From The Buffalo Seed Company:
 
Bring in the pollinators, make a unique cup of tea, or crumble flowers in a salad. This beautiful plant grows 3 to 5 feet tall and is a great way to connect your production system into the natural ecology of the area—you will see pollinators like never before. This species is perennial, but cannot withstand an extremely cold Midwest winter. Seedlings comes up early in the season with purple leaves, transitions to green, and finally returns to purple late in the season. Plant a large stand and experience the scent of mint and licorice fragrance.