People often grow tansy for its golden, bright, vibrant flowers, and by looking at this photograph, you can probably see why. It’s symbolic of summertime and happiness. Even though tansy has previously been historically used for flavoring, it contains a toxic essential oil that may kill a human. If it doesn’t kill you, it will cause liver and brain damage, and at the very least, an allergic reaction to those who touch the flower. There’s a reason we don’t recommend growing these beautiful flowers in your backyard. The risk isn’t worth the reward (Growveg).