• 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

Quercus petraea

sessile oak

  • Other common names sessile oak
    durmast oak

  • Synonyms Quercus sessiliflora

  • Family Fagaceae

  • Genus Quercus can be deciduous or evergreen trees or shrubs, with entire, lobed or toothed leaves; flowers inconspicuous, followed by characteristic acorns; sometimes good autumn colour

  • Details Q. petraea is a large deciduous tree forming a broad, rounded crown, with rather leathery, dark green, lobed leaves to 15cm long, turning orange-brown in autumn. Inconspicuous yellowish flowers in catkins with the young leaves

  • Plant range Europe to W Russia

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)

    H7

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Exposed or Sheltered

Soil

  • Clay

    Clay

  • Chalk

    Chalk

  • Sand

    Sand

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilClay, Chalk, Sand, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height Higher than 12 metres

  • Ultimate spread wider than 8 metres

  • Time to ultimate height more than 50 years

How to grow

Cultivation Grows well in most deep, fertile soils

Propagation Propagate by seed, sown as soon as ripe, in a cold frame

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

How to care

Pruning pruning group 1

Pests Susceptible to aphids, caterpillars, leaf-mining moths and oak gall wasps

Diseases May be affected by powdery mildew

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