Oenanthe crocata
hemlock water dropwort
Hemlock water dropwort is an extremely poisonous, perennial plant. 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
Other common names
balder rootban dock
see moredead tongue
hemlock dropwort
hemlock wort
water hemlock
Size
Ultimate height
1–1.5 metresTime to ultimate height
2–5 yearsUltimate spread
1.5–2.5 metresGrowing conditions
Moisture
Poorly–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | White | Green | ||
| Autumn | Green | |||
| Winter |
Position
- Full sun
Aspect
East–facing or South–facing or West–facing
Exposure
Sheltered Hardiness
H7Botanical details
- Family
- Apiaceae
- Native to GB / Ireland
- Yes
- Foliage
- Deciduous
- Habit
- Clump forming
- Potentially harmful
- TOXIC if eaten. Wear gloves and other protective equipment when handling TOXIC to pets if eaten (dogs) - see the HTA guide to potentially harmful plants for further information and useful contact numbers
- 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.
- Name status
Correct
- Plant range
- Europe, N. Africa
How to grow
Cultivation
Hemlock water dropwort grows naturally in damp meadows and near ditches and ponds and can become a nuisance if left unchecked. For a list of alterntive plant to use in ponds and streams, please go to our advice profile on pond plants
Propagation
Propagate by seed
Suggested planting locations and garden types
- Wildlife gardens
Pruning
No pruning required
Pests
Generally pest-free
Diseases
Generally disease-free
Get involved
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