Comfrey (Symphytum officinale) is a perennial herb that is in the borage family. It is native to Europe and is commonly found in Britain and Ireland, growing in damp grasslands. There is also a Russian variety that is popular and grown widely. Its leaves are 12 to 18 inches long and somewhat hairy. Comfrey’s flowers can be blue, violet, cream, or pink, depending on the variety. Comfrey has a tremendous tap root that digs 8ft deep into the subsoil. It is a prolific grower, which enjoys plenty of nitrogen, but will grow under practically any condition. Comfrey can be propagated by both seed and root cuttings. Mature plants can be divided by splitting through the crown with a spade. This plant has many uses on the homestead, which we will now investigate…
Dynamic accumulators are very important in the designing of permaculture plant guilds. These plants have extremely deep tap roots which mine nutrients from the different layers of the soil profile. These nutrients are then brought to the surface to be used by surrounding plants. The authors of the book Integrated Forest Gardening call comfrey the “dynamic accumulator par excellence”. It is especially good at drawing potassium and calcium from the subsoil. Using the “chop and drop” technique, simply cutting leaves and letting them fall, comfrey can be used as a potassium rich fertilizer.
Comfrey leaves can be added to compost as a nitrogen source.
“Comfrey tea” can be made by soaking leaves in rain water for about 5 weeks. This tea is a nutrient rich fertilizer that can be used on garden crops, especially those that benefit from additional potassium.
Dried comfrey was traditionally used as a supplemental feed for farm animals. It tests about 26% protein, high in minerals, and is low in fiber. It was fed to many types of livestock but its primary uses were for chickens, hogs, and other non-ruminants. There is plenty of historical evidence that horses, goats, sheep, cattle, and other stock were also fed comfrey.
Traditionally, comfrey is known by the name “knitbone” or “boneset” and this was derived from the Latin name Symphytum that comes from the Greek symphis, which means “growing together of bones”, and phyton, “a plant”. This in itself speaks to the long tradition of using comfrey for broken bones! Other medicinal uses include bronchial problems, sprains, arthritis, gastric ulcers, burns, acne, and other skin conditions.
Mountain Rose Herbs lists the following as comfrey’s constituents “Tannin, rosmarinic acid, allantoin, steroidal saponins, mucilage, inulin, pyrrolizidine alkaloids, Gum, Carotene, Glycosides, Sugars, Beta-sitosterol, Triterpenoids, Vitamin B-12, Protein, Zinc. The main healing ingredient in comfrey leaf appears to be a substance called allantoin, which encourages the rapid growth of cells.”
While comfrey used topically is considered safe, recently there have been warnings against using it internally. The warnings come from studies that show pyrrolizidine alkaloids can cause liver damage and possibly cancer. It should be noted that the studies done singled out pyrrolizidine alkaloids and did not include the other compounds found in comfrey. The studies also used huge amounts of pyrrolizidine alkaloids, much more than is found in the plant. Historical evidence of people ingesting comfrey for 1000’s of years (without ill effect) should be taken into account when deciding whether or not one should use it that way.
See more North Country Farmer plant profiles here.