Tansy (Tanacetum vulgare): Bitter Herb with Button Flowers

Tansy: The Golden Button Herb of Folklore and Caution

Tansy (Tanacetum vulgare) is a perennial herb with fern-like, aromatic leaves and dense, flat-topped clusters of bright yellow, button-like flowers. It has a long history in traditional medicine, cooking, and as an insect repellent, but contains toxic thujone and should be used with extreme caution.

Botanical Profile

Native to Europe and Asia, naturalized in North America. Grows 2–4 feet tall. The leaves are deeply divided, dark green, with a strong, camphoraceous scent. Flowers are rayless disks, like yellow buttons.

Historical Uses and Modern Cautions

• Traditional medicine: Vermifuge, digestive, emmenagogue. Toxic—can cause convulsions, liver damage, miscarriage.
• Insect repellent: Dried leaves in sachets for ants, moths, flies.
• Companion plant: Repels Colorado potato beetle, cucumber beetle.
• Dye: Flowers yield yellow; leaves yield green.

Grow in full sun, well-drained soil. Drought tolerant. Can be invasive; deadhead to prevent spread. Do not ingest. Wear gloves when handling. Hardy in USDA zones 4–8.