Pyrethrum (Now classified as Chrysanthemum or Tanacetum plants), are hardy perennials. That said, they are frequently grown as hardy annuals in the garden.
They vary in height from 10 to 90 cm (4 to 36 inches). This makes them a versatile plant in the garden, and they are ideal for use in borders or edging.
Tanacetum coccineum - Painted Daisies by Hunda.
Pyrethrum plant species bloom from the middle of spring to summer. In bloom, they carry flowers reminiscent of daisies. The petals may be red, purple, pink or white.
The foliage is often fern-like.
Some common names for Pyrethrum (Tanacetum) plant genus members include Painted Daisy, Tansy, and Feverfew.
Pyrethrum cinerariifolium syn. Tanacetum cinerariifolium syn. Chrysanthemum cinerariifolium.
Pyrethrum cinerariifolium (Dalmatian pellitory), photograph by Koehler Images, Public domain; CC.
Pyrethrum coccineum syn. Tanacetum coccineum syn. Chrysanthemum coccineum,
Tanacetum coccineum (Painted Daisy ‘Robinson's Red’ Cultivar), picture by Leonora (Ellie) Enking; CC.
Common Names: Painted Daisy, Painted Lady (Coccineum), Tansy, Feverfew, Costmary, Alecost, Dalmatian Chrysanthemum, Persian Chrysanthemum.
Life Cycle: Hardy perennial commonly grown as a half hardy annual by gardeners.
Height: 4 to 60 inches (10 to 150 cm).
Native: Southwest Asia (Pyrethrum), Europe, Asia (Tanacetum).
Growing Region: Annuals: zones 1 to 10. Perennials: zones 8 to 10.
The seeds of Pyrethrum / Tanacetum plant species, such as Painted daisy and Feverfew, can be sown out in early autumn or early spring.
Once seeds have been sown, lightly cover the painted daisy seeds.
They like to grow in a sunny part of the garden that has good drainage. Ideally with a soil of pH 6 to 7.5.
The Pyrethrum plants should be spaced from 20 cm (8 inches, small varieties) to 60 cm (24 inches, large Pyrethrum / Tanacetum species) apart.
If growing indoors, first then sow the seeds about two months in advance.
The seeds should take about 3 to 9 weeks to germinate at 12 degrees centigrade (54°F).
Pyrethrum seedlings can be transplanted outdoors either in autumn, or before the last frost of spring.
Once growing, the pinching back of young Painted daisies or Feverfew plants at the tips will encourage branching.
Following the end of flowering, cut back the plants lightly and feed them. Plants should then produce a further bloom.
If you require more plants, then they can be propagated by division in the spring time.