Boraginaceae: rhizomatous herbaceous perennial to 1.2 m (4ft) by 0.6 m (2ft in). Forming a clumps of erect stems bearing elliptic leaves to 25cm in length, and terminal clusters of nodding, tubular bell-shaped, cream or purple flowers 2cm in length in late spring and summer. Found growing in damp, often shady localities, in meadows, woods, especially near streams and rivers. Native to Europe, including Britain, south and east from Scandinavia to Spain, Siberia and Turkey.
The young leaves can be cooked or raw. The leaf is hairy and the texture is mucilaginous. It may be full of minerals but it is not pleasant eating for most tastes. It can be chopped up finely and added to salads, in this way the hairiness is not so obvious. Young shoots can be used as an asparagus substitute. The blanched stalks are used. Older leaves can be dried and used as a tea. The peeled roots are cut up and added to soups. A tea is made from the dried leaves and roots. The roasted roots are used with dandelion and chicory roots for making coffee.
Comfrey is a commonly used herbal medicine with a long and proven history in the treatment of various complaints. The root and the leaves are used, the root being more active, and they can be taken internally or used externally as a poultice. Comfrey is especially useful in the external treatment of cuts, bruises, sprains, sores, eczema, varicose veins, broken bones, internally it is used in the treatment of a wide range of pulmonary complaints, internal bleeding. The plant contains a substance called 'allantoin', a cell proliferant that speeds up the healing process. This substance is now synthesized in the pharmaceutical industry and used in healing creams. The root and leaves are anodyne, astringent (mild), demulcent, emollient, expectorant, haemostatic, and refrigerant, vulnerary. Some caution is advised, however, especially in the internal use of the herb. External applications and internally taken teas or tinctures of the leaves are considered to be completely safe, but internal applications of tablets or capsules are felt to have too many drawbacks for safe usage. The leaves are harvested in early summer before the plant flowers, the roots are harvested in the autumn. Both are dried for later use. A homeopathic remedy is made from the fresh root, harvested before the plant flowers. This has a very limited range of application, but is of great benefit in the treatment of broken bones and eye injuries.
The plant grows very quickly, producing a lot of bulk. It is tolerant of being cut several times a year and can be used to provide 'instant compost' for crops such as potatoes.
Sow seeds in spring, these seeds germinate rapidly depending on species and origin. If germination does not occur after 3–4 weeks a cooling period of 2–4 weeks is recommended. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Best grown in an open sunny site in a deep rich soil, but will handle some shade.