• 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

Campanula poscharskyana 'Stella'

trailing bellflower 'Stella'

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
trailing bellflower 'Stella'

© RHS

  • Other common names trailing bellflower 'Stella'

  • Family Campanulaceae

  • Genus Campanula may be annuals, herbaceous or evergreen perennials, with bell or star-shaped, often blue, flowers in late spring or summer

  • Details 'Stella' is a tufted perennial with rounded basal leaves and spreading stems bearing loose racemes of starry, light violet-blue flowers 2.5cm in width

Characteristics

  • Foliage Semi-evergreen

  • 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)

    H5

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Aspect South-facing or East-facing

  • Exposure Exposed

Soil

  • Chalk

    Chalk

  • Loam

    Loam

  • Sand

    Sand

  • Clay

    Clay

  • MoistureMoist but well-drained

  • SoilChalk, Loam, Sand, Clay

  • pHAlkaline, Neutral, Acid

Size

  • Ultimate height Up to 10 cm

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in moist but well-drained soil in sun or partial shade; can be invasive as spreads by underground runners

Propagation Propagate by division in spring or autumn

Suggested planting locations and garden types Flower borders and beds Garden Edging Banks and Slopes Ground Cover City & Courtyard Gardens Cottage & Informal Garden Gravel Garden Patio & Container Plants Rock Garden

How to care

Pruning Cut back after flowering to maintain compact shape

Pests May be attacked by slugs and snails

Diseases May be subject to powdery mildews

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