The common tansy (Tanacetum vulgare) is a perennial with emerald-green, fern-like leaves and bright yellow button shapes flowers. Tansy is often classified as an herb, but it grows very easily and can be highly invasive plant.
What Is a Tansy?
The tansy is a perennial plant, native to Europe, that is known for its bright, yellow, button-shaped flowers. It grows to about two to four feet tall and up to 18 inches wide. It's a gorgeous, low-maintenance plant... except for its tendency to self-sow like there's no tomorrow. And if that wasn't enough, it also spreads by underground rhizomes. So that's something to keep in mind if you're considering adding tansy to your garden: it's likely to stick around for a while.
Tansy is hardy in Zones 3 to 8, and usually blooms in July and August.
Where to Plant Tansy
Tansy thrives in full sun to partial shade, as well as fertile, well-drained soil. That being said, it'll grow pretty much anywhere, though it will bloom less the more shade it gets. Tansy is also drought-tolerant, and, once established, rarely needs to be watered.
Most nurseries don't sell tansy, due to its reputation as an invasive plant or weed. So you'll have to start your tansy from seed. Sow the seed directly in the garden in early spring and keep them well-watered until they're established.
Tansy Pests and Diseases
Tansy doesn't suffer from any pest or disease problems. There isn't much that harms this plant, which is another reason it has a tendency to become invasive.
To keep tansy from seeding all over your garden, remove spent flowers as soon as possible, before they set seed. This will go a long way toward keeping the plant in check. You'll also want to check the area regularly for any plants that are sprouting from the rhizomes, and either dig them out or transplant them to another area.
Is Tansy an Herb or Weed?
Tansy was considered a usable herb in ancient times, but in the modern world, most consider it to be a weed. In fact, it is considered a nuisance thanks to its invasive tendencies to crowd out natural indigenous plant life. The main issue with tansy is its ability to self-sow, which it does enthusiastically! But if you can keep that tendency in check and be mindful of where you're planting it, there's no reason not to grow this cheerful, useful, low-maintenance plant.
Identifying Common Tansy
Common tansy is easy to identify. Its yellow button flowers grow in clusters on straight stems that can range from three to four feet tall. The flower diameter is between ¼" to ½".
How to Combat Invasive Tansy
Tansy grows wild and can take over a field. You can find it growing along the road, in pastures/meadows or even in yards. The control techniques include:
- Hand-pulling or digging up clumps is a tedious method. Rhizomes can easily be left behind underneath the soil and resume spreading.
- Larger infestations will respond to weed killer. Always use gloves to avoid contact toxicity.
- You can also mow the plants, especially during the budding stage.
Tansy shouldn't be ingested since it can be toxic. In fact, medieval midwifes administered tansy tea to women desiring an abortion. Tansy is poisonous to humans and most pets, especially cats.
Interesting Facts About Tansy
Tansy has a long, and storied history. If you enjoy learning the story behind the plants you grow in your garden or find in your area, you might enjoy knowing these interesting facts about the tansy flower.
Tansy Flower Meaning
Tansy generally symbolizes health, resistance, and protection. As you'll see from the facts below, there's a good reason for that!
Brought to America
Tansy was introduced to America by European settlers when it was still used for medicinal and religious purposes, such as Easter. The button flowers were often used as decorative landscaping plants and quickly became naturalized.
Natural Insect Repellent
Tansy is a natural insect repellent. It will repel flies as well as mosquitos. Since it is so highly invasive, you can use it as an insect repellent by placing plants in a container.
Origin of the Word "Tansy"
The word tansy comes from the Greek word athanatos, which means "immortal," and referred to the long life cycle of the plant. It's ironic, since tansy can be toxic.
Tansy was once an esteemed herb among ancient Greeks and retained its status for centuries. The tansy's fern-like leaves were ideal as bookmarks for Bibles. In fact, this kind of bookmarker was called Bible Leaf. The herb scent, often compared to mint, would release whenever the Bible was opened. The Greeks preserved bodies for burial by wrapping the corpse with tansy leaves.
During medieval times, tansy was the go-to herb for ridding the body of worms. It was also used as a digestive aid. Additionally, meat was covered with tansy leaves to repel insects. Do not follow those practices today due to the toxicity of the plant. Tansy was one of the herbs strewn on medieval castle floors as well as homes, so the scent would be released whenever it was walked on.
Tansy is used in Ayurvedic medicine for a wide range of ailments and conditions. For example, it can be added to distilled water to cleanse the skin and used to kill lice, scabies, and fleas.
Some gardeners use tansy plants to repel insects. If you decide to plant tansy for this reason or around a patio, it's best to plant in pots or containers, so you can better control it.