Common tansy was an important medicinal herb in Europe and was brought to the New World by American colonists and used as an ornamental plant. Today, it is considered invasive in North America.

Tansy is often classified as an herb, but it grows very easily and can be highly invasive. It is prohibited to be grown in Colorado, Minnesota, Montana, Wyoming and parts of Washington State.

Since this herb can be very invasive, it’s better to restrain it by planting it in containers. Including some tansy in your garden near a doorway will help deter insects from entering your home.