• 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

Mahonia aquifolium

Oregon grape

  • Other common names Oregon grape
    mountain grape

    holly-leaved barberry
    Rocky Mountain grape

    see more
  • Synonyms Mahonia piperiana
    Berberis aquifolium

  • Family Berberidaceae

  • Genus Mahonia are evergreen shrubs with leathery, pinnate leaves which are often spine-toothed, and clustered racemes of sometimes fragrant yellow flowers, sometimes followed by black or purple berries

  • Details M. aquifoliumis a vigorous, low, spreading, evergreen shrub with glossy green,slightly pricklyleaves becoming purplish in winter. Large clusters of yellow flowers appear in spring, followed by black berries

  • Plant range W North America

Characteristics

  • Foliage Evergreen

  • 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 Shade

  • Partial Shade

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

  • Exposure Exposed or Sheltered

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Loam

    Loam

  • Sand

    Sand

  • MoistureMoist but well-drained, Well-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 5-10 years

How to grow

Cultivation Tolerates a very wide range of growing conditions but does best in humus-rich, moist but well-drained soil in semi-shade

Propagation Propagate by seed and semi-hardwood cuttings

Suggested planting locations and garden types Banks and Slopes Low Maintenance Drought Resistant Ground Cover Wildlife Gardens

How to care

Pruning Pruning group 8

Pests Generally pest free

Diseases A rust and powdery mildews may be a problem

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