Botanical atlas

Tansy

Tanacetum vulgare

Tansy has a long and tangled history in European folk practice. Its bitter, camphor-scented leaves were strewn on floors and packed into linens to keep flies and moths away, and sprigs were once tucked into meat and burial shrouds for the same reason. Cooks in medieval and Renaissance England baked the young leaves into bitter Lenten cakes, believed to cleanse the body after the long winter fast. Herbalists also turned to tansy as a vermifuge to expel intestinal worms and, more perilously, as an emmenagogue meant to bring on delayed menstruation, a use that carried real and sometimes fatal risk. Because of this history, tansy is remembered today more as a garden and folklore plant than as a kitchen or medicine cabinet staple.

Safety.

Tansy is toxic and should not be ingested. Its essential oil and leaves contain thujone, a compound that in even modest amounts can cause seizures, liver and kidney damage, and other serious poisoning symptoms; the essential oil in particular has caused fatalities. Tansy has historically been used as an abortifacient, and this use has caused documented deaths and severe organ damage, so it is never safe for use during pregnancy, and it should also be avoided while breastfeeding and kept away from children and pets. Handling the fresh plant can cause contact dermatitis in sensitive individuals, and anyone with ragweed or related plant allergies should be cautious even around the dried flowers. This entry is offered for historical, botanical, and garden interest only, not as a guide to use. Please talk with a qualified healthcare provider before considering any herbal preparation, and treat tansy as a plant to admire and grow rather than to consume.