• 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

Ribes sanguineum 'Koja'

flowering currant 'Koja'

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
flowering currant 'Koja'

© Dorling Kindersley Ltd

  • Other common names flowering currant 'Koja'

  • Family Grossulariaceae

  • Genus Ribes can be deciduous or evergreen shrubs, sometimes spiny, with simple, usually palmately lobed leaves and small tubular or bell-shaped, solitary or racemose flowers borne in spring or summer, followed by juicy, sometimes edible berries

  • Details 'Koja' is a deciduous shrub reaching about 2m high with blackcurrant-scented, lobed leaves and hanging clusters of deep red-pink flowers in mid- to late spring, sometimes followed by black berries

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Fragrance Leaf

  • 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

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

  • Exposure Sheltered or Exposed

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 1.5-2.5 metres

  • Ultimate spread 1-1.5 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Easy to grow in moderately fertile well-drained soil in full sun. Useful for informal hedging

Propagation Propagate by hardwood cuttings in winter

Suggested planting locations and garden types Flower borders and beds Hedging & Screens City & Courtyard Gardens Coastal Cottage & Informal Garden

How to care

Pruning Pruning group 2 or Pruning group 13 if wall-trained, in late summer; trim hedges after flowering

Pests Aphids may be a problem

Diseases May be affected by a leaf spot, powdery mildews, honey fungus and coral spot

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