If you are looking for a colorful herb that looks wonderful in the herb and vegetable garden along with your landscaping, then tansy is for you. While this plant can mature to be two to four feet in height and one foot in width, this herbaceous perennial creates unique texture and color that will surprise you. The leaves are fern like while the flowers look like bright yellow buttons. As beautiful as this plant is, the other unique feature that if posses is the smell. Tansy produces a strong aroma that keeps pests away from the garden space, which makes it a must in any organic garden. But do not worry; those kept away are ones that do not consume nectar. This means that the pollinator will still visit your garden.
When it comes to growing tansy, you have two choices. Tansy can be started by seed or you can simply get a start from a friend through division. For information though, seed propagation will be described.
Tansy is a perennial in USDA Plant Hardiness Zones 4 through 8. While it is hardy in these areas, you still need to wait until after your local frost free date has passed before direct seeding. If you want to get a jump on the season, start your seeds indoors six to eight weeks prior to your local frost free date. Once you have the date, clean and sterilize your pot.
Fill the container with soil and water in until moisture comes out the bottom. Next, sprinkle seeds on top and cover with ¼ inch of soil. Place your planted pot in a clear bag and seal. Put your pot in a location by which it can receive indirect sunlight. In 7 to 10 days, your seeds will germinate.
Once you see signs of seed germination, remove the container from the bag and place on a sunny windowsill. Monitor the soil moisture and add water when needed. When the tansy seedlings have several leaves, transplant them into individual pots. Go through the hardening off process two weeks prior to your local frost free date. Once that is done, plant your tansy in the garden making sure that you space them six inches apart in a sunny location.
While tansy is not very picky about the soil, the more average to poor it is the better.
Divide tansy in the early spring.
As wonderful as this plant is there is one issue. Tansy can become an unwanted “weed.” This is due to its self-seeding nature and the spreading through rhizomes. To reduce the self-seeding, make sure to deadhead often.