• 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 carmichaelii (Arendsii Group) 'Arendsii'

monk's hood 'Arendsii'

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 monk's hood 'Arendsii'

  • Family Ranunculaceae

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

  • Details 'Arendsii' forms a clump of erect stems bearing deeply divided leaves and spires of rich lavender-blue flowers in early and mid-autumn

Characteristics

  • 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)

    H7

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Clay

    Clay

  • MoistureMoist but well-drained

  • SoilLoam, Clay

  • 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 moisture retentive fertile soil in partial shade but sun and most soils are tolerated. Staking may be necessary

Propagation Divide every third year in autumn or late winter to maintain vigour, although plants can be slow to re-establish. Use gloves when handling plants as all parts are highly toxic

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

How to care

Pruning Tall stems can be pruned down later in autumn when flowering is finished

Pests Aphids may be troublesome

Diseases Fungal stem rot and Verticillium wilt may occasionally be troublesome

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