Comfrey

Symphytum officinale. Native to Europe but naturalized in North America. Extremely cold hardy perennial plant that is easy to grow. Cut down and let it wilt next to plants you want to prosper. It will grow right back and then you can cut it again. Flowers range from pink to purple. Plants reach about 2-3 ft tall. Don’t plant them in your vegetable garden because they sprout up from every root cutting. Some like to have them planted in orchards to increase fertility and to break up compacted earth. 

Largely pollinated by bumblebees.