• 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

Clethra alnifolia

bush pepper

  • Other common names bush pepper
    common white alder

    nana
    pink spire
    summer sweet
    sweet pepper bush

    see more
  • Family Clethraceae

  • Genus Clethra can be deciduous or evergreen trees or shrubs, sometimes with attractive bark, with simple leaves and small, fragrant, usually white, bell-shaped flowers in racemes or panicles

  • Details C.alnifolia, the sweet pepper bush is an erect, bushy, suckering shrub not usually exceeding 2m. The fresh green leaves are simple, obovate, neatly serrrate, sometimes turning yellow in autumn. Near-white scented flowers are abundantly produced, in erect terminal racemes, in summer. Pink selections are available

  • Plant range E N America

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Fragrance Flower

  • 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

  • Partial Shade

  • Full Shade

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

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Clay

    Clay

  • Sand

    Sand

  • MoistureMoist but well-drained

  • SoilLoam, Clay, Sand

  • pHAcid

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 1.5-2.5 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grow in fertile humus-rich moist but well-drained acid soil, best in part or dappled shade

Propagation Propagate by seed in spring or autumn; propagate by softwood cuttings in early summer

Suggested planting locations and garden types Low Maintenance Cottage & Informal Garden

How to care

Pruning Pruning group 1; remove some of the old wood from the base in winter, leaving the strongest suckers as replacement growth

Pests Generally trouble free

Diseases Generally trouble free

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