Comfrey is a shrub that grows in parts of Europe, Asia, and North America. It can grow up to 5 feet tall. It produces clusters of purple, blue, and white flowers, and it’s famous for its long, slender leaves and black-skinned roots. The root and leaves of the comfrey plant have been used in traditional medicine in many parts of the world. In Japan, the plant has been harvested and used as a traditional treatment for over 2,000 years. It was originally called “knit bone” and people used it to treat: muscle sprains bruises burns, joint inflammation. Europeans have also used comfrey to treat inflammatory conditions, such as arthritis and gout. Some traditional healers have also used it to treat diarrhea and other stomach ailments. The roots of leaves of the comfrey plant contain chemical substances called allantoin and rosmarinic acid. Allantoin boosts the growth of new skin cells, while rosmarinic acid helps relieve pain and inflammation. Extracts are still made from the roots and leaves and turned into ointments, creams, or salves. These solutions typically have a comfrey content of 5 to 20 percent. While comfrey is well-known for its health benefits, it also poses some risks. It contains compounds that can harm your liver. It may also be carcinogenic. As a result, many countries have banned the sale of oral comfrey preparations. Many experts also advise against using topical comfrey on open wounds. But comfrey may be acceptable for short-term use on your skin and closed wounds. You can purchase topical comfrey preparations from many health stores. Talk to your doctor before using them to learn more about the potential benefits and risks.
Comfrey is a remarkable plant. Soak the leaves to make a powerful (and free!) liquid fertilizer. Add the leaves to the soil, or your compost heap, to enrich them. Use the dead leaves to make leaf mold as nutritious potting compost. Comfrey leaves contain a balance of the vital nutrients nitrogen, phosphorus, and potassium – all of which are needed by growing plants. Comfrey leaves contain up to three times more potassium than farmyard manure.  It helps the plant to flower, seed, and fruit.