• 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

Cyathea cooperi

Cooper's tree 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
  • Other common names Cooper's tree fern
    Australian tree fern

    lacy tree fern
    scaly tree fern

    see more
  • Synonyms Alsophila cooperi
    Cyathea cooperi

  • Family Cyatheaceae

  • Genus Cyathea are evergreen tree ferns, but may be deciduous in cold areas, the rhizome forming an erect trunk clothed in fibrous roots, bearing large, pinnately-divided fronds with scaly stalks, in a rosette at the top

  • Details C. cooperi is a fast-growing tree fern reaching 5m in ideal conditions, with a slender stem and mid-green fronds up to 4m long.

  • Plant range Australia

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)

    H2

Colour

Sunlight

  • Partial Shade

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

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Sand

    Sand

  • MoistureMoist but well-drained

  • SoilLoam, Sand

  • pHAcid, Neutral

Size

  • Ultimate height 2.5-4 metres

  • Ultimate spread 2.5-4 metres

  • Time to ultimate height 20-50 years

How to grow

Cultivation In areas prone to frost, grow in a container under glass with a minimum winter temperature of 10?C. The plant may be placed outside during the summer in a sheltered and partially-shaded spot. It requires a moist but well-drained, humus-rich soil; in hot, dry summers water the stem as well as the soil, but avoid watering the crown in winter. Apply liquid fertiliser monthly during the growing season. Will grow without winter protection only in milder areas

Propagation Propagate by sowing spores as soon as ripe

Suggested planting locations and garden types Flower borders and beds Architectural City & Courtyard Gardens Coastal Cottage & Informal Garden

How to care

Pruning Dead or damaged fronds may be removed as necessary

Pests Generally pest free outdoors

Diseases Generally disease free

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