From “Pyrethrum” in Flowers and Their Histories by Alice M. Coats:
“Pyrethrum roseum (syn. Chrysanthemum coccineum), parent of the hardy border pyrethrums so valuable for cutting, was introduced from the Caucasus at a date variously reported as 1804, 1818 or 1826. At first it was not very greatly esteemed, and indeed the flower as it was portrayed in Maund’s Botanic Garden in 1830 is not very attractive; its pink florets are short in relation to the disc and the whole flower rather overwhelmed by its abundant leafage. Some years later, however, a large rose form was raised by M. Themisterre, a Belgian florist, and was sent by him to Mr. John Salter of Hammersmith, under whose care the centre of the flower was gradually filled and the double form evolved. The varieties raised by this nurseryman were reported to be ‘very numerous, various and beautiful and to include shades of white, pink, red and crimson, singly or in combination’….
“From the early days of its cultivation it was known that this plant was a principal ingredient in the manufacture of Persian insect-powder; and its near relation, P. cinerariifolia, was used for the same purpose in Dalmatia. The powder is produced from the flower-heads, which are cut just as they are about to open, carefully dried, and pulverized; and ‘Pyrethrum-powder’ as an insecticide has become of increasing importance in the present century. Pyrethrums are grown for this purpose in Kenya, and were considered a crop of the first priority during the last war, for their value in the control of insect pests and the prevention of typhus and other insect-spread diseases….
“The Greek name comes from pyr, meaning fire, and was originally given to a plant with a hot, biting root, which the early botanists identified with another nearly-related plant, now called Anthemis pyrethrum or Pellitory of Spain. This is rather a tender species, grown here before 1570, but subsequently lost, and reintroduced by Philip Miller in 1732, when he raised some plants from seeds he found sticking to a bunch of Malaga raisins. The root of this plant was formerly used as a cure for toothache; but it is no longer in cultivation as a garden-flower.”
Hello!
This is the third of four posts with photos that I took in late November and the first two weeks of December, of Aster family members that I identified as Tanacetum coccineum. The first post is Technicolor Tanacetum (1 of 4), and the second post is Technicolor Tanacetum (2 of 4).
In the previous two posts for this series, I showed photos of these Painted Daisies where the flowers featured a single dominant color, or the flower petals showed shades or blends of single colors. To illustrate that more precisely, here’s a photo from the second post, next to one from this post.
Both photos show the plants producing more than one flower on a single stem, but those in the photo on the left are quite different from those on the right. On the left, we see the petals all contain shades of the same colors (purples through magenta); whereas the plant on the right produced flowers with distinct colors: one yellow, two orange, one pink, and even — barely visible behind the middle pink flower — one that has purple petals. This variation would not have been a natural accident; it would have been produced intentionally by breeders seeking to develop a variant with these color capabilities. Even those plants that have only produced two flowers (like the first three in my galleries below) show the same capability: they produce one orange and one yellow flower, rather than just varying shades of orange or yellow throughout their petals.
With a breeding history stretching back thousands of years, these color variations depart significantly from the colors present in historically native plants in the Tanacetum and Chrysanthemum genera — which would have been yellow, white, or red (like those in my first post), depending on whether they originated from Asia or the Caucasus region. Blending colors in single flowers, or creating plants capable of producing flowers each with two or three distinct colors, would have occurred through genetic manipulation of hundreds of plant generations where the presence of certain color traits was selectively emphasized.
The plant we now call Tanacetum coccineum (previously known as Chrysanthemum coccineum and as Pyrethrum roseum) has had a long botanical history through Asian and Western cultures, with Chinese chrysanthemum breeding known to have occurred as far back as 1500 BC. As I noted in the first post in this series, there’s a separation reflecting how differently Tanacetum coccineum was represented in botanical history: it was likely not distinguished from chrysanthemums in ancient Chinese or Japanese culture, and wasn’t separated from the Chrysanthemum genus until the twentieth century, when the names Chrysanthemum coccineum and Pyrethrum roseum began to fade from botanical literature. The quotation at the top of this post — from Alice Coats’ Flowers and Their Histories, published in the mid-twentieth century while these name changes were in flux — partially addresses the name ambiguities (which we’re used to by now, right?). While its names vary, however, there is something common to every accounting of Tanacetum that I’ve seen so far: the use of its chemical components as insecticides, or as the basis for manufactured insecticides, embedded throughout the entire 3000-year period where humans have documented the plant’s history. We’ll take a look at the significance — and uniqueness — of those historical threads in the fourth post in this series.
Thanks for reading and taking a look!
Beautiful