Comfrey is a stout, vigorous perennial plant that bears large, tapered, prickly leaves and purple, pink, blue, or white bell-shaped flowers. It has been used as a medicinal plant since ancient times, and its botanical name refers to the plant’s traditional use to repair broken bones: Symphytum is from the Greek symphytos, which means “to unite.”
“Comfrey” comes from the Latin con firma, meaning “with strength.” Women whose virginity was in doubt were once encouraged to bathe before marriage in water infused with comfrey. The herb was believed to repair a woman’s hymen, and in some places it is still used for this purpose, considered to be able to repair tears in the vagina. Although the leaves were at one time added to soups, stews, and salads, this use is no longer recommended due to the plant’s toxicity.
Common Names: Comfrey, Healing-Herb, Knitbone
Description: Upright perennial, up to 3 feet tall; purple, pink, blue, or white tubular flowers on short, curved racemes; deep green, hairy leaves up to 10 inches long; black rhizomes are white inside
Hardiness: To Zone 3
Flowering: May through frost
Parts Used: Leaves and rhizomes
Range/Habitat: Native to Europe and Asia, naturalized throughout North America; found along stream banks and in moist meadows
Comfrey root and leaves contain allantoin, a chemical that promotes cell proliferation and may contribute to the healing properties of the plant. The herb has been used to heal burns and insect stings, as well as broken bones, strains, and sprains. A paste of the root, spread on cloth, will stiffen into a cast. A compress of comfrey tea, applied immediately after a sprain, may help reduce the sprain’s severity. Comfrey is a common ingredient in herbal ointments and salves. A synthesized form of comfrey is used in pharmaceutical hemorrhoid preparations.
Caution: Comfrey contains pyrrolizidine alkaloids, which may cause liver damage and are considered toxic. Comfrey leaves should not be used internally, except under the advice of a qualified medical professional. Comfrey root preparations should not be used internally under any circumstances, nor should they be applied to broken skin. The herb should not be used in any form by pregnant or nursing women. Poisonings have occurred when people have collected the highly toxic foxglove (Digitalis purpurea), mistaking it for comfrey.
How to grow it
Comfrey grows wild in marshy areas, meadows, and ditches, but it will thrive in any good garden soil in sun or partial shade. The plant can be invasive. To keep it contained, many gardeners plant it in a submerged pot with drainage holes. Plant seeds or root divisions in spring or fall. Harvest leaves in summer; lift the roots in fall.