• 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

Gymnocarpium dryopteris

oak fern

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
oak fern

© RHS

  • Other common names oak fern

  • Family Woodsiaceae

  • Genus Gymnocarpium are small deciduous ferns with a slender creeping rhizome, and much-divided, triangular to ovate fronds

  • Details G. dryopteris is a deciduous fern to 30cm tall, forming extensive colonies of bright green, triangular, 2 to 3-pinnate fronds 10-20cm long and wide

  • Plant range Temp. N. Hemisphere

Characteristics

  • Foliage Deciduous

  • Habit Mat forming

  • 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

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

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilSand, Loam

  • pHAcid, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grow in a neutral to acid, leafy, moist soil, enriched with garden compost, in deep shade

Propagation Sow spores at 15°C (59°F) when ripe or divide in spring

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

How to care

Pruning Cut back in autumn as fronds fade

Pests Generally trouble free

Diseases Generally trouble free

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