• 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

Zanthoxylum simulans

Sichuan pepper

  • Other common names Sichuan pepper
    Chinese pepper

  • Synonyms Zanthoxylum bungei var. inermis

  • Family Rutaceae

  • Genus Zanthoxylum are broadly rounded to upright, spiny, deciduous or evergreen trees and shrubs. They have aromatic bark and leaves. Sprays of small green or yellow-green flowers appear in spring or summer, followed by small fruits that split to reveal seeds attached by short threads

  • Details a bushy, spiny, medium to large deciduous shrub or small tree. The ash-like leaves are up to 8cm long with up to 11 broad leaflets. Flat-topped sprays of small, yellow-green flowers are produced in early summer, followed by open clusters of small, red fruits that split open to reveal black seeds. Leaves, bark and fruit are all aromatic

  • Plant range China, Taiwan


  • Foliage Deciduous

  • Habit Bushy

  • Fragrance Bark

  • 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 or East-facing

  • Exposure Sheltered


  • Chalk


  • Loam


  • Sand


  • MoistureWell-drained

  • SoilChalk, Loam, Sand

  • pHAcid, Alkaline, Neutral


  • Ultimate height 2.5-4 metres

  • Ultimate spread 2.5-4 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation Grow in fertile, well-drained soil in full sun or light, dappled shade

Propagation Propagate by seed, or root semi-ripe cuttings in midsummer with bottom heat, or take root cuttings in late winter

Suggested planting locations and garden types Low Maintenance Flower borders and beds Cottage & Informal Garden Patio & Container Plants City & Courtyard Gardens

How to care

Pruning Pruning group 1

Pests Generally trouble free

Diseases Generally trouble free

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