• 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

Ceratonia siliqua


  • Other common names carob
    algoroba bean

    algorroba bean
    European locust tree
    locust bean
    St John's bread
    carob tree

    see more
  • Family Fabaceae

  • Genus Ceratonia are evergreen shrubs or small trees with wavy-margined, pinnate leaves. Erect racemes of tiny petal-less flowers are followed by conspicuous bean-like fruit

  • Details C. siliqua is a Mediterranean evergreen shrubby tree with thick brown bark and dark green, leathery, pinnate leaves. Tiny green-tinted red flowers in racemes 2-6cm long, during spring, are followed by edible black-brown leathery pods containing a sweet pulp

  • Plant range Medit., Arab., Som.


  • Foliage Evergreen

  • 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 Sheltered


  • Chalk


  • Loam


  • Sand


  • MoistureWell-drained

  • SoilChalk, Loam, Sand

  • pHAcid, Alkaline, Neutral


  • Ultimate height 8-12 metres

  • Ultimate spread 4-8 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation Grow in well-drained soil in full sun with shelter from a south or southwest facing wall

Propagation Propagate by seed soaked in water for 24 hours or propagate by semi-ripe cuttings with bottom heat

Suggested planting locations and garden types Drought Resistant Cottage & Informal Garden Mediterranean Climate Plants

How to care

Pruning Prune only to keep within bounds

Pests Generally trouble free

Diseases Generally trouble free

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