An indigenous European plant, comfrey grows in all temperate regions of the world, including western Asia, North America, and Australia. Comfrey thrives in moist, marshy places. Comfrey can be grown from seed in spring or by root division in autumn, and the leaves and flowering tops are harvested in summer. The root is unearthed in autumn.
Comfrey is used in folk medicine in the form of an externally applied poultice for healing wounds. Comfrey is also taken internally as a tea or blended plant extract (so-called green drink) to heal stomach ulcers and to act as a "blood purifier". Less restrained advocates preach its virtue in treating cuts and wounds, burns, respiratory ailments of the lungs and bronchial passages, and ulcers of the bowels, stomach, liver, and gallbladder. It is even said to facilitate the healing of broken bones, but this almost certainly comes from a misunderstanding of one of the common names of the plant, knitbone. It may have once been used to reduce the swelling and inflammation around a broken bone, but not to heal the bone itself.
Whatever healing properties comfrey may have are probably caused by its content of allantoin, an agent that promotes cell proliferation. Quantities of tannin and mucilage are also present. The underground parts contain 0.6 to 0.7 percent allantoin and 4 to 6.5 percent tannin; the leaves are poorer in allantoin, containing only about 0.3 percent, but richer in tannin, 8 to 9 percent. Large amounts of mucilage are present in both roots and leaves. Much has been made of the vitamin B12 content of comfrey, but compared to the more customary natural source, liver, the concentration in the plant is not especially high.
Although comfrey has been one of the most common herbs sold to the American public over the past thirty years, there is reason to believe that using comfrey internally is definitely hazardous to the health. All comfrey species investigated have been found to contain hepatotoxic pyrrolizidine alkaloids (PAs), but the literature on the subject is confused due to a glaring lack of attention to proper botanical identification of the various Symphytum species studied. Common comfrey contains principally 7-acetylintermedine and 7-acetylly-copsamine in addition to their unacetylated precursors and symphytine. It does not contain high levels of echimidine, probably the most toxic comfrey PA. Echimidine has been identified, along with symphytine and six other PAs, in Russian comfrey. Russian comfrey was heavily promoted in the back-to-the-land movement, and most of the comfrey cultivated in home gardens is the Russian hybrid. The former alkaloid is also present in prickly comfrey. Comfrey root contains about ten times the concentration of PAs found in the leaves.
Past uses - Comfrey has been used to treat stomach ulcers, irritable bowel syndrome, and a range of respiratory conditions, including bronchitis and pleurisy. Injuries - Comfrey's ability to promote the healing of bruises, sprains, fractures, and broken bones has been known for thousands of years. Comfrey encourages ligaments and bones to knit together firmly. A comfrey compress applied immediately to a sprained ankle can significantly reduce the severity of the injury. The combination of tannins, and mucilage helps to soothe bruises and scrapes. Skin problems - Comfrey oil or ointment is used to treat acne and boils and to relieve psoriasis. Comfrey is also valuable in the treatment of scars. Other medical uses - Hantavirus, Housemaid's knee.
NOTE. HOW MUCH TO TAKE
The leaf may be made as a tincture, and used under the direction of a herbal or medical practitioner for the purpose of healing stomach ulcers and other disorders, and in the respiratory system for conditions such as bronchitis. The leaf may also be made as a poultice or compress, and applied to sprains or bruised areas. It is also possible to make an infused oil from the leaf, which may be applied to the skin over an area where fractures or a break in the bone has occurred, and to scar tissue. Comfrey infused oil can be used as a massage oil to relieve stiff and aching joints in arthritic conditions. Comfrey ointment may be used instead of the oil in all cases mentioned.
How to make organic Comfrey fertilizer.
Comfrey is a very valuable plant to have in an organic garden, because it grows very vigorously and can be used to feed other plants. Comfrey has very deep roots that bring up nutrients from the subsoil, which are then stored in the leaves. Comfrey leaves can be used as a nutritious mulch or compost activator, but they can also be turned into a free fertilizer for your tomatoes and other fruiting plants.
Harvest your comfrey. Comfrey is a very vigorous plant. Once it has established in your garden, you will be able to harvest the leaves several times throughout the growing season. Simply cut the leaves right back and gather them up.
Put the comfrey in a bucket. To make liquid feed from your comfrey, you will need a bucket with a lid. If it has a tap as well, that makes life easier later on. Stuff your comfrey leaves into the bucket -- cram in as many as you can.
Weigh the leaves down. Put a brick or stone on top of the leaves to weigh them down.
Don't add water. Many recipes for making comfrey liquid feeds advise adding water, but when comfrey leaves rot down in water, they make a horrible smell. If you don't add water, the leaves will still rot down -- but they won't make a big stink about it!
Put the lid on.Put the lid on the bin to keep the rain and bugs out.
Wait 6 weeks.Comfrey leaves will take a few weeks to rot down -- you can keep checking on the progress, but expect it to
Drain off the liquid.Drain off the liquid feed -- it will look a little like a dark brown syrup and have very little odor.
Put the comfrey leaves in the compost.The remains of the rotted comfrey leaves can be added to the compost.
Start again!If your comfrey plant has grown a new crop of leaves, then you can start the process over.
Use your feed.Your comfrey liquid needs to be watered down 15:1 before use. It is high in potassium, and makes an excellent feed for flowers, tomatoes and peppers
Don't worry if your comfrey plant flowers before you cut it -- the flowers will attract bees to your garden and you can still use the leaves.