• 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

Salix hastata 'Wehrhahnii' (m)

halberd willow 'Wehrhahnii'

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
  • Other common names halberd willow 'Wehrhahnii'

  • Family Salicaceae

  • Genus Salix are deciduous shrubs and trees of diverse habit, with simple leaves and tiny flowers in catkins, male and female usually on separate plants. Some are valued for their brightly coloured winter shoots, others for their foliage or showy male catkins

  • Details 'Wehrhahnii' is a slow-growing, small, spreading deciduous shrub with erect, purple-brown shoots bearing silvery-white male catkins, later yellow, followed by bright green leaves later dark, glaucous beneath

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)

    H6

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered or Exposed

Soil

  • Loam

    Loam

  • Clay

    Clay

  • Sand

    Sand

  • MoistureWell-drained, Moist but well-drained

  • SoilLoam, Clay, Sand

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1-1.5 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 20-50 years

How to grow

Cultivation A small, slow growing shrub for sun or partial shade

Propagation Propagate by softwood cuttings in early summer or hardwood cuttings in winter

Suggested planting locations and garden types Low Maintenance

How to care

Pruning Pruning group 1

Pests Can get aphids, caterpillars, leaf beetles and sawflies

Diseases May be subject to a rust

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