Location of Comfrey

This section will address the botanical information about comfrey, where comfrey grows, and growing requirements.

Comfrey is a member of the order of plants called Boraginaceae, or the Borage Family. Common names for comfrey include knitbone, bruisewort, wound wort, gum plant, healing herb, slippery root, consound, blackwort, wallwort, black root, nipbone, knitback, yalluc (Saxon), Schwarzwurz (German), consuelda, and sinfito (Spanish.) “The name comfrey is a corruption of con firma, in allusion to the uniting of bones it was thought to effect, and the botanical name, Symphytum, is derived from the Greek symphyo (to unite.)”

Fortunately for the herbal enthusiast, comfrey is easy to grow. I have grown comfrey successfully all over the United States. My gardens in the Eastern states, the Midwest, the Rocky Mountain states, and on the West coast have all known this marvelous plant. Peterson’s Field Guide to Western Medicinal Plants and Herbs says that it is found “Escaped. Alien. Often cultivated; persistent.” I am familiar with its persistence, as it seems that the more it is cut, the more it grows, whether the cutting be taken from the leaf or the root. “As an ornamental plant, Comfrey is often introduced into gardens, from which it is very difficult to eradicate it when it has once established itself, a new plant arising from any severed portion of the root.” Comfrey rootstocks should be planted in the spring, and its leaves can be harvested from April to September. However, its roots contain the most allantoin, which is its primary medicinal agent, from January through March. Additionally, the leaves should be gathered between 5 and 6 in the evening when the healing properties are most concentrated.

The following two paragraphs describing comfrey’s appearance and growth characteristics are taken nearly verbatim from an agricultural extension service internet website.

“Comfrey is a herbaceous perennial plant with short, thick, tuberous roots, a deep and expansive root system. Comfrey begins growth in early-April and by early May compact clusters of young leaves are visible in the crown of the old plant. Within a few weeks, the leaf blades with long petioles have grown to over 12 in. high. Basal leaves are large, lance-shaped, stalked, and coarsely hairy. The stem elongates rapidly and reaches a height of over 3 feet. Upper leaves do not have long petioles and are attached closely to the stem.”

“Flowering starts in late May or early June and continues until fall. Leaves on flowering, erect stems are sessile or decurrent, and decrease in size up the stem. The bell-shaped flowers with pedicels are in terminal cymes or one-sided clusters. Flowers of common comfrey are usually creamy yellow but white, red, or purple types have been found in Europe. Prickly comfrey has pink and blue flowers while Quaker comfrey has blue, purple, or red-purple flowers. Seed production is rare, and crops are usually established from root cuttings and crown divisions. Vegetative growth does not cease with the start of flowering, and the plant will add new stems continuously during the growing season. The plant will grow rapidly after harvest and flower again.” Cutting back the flowers will cause the plant to bush out rather than grow up tall and spindly, thus producing a greater crop of leaves.

There are three plant species in the genus Symphytum known as comfrey. “1) Wild or common comfrey, Symphytum officinale L., is native to England and extends throughout most of Europe into Central Asia and Western Siberia. 2) Prickly or rough comfrey [S. asperum Lepechin (S. asperrimum Donn)], named for its bristly or hairy leaves, was brought to Britain from Russia about 1800. 3) Quaker, Russian, or blue comfrey [S. × uplandicum Nyman (S. peregrinum Lebed.)] originated as a natural hybrid of S. officinale L. and S. asperum Lepechin. This hybrid was called Russian or Caucasian comfrey in reference to its country of origin.” Quaker comfrey. (named after the religion of Henry Doubleday, the British researcher responsible for promoting comfrey as a food and forage), originated from cuttings of the Russian hybrid, which were shipped to Canada in 1954. The majority of comfrey grown in the United States can be traced to this origin.

In addressing the environmental requirements, Comfrey produces the highest yields in full sunlight and under cooler conditions although it can also successfully be grown in partial sun. Comfrey’s deep root system protects its leaves from wilting during extended periods of drought. Additionally, it is also very frost resistant.

Comfrey is adaptable to many soils, but prefers moist, fertile soils. Thin soils over rock will give a poor crop, but on light sands and loams, it will be productive if adequate nutrients are present. If proper weed control and soil fertility is maintained, comfrey plantings should last indefinitely (more than 20 years.)

Comfrey has usually been grown without herbicides, and diseases have not been a serious problem with comfrey in the United States. However, “comfrey rust fungus (Melampsorella symphyti) overwinters in roots and reduces yield of old plantings in Great Britain.” Comfrey plants grown in the United States do not suffer from this disease, however, due to plant quarantine regulations on imported roots or plants.