Plant · P-128

Common Tansy

Tanacetum vulgare

Common tansy is a hardy perennial with fern-like leaves and clusters of small yellow button flowers, historically strewn in cellars and churches and planted beside fruit trees and raspberries because its thujone content repels insects. The same chemical makes it a real insecticide and a folk vermifuge for intestinal worms, but the concentrated oil is dangerous - as little as half an ounce has killed an adult, and it should never be taken as a strong tea. It thrives in cool continental climates and stops well short of the hot, humid Deep South, where its native range simply ends.