• 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

Aconitum napellus

monkshood

monkshood

© RHS

  • Other common names monkshood
    monk's hood

    Adam and Eve
    bear's foot
    common aconite
    common monk's cowl
    Cupid's cap
    dumbledore's delight
    Elijah's chariot
    flapdock
    grandmother's nightcap
    friar's cap
    garden monk's hood
    garden wolf's bane
    Helen flower
    Helen's flower
    helmet flower
    monk's cap
    pops
    soldier's cap
    Turk's cap
    Venus's chariot drawn by two doves

    see more
  • Family Ranunculaceae

  • Genus Aconitum can be herbaceous perennials or biennials with lobed leaves and racemes or panicles of showy, hooded flowers

  • Details A. napellus is an upright tuberous perennial to 1.5m tall, with deeply divided, dark green leaves and tall spires of violet-blue, hooded flowers in mid and late summer

  • Plant range Europe, Asia, America

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Toxicity All parts highly toxic if eaten

  • 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

  • Partial Shade

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

  • Exposure Sheltered

Soil

  • Chalk

    Clay

  • Chalk

    Loam

  • MoistureMoist but well-drained, Poorly-drained

  • SoilClay, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1-1.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Best grown in cool, moist, fertile in partial shade, but will tolerate most soils and full sun if soil is improved with well-rotted organic matter and mulched

Propagation Propagate by division between autumn and spring

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

How to care

Pruning Cut down plants in autumn

Pests Generally pest free

Diseases May suffer from powdery mildews

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