This section is from the book "The Gardener's Monthly And Horticulturist V21", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
There are many varieties of Eupatorium indigenous to America, but none rival the Eupatorium perfoliatum in its medicinal powers. The plant which gave name to the very extensive genus, of which the Bone-set is a species, are dedicated to Eupatos Mithridates, who is said to have used a species of the genus in medicine. Pursh describes twenty-seven as natives of North America; and others will be found extending beyond the tropics as far as Peru and Paraguay. The Bone-set, or Thoroughwort, is perhaps one of the most common of all the species inhabiting our country; it is found in meadows, on the margins of brooks and in damp woods. It is peculiar to North America, and easily distinguished from all other species. Many of the species are from five to seven feet high. The red-flowered species bloom with the white Bone-set, and decorate our autumnal landscapes with the profusion of their red and white flowers, and by the abundance in which they are everywhere met with. These plants are all plain except the E.coelestinum, the beautiful blue flowers of which have given rise to the appropriate specific name; it is never found much exceeding a foot in height, but occasionally in very rich ground, rather shaded from the sun, you will find a plant a foot and a half high.
Some months ago having seen the following description of a plant in Mr. Vick's catalogue, I supposed it was something entirely new: " A Mexican flower of a brush-like appearance, not showy in the garden, but prized by florists because it bears a great many flowers and keeps in bloom a long time, and is therefore desirable for bouquet-making. It is well to start the seeds under glass, and transplant to the flowering bed." This description was headed "Ageratum." I purchased the seed, and to my astonishment found myself the possessor of many young plants of the E.coelestinum. Nevertheless I scattered them around among my friends that we might all have this wonderful Mexican flower, and in March we had some rare heads of the "Ageratum," for even an old flower seems better when known by a new name.