• 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

Acer negundo

box elder

  • Other common names box elder
    ashleaf maple

    ash-leaved maple

    see more
  • Family Sapindaceae

  • Genus Acer can be deciduous trees or large shrubs with paired, often palmately-lobed leaves and small flowers followed by characteristic winged fruits. Many have fine autumn colour, and some have ornamental stems

  • Details A. negundo is a vigorous deciduous tree with pinnate leaves on green young shoots, male and female flowers on separate plants; yellow autumn colour

  • Plant range N America, Guatemala, Mexico

Characteristics

  • Foliage Deciduous

  • 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

  • Loam

    Loam

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • MoistureWell-drained, Moist but well-drained

  • SoilLoam, Sand, Clay, Chalk

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height Higher than 12 metres

  • Ultimate spread wider than 8 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation Grow in a moist but well-drained soil

Propagation Propagate by seed or grafting

Suggested planting locations and garden types Low Maintenance Cottage & Informal Garden Architectural City & Courtyard Gardens Patio & Container Plants

How to care

Pruning Pruning group 1

Pests Aphids and horse chestnut scale may be a problem

Diseases Verticillium wilt may be a problem

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