Tansy
Tanacetum vulgare
Botanical family: Asteraceae
Tanacetum vulgare, a robust perennial of banks and roadsides, recognisable by its bright-yellow gaiter-button flower heads and its camphorous smell. Historically used as a vermifuge and insecticide, it has been withdrawn from modern herbalism because of its toxicity.
Full sun
Any soil, even poor and dry
Low, tolerates drought; in moist soil it spreads fast
Very hardy (perennial, invasive through its rhizomes)
Overwinters in your zone
Role in permaculture
A perennial Asteraceae with divided foliage and a powerful camphorous scent, traditionally planted as an EDGING of the orchard or vegetable garden as a reputed repellent against aphids, Colorado potato beetles, and other pests, a use that belongs mostly to popular companion planting. Its corymbs of flat button-like yellow flowers are, on the other hand, a good resource for beneficial hoverflies and ladybirds. To be contained: its running rhizomes make it invasive.
Good companions
Traditional companion planting (benefit not demonstrated)
Insects attracted or useful
Seasons & availability
A hardy perennial sown in March and April, whose camphor-scented foliage returns in spring and flowers from July to September; the dried tops keep for the rest of the year.
Available: January, February, March, April, May, June, July, August, September, October, November, December.
Guidance for the oceanic / temperate climate; it may vary with your region, altitude, exposure and growing method.
Sources
- Plants For A Future, « Tanacetum vulgare » (pfaf.org/user/Plant.aspx?LatinName=Tanacetum+vulgare)
- Tela Botanica, « Tanacetum vulgare L. » (tela-botanica.org/bdtfx-nn-66761-description)
Nutritional & medicinal properties
For educational purposes. Not a substitute for medical advice. Effects depend on the form, the dose and personal context.
Precautions & contraindications
TOXIC plant: its essential oil is rich in thujone (especially beta-thujone), a neurotoxic compound. Internal use to be banned: tansy is reputed abortifacient, convulsant, and hepatotoxic. Formally not advised during pregnancy and breastfeeding, in young children, and in case of epilepsy. Like all Asteraceae, a risk of contact allergy. To be reserved for external use in the garden; for any other use, seek the advice of a health professional.
Family behaviour: Asteraceae
In general, Asteraceae are a family rich in flowers appreciated by pollinators and beneficials (pot marigold, yarrow, chamomile). It is very scattered, from the mildest lettuce to the allelopathic sunflower.
But this plant is an exception
A traditional companion of the apple guild, reputedly repellent, but not an all-purpose companion: very aromatic, rich in thujone and quick to spread, it belongs on the edge of trees or beds, not among delicate vegetables.
Understanding families means learning one rule per family rather than every pairing one by one. Learn more →
Species & varieties
The best-known species and varieties in France.
Common varieties
Voices of peoples
Paraphrases attributed to their documented sources. Never an invented quote.
European learned tradition reported by Maud Grieve, citing Dodoens and Ambrosius; the legend of Ganymede · Europe, Middle Ages, Renaissance; recorded in an encyclopaedic source of 1931
The name 'tansy' is said to derive from the Greek athanaton, 'immortal'. Maud Grieve reports two ancient explanations of this connection: according to Dodoens, because its dried flowers keep for a long time; according to Ambrosius, because the plant preserved bodies from corruption, tansy indeed serving for embalming and for keeping insects away from remains. A legend held that it had been given to Ganymede to make him immortal. In England, tansy cakes, bitter cakes made with the young leaves, were eaten at Easter, echoing the bitter herbs of the Jewish Passover.
M. Grieve, A Modern Herbal (1931), article « Tansy » (citant Dodoens et Ambrosius).
Solid documentation, since the source is named, but the content belongs to tradition: the derivation from athanaton and especially the legend of Ganymede are reported explanations, not certainties. The attested facts are the funerary and insect-repelling use of the plant and the custom of tansy cakes; the rest remains ancient interpretation. A plant toxic through its thujone: no internal use is advised.
Keep in mind
Its 'anti-aphid' repellent effect belongs to companion-planting tradition: reputed and sometimes observed, it is not solidly shown in the field, to be checked case by case.
A note on rigour: many companion pairings are gardening folklore; this note sums up what the sources say, where there are any.
Key takeaways
- • Prefers full sun exposure.
- • Ideal soil: any soil, even poor and dry.
- • Classic companion: Redcurrant.