Tansy

Tansy grows like a weed along roadsides in many areas of North America, so if you're curious enough to desire a look at the plant, some of you may easily be able to do so. If this invasive grows in your own landscape, at least deadhead the flowers to keep them from going to seed.

By late summer, you might wish to cut tansy to the ground, as the appearance of its fern-like foliage may start to suffer from the heat. If you cut it back early enough, a new batch of foliage will emerge in autumn (in warm climates, re-blooming may actually result).

Tansy flowers have naturalized (along roadsides, for example) in parts of North America, where the plant is widely considered to be invasive.

The publication of this article should not be considered an endorsement for growing tansy flowers; rather, the information here is provided for research purposes and for those who already have tansy growing in their yards.

If tansy flowers are already growing on your property and you're curious about what organic weed control measures you can take to eradicate this invasive, I do not have good news for you. Tansy is difficult to eradicate without chemicals. Tansy plants spread not only by reseeding, but also via underground rhizomes. One way to check the spread of their rhizomes is by using bamboo barriers. Some people mow tansy down to weaken it and keep it from producing seed, but this approach won't eradicate the plants.

While tansy plants has now fallen out of favor in some quarters due to its poisonous potential and invasive tendencies, it was nonetheless once a much admired herb.

Tansy plant's common name derives from the Greek athanatos, meaning immortality (perhaps because tansy was used in ancient times for embalming). In Greek mythology, Zeus was said to have made Ganymede immortal by giving the latter tansy on Mount Olympus.

Tansy was an important medicinal and culinary herb in Europe for centuries. "In medieval times, tansy was used for a variety of ailments," says Stephen Byrnes. "Its most well-known use was for expelling intestinal worms, particularly in children. Children infected by these parasites would have a cup of tansy tea in the morning, and another at night."

Given tansy's pedigree in the European tradition, it is not surprising that tansy was soon brought to the New World by the American colonists and granted a position of prominence there in the garden. "Use of common tansy led the governor of Massachusetts to list common tansy as a necessary plant for colonial herb gardens in the 1600s," according to Montana State University. "This led to widespread cultivation of the plant and its inevitable escape into fields and roadsides." That escape has culminated in tansy's being listed by watchdog groups as one of the worst invasive plants in North America.