• 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




  • 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
    grandmother's nightcap
    friar's cap
    garden monk's hood
    garden wolf's bane
    Helen flower
    Helen's flower
    helmet flower
    monk's cap
    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


  • Foliage Deciduous

  • Habit Bushy

  • Toxicity All parts are 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)




  • Partial Shade

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

  • Exposure Sheltered


  • Chalk


  • Chalk


  • MoistureMoist but well-drained, Poorly-drained

  • SoilClay, Loam

  • pHAcid, Alkaline, Neutral


  • 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 in autumn or late winter to maintain vigour but plants may be slow to re-establish. Use protective gloves when handling any part of the plant

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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