Mercurialis annua
annual mercury
A annual with an upright, branching habit, growing up to 50cm tall. It has green, lance-shaped leaves, finely serrated up to 6cm long and arranged in opposite pairs along smooth stems. From July to October, it produces small, greenish, petal-less flowers, with male flowers in clusters and female flowers appearing singly or in small groups
Other common names
baron's mercuryboy's mercury
see moreFrench mercury
girl's mercury
herb mercury
bresychen-y-cŵn flynyddol
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
1 yearUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drained, Poorly–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Green | Green | ||
| Autumn | Green | |||
| Winter |
Position
- Full shade
- Full sun
- Partial shade
Aspect
East–facing or North–facing or South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H5Botanical details
- Family
- Euphorbiaceae
- Native to GB / Ireland
- Yes
- Foliage
- Deciduous
- Habit
- Matforming
- Potentially harmful
- Pets: Harmful if eaten. For further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
- Name status
Correct
- Plant range
- Europe to W Asia
How to grow
Cultivation
Thrives in disturbed soils in gardens, farmland, roadsides, and waste ground, as well as urban areas, woodland edges, hedgerows, and some coastal regions
Propagation
Self-seeds freely
Suggested planting locations and garden types
- Wildlife gardens
Pruning
No pruning required
Pests
Generally pest-free
Diseases
Generally disease-free
Get involved
The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.