• 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

Liquidambar styraciflua

sweet gum

sweet gum


  • Other common names sweet gum
    American red gum

    American sweet gum
    copalm balsam
    red gum
    satin walnut

    see more
  • Family Hamamelidaceae

  • Genus Liquidambar are deciduous trees grown for their alternate, maple-like leaves which take on brilliant and long-lasting autumn colour; flowers and fruits are inconspicuous

  • Details L. styraciflua is a deciduous tree to 20m tall, broadly conical in outline, with rather glossy, maple-like, 5 to 7-lobed leaves which turn to shades of orange, crimson and purple in autumn

  • Plant range Eastern USA


  • 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)




  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered or Exposed


  • Chalk


  • Chalk


  • Chalk


  • MoistureWell-drained, Moist but well-drained

  • SoilLoam, Clay, Sand

  • pHAcid, Neutral


  • 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 lime-free soil in sun or partial shade. Suitable for woodlands

Propagation Propagate by semi-hardwood cuttings

Suggested planting locations and garden types Flower borders and beds

How to care

Pruning Pruning group 1

Pests Generally pest free

Diseases Generally disease free

Advertise here

Did you find the information you were looking for?

RHS members can get exclusive individual advice from the RHS Gardening Advice team.

Join the RHS now