# Herb bennet (Geum urbanum)

*Wood avens; *herba benedicta*, the blessed herb*

**Known today as.** *Geum urbanum*, of the rose family, with a root that smells of cloves.

Kind: Plant

## What was it used for?

The clove-scented root, for fluxes, fevers, and a weak stomach; laid among linen, and steeped in ale.

## What does modern science say?

The root contains eugenol, the chief scent of cloves, and tannins; no clinical evidence for its uses.

## Pharmacognosy and toxicology

- **eugenol**: freed from the glycoside gein, the clove scent
- **gein**: 
- **tannins**: 20–30 per cent of the root

**Mechanism.** A strong astringent with a clove-oil antiseptic: the eugenol is antibacterial and the tannins tighten, which is why it was a gargle and kept moths from linen.

**Dose.** Safe at tea doses.

**Standing.** No monograph; in the German tradition for diarrhoea and mouth inflammation.

## What lore surrounds it?

The blessed herb kept evil away: the *Hortus sanitatis* of 1491 says that where the root is in the house, the devil can do nothing, and flies from it; its three-lobed leaf and five petals were read as the Trinity and the five wounds.

## What did the older authorities say?

**Its name.** *Herba benedicta*, the blessed herb, became “bennet” in English.

## Sources

- Grieve, M. (1931). *A Modern Herbal*, “Avens.”
- *Hortus sanitatis* (Mainz, 1491).
- Wichtl, M. (2004). *Herbal Drugs and Phytopharmaceuticals*, 3rd ed., “Gei urbani rhizoma.”

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*Herb bennet.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-09-30. The Thinking Press. https://thethinkingpress.org/materia-medica/herb-bennet

Historical description, not medical advice.