• 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

Pterocarya fraxinifolia

Caucasian wingnut

  • Other common names Caucasian wingnut
    Caucasian walnut

  • Synonyms Pterocarya pterocarpa
    Pterocarya caucasica

  • Family Juglandaceae

  • Genus Pterocarya are tall deciduous trees with large pinnate leaves and tiny flowers in pendulous catkins, followed by spikes of winged fruits

  • Details P. fraxinifolia is a vigorous, broadly spreading deciduous tree with large pinnate leaves and small green flowers in drooping racemes to 50cm long, followed by winged fruits

  • Plant range E Turkey, N Iran, Caucasus


  • 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

  • Aspect West-facing or South-facing

  • Exposure Exposed or Sheltered


  • Clay


  • Loam


  • Sand


  • MoistureMoist but well-drained

  • SoilClay, Loam, Sand

  • pHAcid, Alkaline, Neutral


  • 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 deep, fertile, moist but well-drained soil in full sun

Propagation Propagate by seed in containers outdoors in autumn. Remove rooted suckers in autumn

Suggested planting locations and garden types Architectural Cottage & Informal Garden

How to care

Pruning Pruning group 1; remove unwanted suckers and seedlings as they appear

Pests Generally trouble free

Diseases Generally trouble free

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

Get involved

The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.