Comfrey flowers are small and subtle yet still manage to make an attractive display against the handsome dark green leaves.
Comfrey is an Old World, old style medicinal herb once believed to cure almost anything, including, especially, broken bones. In fact, an older common name is "knitbone", and the genus name means "grow together" in Greek. Comfrey has been used as a healing herb since at least 400 B.C. The plant itself is a rampant, clump forming perennial with coarse, hairy leaves and clusters of pink or violet flowers on stems that start out upright, then invariably fall over. Stems and petioles are winged. Leaves are ovate, to 10 in (25 cm) long. The plant forms a clump up to 5 ft (1.5 m) tall and just as wide. Comfrey has a large tap root and seeds itself freely, to the point of being invasive. However, sterile, non-invasive cultivars are available.
Russian comfrey (Symphytum X uplandicum; a.k.a. S. peregrinum) is a cross between common comfrey and a species from western Russia, S. asperum.
Location Symphytum officinale occurs naturally throughout Europe, where it grows in moist meadows, along streams and ponds and along roadsides. S. asperum is native to the Caucasus Mountains of western Russia. Common comfrey has escaped from cultivation and become naturalized virtually everywhere it will grow.
Culture Light: Grow comfrey in full sun, or partial shade in hot climates. Moisture: Comfrey likes a rich, moist soil. It is not tolerant of prolonged drought. Hardiness: USDA Zones 3-9. Comfrey is a herbaceous perennial that dies to the ground in winter and comes back when warm weather returns. Propagation: Sow seed in spring. Comfrey is easily propagated by root cuttings and division, and sterile clones that do not produce seeds must be so propagated.
Jack's friend has a large comfrey plant growing in an urn that she keeps on the patio where she can easily pick leaves to put in the bath for a soothing soak.
Apparently comfrey really does have beneficial medicinal effects. Extracts from comfrey root and leaves contain a compound (allantoin) that, when used topically, seems to speed up the healing of wounds and burns by increasing the rate of cell regeneration. Comfrey also seems to have antibiotic properties. Comfrey extracts are used in ointments and creams marketed to help healing of varicose veins, bruises, burns and rheumatism. Commercial soaps, shampoos, and skin creams with comfrey are available. Comfrey extracts are used in homeopathic medicine for muscle and joint ailments.
Comfrey is used as a cover crop and a fertilizer. The long fleshy tap roots take up nutrients and minerals from the soil better than most plants, and these are made available in the leaves which can be composted, made into a fertilizer tea, or merely used as a mulch around other crops. Used as a fertilizer, comfrey is apparently an excellent source of organic potassium.
In the garden, comfrey thrives in a semi shady, moist environment and makes a good ground cover for a semiwild or woodland setting. Note, however, that the plant can become invasive. Every little broken off piece of root can start a new plant.
You can make your own comfrey extract. Mash up some fresh leaves in a blender and apply directly to burns, wounds, or even healthy skin to promote the growth of new cells and tissue. Dried leaves and roots can be ground up and steeped in hot water to make an ointment. (Don't boil, however, as that will destroy the active ingredient, allantoin.) Add ground comfrey roots or leaves to the bath water for a soothing, beautifying soak.
Various parts of the comfrey plant have been shown to induce cancer in laboratory rats. Taken internally, comfrey and its extracts can cause severe gastric distress, and may also cause liver damage in humans. Contact with the fresh leaves can irritate the skin for some people.