The kidneys are paired retroperitoneal structures that are normally located between the transverse processes of T12-L3 vertebrae, with the left kidney typically somewhat more superior in position than the right. The upper poles are normally oriented more medially and posteriorly than the lower poles.
Growing Comfrey in Pots. Comfrey will grow in pots (at least 3 gallon), containers such as plastic tubs, or 5-gallon plastic buckets but they do better when not grown in a pot. They have deep roots so prefer growing in the garden where they get more nutrients. The containers need drainage holes in the bottom. Add fertilizer to the potting soil.
Story at-a-glance 1  +. Comfrey oil is extracted from comfrey (Symphytum officinale), a perennial herb of the Boraginaceae family with a black, turnip-like root and large, hairy broad leaves bearings small, bell-shaped flowers. 2  The plant has found widespread use in folk and herbal medicine, acting as a healing agent.omfrey, while considered an important herbal medicine, is controversial due to its toxic components which led to the banning of oral products. The dilemma is how to weigh the virtues of Comfrey oil while considering the safety concerns that surround it.