• 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 horizontalis

wall spray

  • Other common names wall spray
    rock spray

    wall cotoneaster

    see more
  • Synonyms Cotoneaster acuminata var. prostrata

  • 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. horizontalis is a spreading dwarf deciduous shrub to 2m in width, with distinctive, flat, regularly-branched sprays of foliage with small glossy leaves that turn orange and red in autumn. Pink-tinged flowers and red berries

  • Plant range W China

Characteristics

  • Foliage Deciduous

  • Habit Trailing

  • Toxicity Fruit may cause mild stomach upset if ingested. Wear gloves and wash hands after handling

  • 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)

    H7

Colour

Sunlight

  • Full Sun

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

  • Exposure Exposed or Sheltered

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Loam

    Loam

  • Sand

    Sand

  • MoistureWell-drained

  • SoilChalk, Clay, Loam, Sand

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 1-1.5 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation This plant is listed on Schedule 9 of the UK Wildlife & Countryside Act as an invasive non-native species. While this does not prevent it from being sold in the UK, or from being grown in gardens, the RHS encourages those that do grow it to take great care with managing it and with disposing of unwanted material. The RHS also encourages gardeners to find alternative plants to grow to those listed on Schedule 9. For suggested alternative plants see the Plantlife/RHS guide: Gardening without harmful invasive plants

Propagation Propagate by seed or semi-hardwood cuttings

Suggested planting locations and garden types Hedging & Screens Low Maintenance Banks and Slopes Drought Resistant Ground Cover Cottage & Informal Garden

How to care

Pruning Pruning group 1

Pests Can get brown scale, Cotoneaster webber moth, aphids and woolly aphid

Diseases May suffer from fireblight

Did you find the information you were looking for?

RHS members can get exclusive individual advice from the RHS Gardening Advice team.

Join the RHS now

Get involved

The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.