• 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

Rubus fruticosus agg. 'Oregon Thornless' (B)

blackberry 'Oregon Thornless'

  • Other common names blackberry 'Oregon Thornless'

  • Family Rosaceae

  • Genus Rubus can be deciduous or evergreen shrubs, often scrambling with bristly or prickly stems bearing simple, lobed, palmate or pinnate leaves and 5-petalled flowers followed by juicy, sometimes edible fruits

  • Details 'Oregon Thornless' is a deciduous shrub with long, thornless canes to 2.5m in height and dark green lobed, pinnate leaves from spring to autumn. Bears 5-petalled white flowers in summer followed by dark blackberries in late summer

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • 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)

    H5

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered

Soil

  • Clay

    Clay

  • Loam

    Loam

  • Sand

    Sand

  • MoistureMoist but well-drained, Well-drained

  • SoilClay, Loam, Sand

  • pHNeutral

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 4-8 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Well-drained, neutral soil. Mulch with well-rotted compost or manure

Propagation Propagate by tip layering or from cuttings

Suggested planting locations and garden types Flower borders and beds Low Maintenance Wall-side Borders Banks and Slopes City & Courtyard Gardens Cottage & Informal Garden Patio & Container Plants

How to care

Pruning Cut out old canes following fruiting and tie in new canes

Pests Can get aphids, leafhoppers, raspberry beetle and gall mites

Diseases Good general resistance to disease

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