Comfrey is a tall, easy to care for perennial plant, Comfrey plants shoot up quickly, early in the season, and can easily reach heights of around five feet. The lower leaves are equally large, somewhat dwarfing the hanging clusters of flowers at the top of the plant. The form and size of the plants might make you think it is a shrub, but it will die back to the ground in the winter, and it does not get woody. Once comfrey is established it will take care of itself. Each year the plant will get a little larger, and the root system will get denser. It is very hard to get rid of an established comfrey plant. Comfrey can live several decades before it begins to decline. Because of its deep taproot, comfrey is drought tolerant. However regular watering will keep it growing strong and blooming.