• 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

Ptelea trifoliata

hop tree

  • Other common names hop tree
    shrubby trefoil

    stinking ash
    swamp devil's bit
    swamp dogwood
    wafer ash
    water ash
    wing seed

    see more
  • Family Rutaceae

  • Genus Ptelea are large, spreading deciduous shrubs with pungently scented, 3-foliate leaves and small yellow-green flowers in summer followed by attractive winged fruits

  • Details P. trifoliata is a large, deciduous shrub with dark green, tripartite leaves to 12cm long. Sprays of star-shaped, pale green flowers appear in summer, followed by bunches of flattened, winged seeds up to 2.5cm across. Leaves, flowers and bark are all aromatic

  • Plant range USA

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Fragrance Flower

  • 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 East-facing or West-facing

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained

  • SoilSand, Clay, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 4-8 metres

  • Ultimate spread 2.5-4 metres

  • Time to ultimate height 20-50 years

How to grow

Cultivation Grow in fertile well-drained soil in full or dappled sun. Suitable for shrub border or as a lawn specimen

Propagation Propagate by seed or semi-hardwood cuttings

Suggested planting locations and garden types Flower borders and beds Low Maintenance Cottage & Informal Garden

How to care

Pruning Pruning group 1

Pests Generally pest free

Diseases Generally disease free

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