• 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

Cornus controversa

giant dogwood

  • Other common names giant dogwood

  • Family Cornaceae

  • Genus Cornus can be deciduous shrubs or trees, or creeping, woody-based perennials, some with brightly coloured young stems. Tiny flowers are borne in dense clusters, sometimes with showy bracts. Many have fine autumn colour

  • Details C. controversa is a deciduous tree to 15m tall, with a distinctive tiered branching pattern and glossy, elliptic leaves often turning purple in autumn; flat clusters of small white flowers may be followed by small, blue-black berries

  • Plant range Him., China, Japan

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)

    H5

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

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilSand, Clay, Loam

  • pHAcid, Neutral

Size

  • Ultimate height Higher than 12 metres

  • Ultimate spread wider than 8 metres

  • Time to ultimate height more than 50 years

How to grow

Cultivation Grow in well-drained soil in sun or partial shade

Propagation Propagate by grafting

Suggested planting locations and garden types Flower borders and beds Architectural

How to care

Pruning Pruning group 1

Pests Generally pest free but can get horse chestnut scale

Diseases Generally disease free

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