Dalmation Pellitory, Pyrethrum
Tanacetum cinerariifolium

Family: Asteraceae or Compositae

What it is like

Tanacetum cinerariifolium is a PERENNIAL growing to 0.5 m (1ft 8in) by 0.5 m (1ft 8in). See above for USDA hardiness. It is hardy to UK zone 6 and is not frost tender. It is in flower from July to September, and the seeds ripen from August to September. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees, flies. The plant is self-fertile. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils and can grow in very alkaline soils. It cannot grow in the shade. It prefers dry or moist soil. The plant can tolerate maritime exposure.

Height (m): 0.5

Where it is found

Rocky ground, usually by the seashore.

Europe - Dalmatia, Yugoslavia.

Conservation Status:

Countries/locations it is found in

How it is used

Food

Rating: 0

Medicine

Rating: 1

Dalmatian pellitory is not used medicinally, though research has shown that the flowers possess weak antibiotic activity. The flowers are the main source of the insecticide pyrethrum, which is toxic to insects but not to mammals. It has sometimes been used as a vermifuge in China.

Vermifuge: Expels and kills internal parasites.

Other

Rating:

The dried flower buds are the source of the insecticide 'Pyrethrum'. The pyrethrins are produced in the yellow disc florets. The highest pyrethrin content is from the flowers when they are in full bloom (1.22%) and lowest in the preceding period (0.71%). This insecticide also kills many beneficial insects, though it is relatively harmless to mammals. Another report says that it is non-toxic to mammals. It is best used in the evening so that it will have lost much of its virulence by the morning. Steep two handfuls of the dried powdered flowers in one litre of hot water for an hour. This mixture can be either pureed or strained and then used as a spray. Once dried, the flowers or the powder retain their insecticidal properties almost indefinitely. The growing plant can be used as an insect repellent in the garden. Effective against mosquitoes and ants.

Insecticide: Kills insects.

Repellent: Plants that are said to deter but not necessarily kill various mammals, birds, insects etc.

Industrial Crop: Pesticide: Many plants provide natural pesticides.

Management: Hay: Cut to the ground and harvested annually. Non-destructive management systems maintaining the soil organic carbon.

Minor Global Crop: These crops are already grown or traded around the world, but on a smaller scale than the global perennial staple and industrial crops, The annual value of a minor global crop is under $1 billion US. Examples include shea, carob, Brazil nuts and fibers such as ramie and sisal.

Industrial Crop: Pesticide: Many plants provide natural pesticides.

Management: Hay: Cut to the ground and harvested annually. Non-destructive management systems maintaining the soil organic carbon.

Minor Global Crop: These crops are already grown or traded around the world, but on a smaller scale than the global perennial staple and industrial crops, The annual value of a minor global crop is under $1 billion US. Examples include shea, carob, Brazil nuts and fibers such as ramie and sisal.

Carbon Farming: Plants that can be a critical part of the solution to climate problems. The Carbon Farming Solution - Eric Toensmeier.

How it is grown

Succeeds in an ordinary garden soil. Prefers a rich soil with plenty of humus. Prefers a pebbly, calcareous dry soil in a sunny position. When grown in moist climates the plants often die after flowering.Tolerates a pH in the range 5.2 to 7.5. Pyrethrum is widely cultivated as a source of an insecticide, the growing plant is also said to repel insects from plants growing nearby.

Propagating it: Seed - sow spring in a greenhouse. Only just cover the seed and do not allow the pot to dry out. Prick out the seedlings into individual pots once they are large enough to handle and grow them on in the greenhouse for their first winter. Plant out in late spring or early summer. Division in spring. Larger divisions can be planted out direct into their permanent positions. We have found that it is best to pot up smaller divisions and grow them on in light shade in a greenhouse or cold frame until they are growing away well. Plant them out in the summer or the following spring.

Best place to grow: Cultivated Beds;

Habit: Perennial

Hardiness: 5-9

Growth:

Soil: Light (sandy), medium, heavy (clay)

Shade: No shade

Moisture: Dry, moist

Things to keep in mind

Some people are highly allergic to this plant. Prolonged contact with the dried flowers can lead to allergic dermatitis, allergic rhinitis and asthma in humans.

Its other names

Local names

Synonyms

Chrysanthemum cinerariifolium. Pyrethrum cinerariifolium.