra redwood
    washingtonia

    see more
  • Synonyms Sequoia wellingtonia

  • Family Cupressaceae

  • Genus Sequoiadendron is a tall evergreen tree with soft, red-brown bark, flame-shaped when young, becoming more irregular with maturity. Short awl-shaped leaves are arranged spirally on the shoots, and ovoid cones become red-brown when mature

  • Details S. giganteum is a vigorous large evergreen tree forming a dense conical crown and thick, reddish-brown bark. Blue-green, awl-shaped leaves 6-12mm long arranged spirally round the shoots. Cone to 7cm, ovoid

  • Plant range California

Characteristics

  • Foliage Evergreen

  • 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 Exposed or Sheltered

Soil

  • Sand

    Sand

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained

  • SoilSand, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height Higher than 12 metres

  • Ultimate spread wider than 8 metres

  • Time to ultimate height 20-50 years

How to grow

Cultivation Grow in moderately fertile, well-drained soil in full sun or light dappled shade

Propagation Propagate by seed in containers in a cold frame in spring. Root softwood cuttings in summer or semi-ripe cuttings in late summer

Suggested planting locations and garden types Low Maintenance Architectural

How to care

Pruning No pruning required but will respond well to pruning back into older wood

Pests Generally pest free

Diseases Susceptible to honey fungus

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