• 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

Lycium barbarum

Duke of Argyll's tea tree

  • Other common names Duke of Argyll's tea tree
    Chinese box thorn

    Barbary box thorn
    Barbary wolfberry
    common matrimony vine
    vicar's tea party
    Tibetan goji berry

    see more
  • Family Solanaceae

  • Genus Lycium can be deciduous or evergreen shrubs, sometimes scrambling, with simple entire leaves and small funnel-shaped flowers followed by red berries

  • Details L. barbarum is a scrambling deciduous shrub to 3m tall, with sparsely spiny stems bearing narrow, dull green leaves and small dingy purple flowers in late spring and summer, followed by orange-red berries

  • Plant range Europe to China

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)

    H5

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Sheltered or Exposed

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureMoist but well-drained, Well-drained

  • SoilSand, Clay, Chalk, Loam

  • pH

Size

  • Ultimate height 2.5-4 metres

  • Ultimate spread 1-1.5 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grow in moderately fertile, well-drained soil in full sun. Can be grown as a hedge

Propagation Propagate by seed in containers outdoors in autumn. Take hardwood cuttings in winter or softwood cuttings in early summer

Suggested planting locations and garden types Banks and Slopes Flower borders and beds Hedging & Screens Coastal Cottage & Informal Garden

How to care

Pruning pruning group 1 or pruning group 11 in winter or early summer. Cut back hedges hard in spring or trim in early summer

Pests Generally trouble free

Diseases Can suffer from powdery mildew

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