Tanacetum annuum is a herbaceous perennial in the Asteraceae with a well-branched, rounded habit and deciduous foliage. It prefers full sun and suits well-drained loam or sandy soils across a wide pH range. Flowers appear from July to September. Native to parts of western Europe and north‑west Africa, it works well in cottage, wildlife and courtyard planting as well as mixed borders and beds.

Blue tansy (Tanacetum annuum) is a herbaceous perennial that flowers July to September and prefers full sun with well‑drained loam or sandy soils.

Tanacetum is a genus of about 160 species of flowering plants in the aster family, Asteraceae, native to many regions of the Northern Hemisphere. They are known commonly as tansies.

Tanacetum annuum

Blue tansy | Tanacetum annuum

Tanacetum cinerariifolium is a herbaceous perennial in the Asteraceae grown for daisy-like flowerheads that are white with yellow centres. Native to the western Balkans, including Albania, it produces blue-green deciduous foliage to about 0.5 m. Plants prefer full sun and a well-drained soil and will tolerate a broad range of soil types and pH. Flowering occurs July to September.

Pyrethrum (Tanacetum cinerariifolium) is a deciduous herbaceous perennial with blue-green leaves and daisy-like white flowers that bloom July to September.

Tanacetum cinerariifolium

Pyrethrum | Tanacetum cinerariifolium

Tanacetum herderi is a species in the tansy genus Tanacetum, a member of the Asteraceae. As with many Tanacetum species it produces composite flower heads with yellow disc florets and arises from forms typical of the genus. Flowering in the UK occurs from July to September. Leaves on Tanacetum species are typically alternate and often deeply lobed, and many plants in the genus carry a noticeable aroma.

Tanacetum herderi is a tansy species in the genus Tanacetum that flowers in the UK from July to September.