• 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

Adiantum raddianum

Delta maidenhair 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
Delta maidenhair fern

© RHS

  • Other common names Delta maidenhair fern

  • Synonyms Adiantum cuneatum
    Adiantum rubellum

  • Family Pteridaceae

  • Genus Adiantum can be deciduous or evergreen ferns with shiny black stalks bearing simple or more usually pinnately divided fronds, the segments fan-shaped, oblong or rounded, carrying spores under reflexed marginal flaps

  • Details A. raddianum is a tufted evergreen fern to 50cm, shortly rhizomatous, with smooth black stalks bearing triangular, 3-pinnate fronds composed of light green, rounded, lobed segments

  • Plant range Tropical America: W Indies

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)

    H1C

Colour

Sunlight

  • Partial Shade

  • Full Shade

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

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilLoam

  • pHAlkaline, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 1-2 years

How to grow

Cultivation Under glass, grow in moisture retentive well-drained soil, in bright indirect light in the summer and full light in the winter months

Propagation Sow spores as soon as ripe at a minimum of 21C (70F). Divide rhizomes in early spring

Suggested planting locations and garden types Low Maintenance Patio & Container Plants

How to care

Pruning Plant requires little pruning other than the removal of dead leaves

Pests Can be susceptible to scale insects

Diseases Generally trouble free

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