• 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
  • Synonyms Lycium europaeum
    Lycium halimifolium

  • 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


  • 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


  • Chalk


  • Clay


  • Loam


  • Sand


  • MoistureMoist but well-drained, Well-drained

  • SoilChalk, Clay, Loam, Sand

  • pH


  • 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 Hedging & Screens Banks and Slopes Flower borders and beds Cottage & Informal Garden Coastal

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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