• 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

Ceratostigma plumbaginoides

hardy blue-flowered leadwort

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
  • Other common names hardy blue-flowered leadwort
    blue ceratostigma

  • Synonyms Ceratostigma larpentiae
    Plumbago larpentiae

  • Family Plumbaginaceae

  • Genus Ceratostigma can be evergreen or deciduous shrubs or herbaceous perennials, with simple leaves which usually colour well in autumn, and short terminal or axillary spikes of salver-shaped blue flowers in late summer and autumn

  • Details C. plumbaginoides is a low-growing herbaceous perennial with spreading roots, forming a mat of stems bearing oval leaves which turn red or purple in autumn. Clusters of rich blue flowers from late summer

  • Plant range W China

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

  • 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 East-facing

  • Exposure Sheltered

Soil

  • Chalk

    Loam

  • Chalk

    Sand

  • Chalk

    Chalk

  • Chalk

    Clay

  • MoistureMoist but well-drained, Well-drained

  • SoilLoam, Sand, Chalk, Clay

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in moderately fertile, moist but well-drained soil in full sun

Propagation Propagate by rooting softwood cuttings in spring or propagate by semi-hardwood cuttings in summer

Suggested planting locations and garden types Banks and Slopes Flower borders and beds Wall-side Borders City & Courtyard Gardens Cottage & Informal Garden Mediterranean Climate Plants

How to care

Pruning Cut back to ground level any shoots that get frost damaged

Pests Generally pest free

Diseases May be subject to powdery mildews

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