• 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

Arisaema consanguineum

© Catherine Lewis

  • Family Araceae

  • Genus Arisaema are mostly tuberous perennials usually with palmately lobed leaves, and distinctive tubular, hooded spathes within which the tiny true flowers are clustered at the base of the club-like or filamentous spadix, followed by a spike of red berries

  • Details A. consanguineum is a tall, tuberous perennial producing a single, umbrella-shaped leaf with 11-20 leaflets 20cm or more in length, on a stem up to a metre high. Below this, in summer, is the dark, purple-brown hooded spathe marked with fine green and white stripes. Striking, bright red berries appear in autumn

  • Plant range Himalaya Indochina


  • Foliage Deciduous

  • Habit Columnar/Upright

  • Toxicity Ingestion may cause severe discomfort

  • 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 South-facing or North-facing or West-facing or East-facing

  • Exposure Sheltered


  • Sand


  • Clay


  • Loam


  • MoistureMoist but well-drained

  • SoilSand, Clay, Loam

  • pHAcid, Neutral


  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in moist but well-drained, humus-rich soil in a cool site. Tubers must not dry out when dormant, and may need winter protection in colder areas

Propagation Propagate by seed, sowing them in containers in a cold frame in autumn or spring, or remove offsets in late summer

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

How to care

Pruning No pruning required

Pests Susceptible to slugs and vine weevil

Diseases Generally disease free

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