• 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

Oenanthe crocata

hemlock water dropwort

  • Other common names hemlock water dropwort
    balder root

    ban dock
    dead tongue
    hemlock dropwort
    hemlock wort
    water hemlock

    see more
  • Family Apiaceae

  • Genus Oenanthe are perennials with a preference for damp ground, marshes or water. Hollow stems are shiny and can grow up to 2m tall. Leaves are triangular, shiny and bright green and flowers are arranged in small white clusters. Brown, rugby-shaped seeds follow the flowers.

  • Details Hemlock water dropwort is an extremely poisonous, perennialplant. It forms elongated root tubers and has erect, hollow, grooved stems. Leaves are pinnate and flowerheads of white umbels, 5-10cm across, are borne in July and August

  • Plant range Europe, N. Africa


  • Foliage Deciduous

  • Habit Bushy

  • Toxicity Very poisonous to humans and livestock. Wear gloves and wash hands after handling

  • 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)




  • Full Sun

  • Aspect

  • Exposure


  • Clay


  • Loam


  • MoisturePoorly-drained

  • SoilClay, Loam

  • pH


  • Ultimate height 1-1.5 metres

  • Ultimate spread 1.5-2.5 metres

  • Time to ultimate height

How to grow

Cultivation Hemlock water dropwort grows naturally in damp meadows and near ditches and ponds

Propagation It will propagate by seed

Suggested planting locations and garden types

How to care

Pruning None required; for cutting down or removing plants, eye protection and gloves are advised

Pests Trouble-free

Diseases Trouble-free

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