• 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

Clerodendrum trichotomum

harlequin glorybower

  • Other common names harlequin glorybower

  • Family Lamiaceae

  • Genus Clerodendrum can be deciduous or evergreen shrubs, trees or climbers, with simple, often unpleasantly scented, leaves and panicles of usually fragrant salver-shaped flowers with prominent stamens, followed by small berries

  • Details C. trichotomum is a deciduous large shrub or small tree with variable simple leaves, larger on young plants, the lower ones sometimes deeply two- ot three-lobed towards the apex. Fragrant flowers are produced from midsummer to autumn in long-stalked cymes from the axils of the upper leaves. Corolla white, in a reddish calyx, which deepens in colour as the fruits ripen in autumn. Berries bright blue at first, ultimately black, contrasting with the red calyces

  • Plant range Japan

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

  • Full Sun

  • Partial Shade

  • Aspect South-facing

  • Exposure Sheltered

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Sand

    Sand

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilChalk, Clay, Sand, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 4-8 metres

  • Ultimate spread 4-8 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation Grow in humus-rich moist soil in a sheltered position in sun or partial shade

Propagation Propagate by root cuttings or semi-hardwood cuttings

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

How to care

Pruning Pruning group 1

Pests Can get glasshouse red spider mite and glasshouse whitefly

Diseases Generally disease free

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