• 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

Streptocarpus 'Harlequin Blue' (PBR)

Cape primrose 'Harlequin Blue'

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 Cape primrose 'Harlequin Blue'

  • Family Gesneriaceae

  • Genus Streptocarpus can be annuals, perennials or subshrubs, with usually wrinkled, lance-shaped to rounded leaves and clusters of tubular to trumpet-shaped flowers with 5 spreading lobes, often borne throughout the year

  • Details 'Harlequin Blue' is a compact cultivar with short flower stems to 4.4cm and neat leaves. Flowers are distinctive with yellow lower lobes, which hold their colour well, soft blue upper lobes and very dark purple lines in the throat defining the extent of the two colours. Winner of the RHS Chelsea Flower Show Plant of the Year in 2010. Shortlisted for Chelsea Plant of the Centenary in 2013 for the decade 2003-2012

Characteristics

  • Foliage 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)

    H1C

Colour

Sunlight

  • Partial Shade

  • Aspect South-facing or East-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • MoistureMoist but well-drained

  • SoilSand, Clay, Chalk

  • 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 as a houseplant in loamless potting compost on an east or west-facing windowsill, or grow in a temperate or warm greenhouse in bright filtered light with shade from hot sun. Water sparingly as compost dries in winter and in the growing season water freely allowing compost to dry out between waterings; feed fortnightly with a high-potassium fertiliser. See Streptocarpus cultivation

Propagation Propagate by seed or leaf cuttings

Suggested planting locations and garden types Patio & Container Plants

How to care

Pruning No pruning required

Pests May be attacked by glasshouse leafhoppers, mealybugs, thrips, vine weevil and tarsonemid mite

Diseases Generally disease free

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