Heal all, a low-growing mint relative, is native to Eurasia and can be found in temperate regions worldwide. Naturalized throughout North America, the plant spreads so readily that it’s often considered an invasive weed. Its scientific name can be traced to a fever known as “the browns” (for the brown-colored tongue coating of infected patients), which spread through German armies during the 16th century. Because heal all was a common treatment for the browns, the herb became known as Brunella, and later Prunella.
Common Names: Heal All, Self-Heal
Description: Low-growing perennial with creeping rhizomes; reddish stems bear small, oval leaves and spikes of violet-blue blooms
Hardiness: Hardy throughout most of North America
Flowering: Midsummer to autumn
Parts Used: Flowers, leaves, and stems
Range/Habitat: Native to Eurasia, naturalized throughout temperate regions
The minty flavored leaves, stems, and flowers of heal all can be used in salads, soups, or stews or boiled as a potherb. To make a tasty, healthful tea, bring 2 cups of water to a boil, then pour the water over 1 ounce of fresh leaves or flowers. Steep for 5 minutes, then strain.
As its name suggests, heal all has been used to alleviate a wide range of conditions. It can be taken as a tea, tincture, mouthwash, poultice, or salve. The plant is rich in rosmarinic acid, which regulates the production of thyroid hormone, making it useful in the treatment of overactive or underactive thyroid.
As an immune-system stimulant with antiviral properties, it may be beneficial in the treatment of the herpes simplex virus. The herb also soothes inflamed mucous membranes and has been taken traditionally to relieve gingivitis, sore throat, and diarrhea. In lab studies, it has been found to lower LDL (“bad”) cholesterol.
Practitioners of traditional Chinese medicine use an extract of the herb to treat hypertension. The great 17th-century English herbalist Nicholas Culpeper (1616–1654) recommended applying heal all externally as a plaster or unguent to treat skin wounds and other sores. Heal all is a key ingredient in many natural skin-care products.
How to grow it
Heal all commonly grows on sunny banks, in grassy areas, and in open woodlands. It can be propagated by seed or by division of the creeping rhizomes, although the plant spreads quickly and is considered weedy. For best germination, chill seeds for about 1 month before sowing them indoors in flats. Transplant 8-week-old seedlings outdoors in early spring, spacing plants about 1 foot apart in either full sun or partial shade. Keep the soil evenly moist for the first year. Harvest the flowering stems just before the blooms open.