• 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

Cotoneaster sternianus

Stern's cotoneaster

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 Stern's cotoneaster

  • Synonyms Cotoneaster franchetii var. sternianus

  • Family Rosaceae

  • Genus Cotoneaster can be deciduous or evergreen shrubs or small trees, with simple, entire leaves and clusters of small white or pink flowers in spring and summer, followed by showy red, purple or black berries

  • Details C. sternianus is a large, semi-evergreen shrub with small leaves grey-green above, white-felted beneath. Flowers small, pinkish-white; berries relatively large, bright red, abundant, in small clusters

  • Plant range Burma, China (NW Yunnan)

Characteristics

  • Foliage Semi-evergreen

  • Habit Bushy

  • Toxicity Fruit may cause mild stomach upset if ingested

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

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • Clay

    Clay

  • Chalk

    Chalk

  • MoistureWell-drained

  • SoilSand, Loam, Clay, Chalk

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 2.5-4 metres

  • Ultimate spread 2.5-4 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation Will tolerate dry situations but may need some shelter from cold, drying winds in colder climes

Propagation Propagate by seed sown as soon as ripe in autumn in containers in a cold frame or by semi-hardwood cuttings in late summer

Suggested planting locations and garden types Cut Flowers Flower borders and beds Cottage & Informal Garden

How to care

Pruning Pruning group 8 or pruning group 13 for wall-trained specimens

Pests May be attacked by scale insects and woolly aphids

Diseases May be subject to fireblight

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