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Dog's mercury

Mercurialis perennis

Also called Dog Mercury

Dog's mercury
Photo: Unknown author, Public domain

Dog's mercury is a low-growing, spreading perennial woodland plant native to Europe and parts of the Mediterranean and western Asia, forming dense carpets under trees and hedges. It thrives in cool, shaded, moist woodland conditions and is best left to naturalise in wild or woodland gardens.

Family
Euphorbiaceae (Spurge family)
Grows as
Perennial
Light
Shade, Part shade
Water
Keep soil moist in spring and summer; it tolerates normal rainfall well once established.
Soil
Rich, moist, humus-rich woodland soil, neutral to alkaline preferred.
Temperature
Hardy to around -20 °C; prefers cool conditions.
How easy
Easy
Safety
Toxic: The whole plant is poisonous when raw; the juice is emetic and purgative, and drying or heating destroys much of the toxicity.
Native range
Europe, Medit. to N. Iran
Climate
temperate

About

Mercurialis perennis, commonly known as dog's mercury, is a poisonous woodland plant found in much of Europe as well as in Algeria, Iran, Turkey, and the Caucasus, but almost absent from Ireland, Orkney and Shetland. A member of the spurge family (Euphorbiaceae), it is a herbaceous, downy perennial with erect stems bearing simple, serrate leaves. The dioecious inflorescences are green, bearing inconspicuous flowers from February to April. It characteristically forms dense, extensive carpets on the floor of woodlands and beneath hedgerows.

Uses

The dog's mercury is poisonous by itself but with a thorough drying/heating, one is able to destroy its poisonous quality. The juice of the plant is emetic, ophthalmic and purgative. It can be used externally to treat menstrual pain, ear, and eye problems, warts, and sores. A lotion can be made from the plant for antiseptic external dressing due to its ability to soften and moisturise the skin.

Other Mercurialis plants

Annual mercury

Text excerpted from the Wikipedia article Mercurialis perennis by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.

The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.

Life form, climate and native range: World Checklist of Vascular Plants, Royal Botanic Gardens, Kew (CC BY 3.0), reformatted; see Plants of the World Online.

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