• 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

Chaenomeles × superba 'Knap Hill Scarlet'

Japanese quince 'Knap Hill Scarlet'

Japanese quince 'Knap Hill Scarlet'

© RHS 2003

  • Other common names Japanese quince 'Knap Hill Scarlet'

  • Family Rosaceae

  • Genus Chaenomeles are deciduous, usually spiny shrubs with simple leaves and cup-shaped, 5-petalled flowers, solitary or clustered, in spring, followed by edible often fragrant green or yellow fruits

  • Details 'Knap Hill Scarlet' is a spreading small deciduous shrub, with glossy obovate leaves to 5cm in length. Flowers to 4cm in width, bright orange-scarlet. Fruits yellow, apple-shaped, fragrant when ripe

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Fragrance Fruit

  • 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)

    H6

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Exposed or Sheltered

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Sand

    Sand

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilChalk, Clay, Sand, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1-1.5 metres

  • Ultimate spread 1.5-2.5 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation Grow in well-drained soil in sun or partial shade

Propagation Propagate by semi-hardwood cuttings

Suggested planting locations and garden types Low Maintenance Wall-side Borders Cottage & Informal Garden

How to care

Pruning Pruning group 2

Pests Can get brown scale and aphids

Diseases Fireblight may be a problem

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