• 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

Lobelia erinus Purple Star = 'Wespurstar' (PBR)

trailing lobelia [Purple Star]

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 lobelia [Purple Star]

© RHS

  • Other common names trailing lobelia [Purple Star]

  • Synonyms Lobelia 'Purple Star'

  • Family Campanulaceae

  • Genus Lobelia can be annuals, perennials or shrubs, with simple leaves and showy 2-lipped flowers that may be solitary or in racemes or panicles

  • Details Purple Star is a low-growing plant, with stems to 27cm long, small, narrow, olive green leaves and a trailing habit. The two-lipped flowers, 2cm across, are vivid purple, produced abundantly in summer and autumn

Characteristics

  • Foliage Deciduous

  • Habit Mat 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)

    H2

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Clay

    Clay

  • Chalk

    Chalk

  • Sand

    Sand

  • MoistureMoist but well-drained

  • SoilLoam, Clay, Chalk, Sand

  • pHAcid, Neutral, Alkaline

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 1-2 years

How to grow

Cultivation Grow in moist but well-drained soil in full sun or light shade. Ideal for bedding schemes or in containers especially in partial shade. Avoiding drought stress will prolong flowering, as will liquid feeding

Propagation Propagate by seed

Suggested planting locations and garden types Flower borders and beds Garden Edging City & Courtyard Gardens Coastal Cottage & Informal Garden Patio & Container Plants

How to care

Pruning Remove after flowering ceases in autumn

Pests Generally pest free

Diseases Generally disease free

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