• 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

Caryopteris × clandonensis 'Heavenly Blue'

bluebeard 'Heavenly Blue'

  • Other common names bluebeard 'Heavenly Blue'

  • Family Lamiaceae

  • Genus Caryopteris can be deciduous shrubs or perennials, with aromatic, simple leaves and small blue or white flowers in compact axillary clusters in late summer and autumn

  • Details 'Heavenly Blue' is a compact, upright shrub to 1m tall, with arching branches bearing toothed, grey-green leaves and clusters of small dark blue flowers in the leaf axils in late summer and early autumn

Characteristics

  • 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)

    H4

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained

  • SoilSand, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 1-1.5 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grow in moderately fertile, light, well-drained soil in full sun. Best positioned near a warm, sunny wall

Propagation Root softwood cuttings from spring to midsummer, semi-ripe cuttings from mid to late summer or hardwood cuttings from late autumn to midwinter

Suggested planting locations and garden types Flower borders and beds City & Courtyard Gardens Coastal Cottage & Informal Garden Mediterranean Climate Plants

How to care

Pruning Pruning group 6

Pests Capsid bug may cause leaf distortion

Diseases Generally disease free

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