Horehound. The name likely calls to mind a big glass jar of vaguely molasses-flavored penny candy at the general store, or perhaps a package of old-fashioned dark brown cough drops. It may not, however, summon up a picture of the source of these products, a rugged perennial herb native to Europe, North Africa, and Asia, naturalized in the bleakest spots in North America and at home in almost any herb garden from Zone 3 to Zone 10.
The name may suggest a breed of gray dog, but that’s misleading. “Hore-” does mean hoary (gray or white) in Old English, but “-hound” is not canine; it’s simply an old name for the herb. The generic name Marrubium is the name by which the Romans knew the herb, and vulgare means common. Other opinions are that Marrubium refers to “an ancient town of Italy” or to a Hebrew word for bitter. Some references list horehound among the bitter herbs Jews eat at Passover, but according to Jo Ann Gardner (“Bitter Herbs: A New Look at the Plants of the Bible”, April/May 1990), it is not among the original bitter herbs of the Bible.
Several other herbs of the mint family also are called horehound, resembling Marrubium in that their flowers are clustered in the leaf axils. Water horehounds belong to the genus Lycopus, and black (stinking) horehound and Greek horehound to the genus Ballota.
In the language of flowers, horehound offers wishes for good health, and medical practitioners of many cultures have proclaimed its efficacy in treating a wide variety of ailments, of plants as well as people. Herbalists of old prescribed it for fevers and malaria and as an antidote for bites of snakes or rabid dogs, ingested poison, even magic! It was recommended for killing flies and for treating cankerworm in trees. Horehound has traditionally been used to treat disorders of the stomach, gall bladder, and respiratory system as well as hepatitis. Teas and cough syrups were popular preparations, but the herb was also taken as snuff (to treat “yellownesse” of the eyes), and fresh leaves were poulticed with honey “to cleanse foule and filthy ulcers.” Marrubiin, a chemical compound extracted from horehound, is an expectorant. Large doses of horehound are purgative and may cause irregular heartbeat, and the juice may cause dermatitis.
In England, horehound was made into “an appetizing and healthful” ale, and beverage teas are palatable if heavily sweetened to disguise the bitterness. Horehound candy is easy to make.
Horehound has erect, woolly, square stalks 2 to 3 feet tall, and wrinkled, scalloped, gray-green opposite leaves that are smooth or downy above and fuzzier below. From June to September, rings of small white flowers crowd in the leaf axils in prickly white calyces, and the minutely hooked seeds are carried to new sites on the fur of passing animals. The fresh leaves smell musky (some say fruit- or thyme-scented), but the odor disappears on drying; they taste very bitter. Horehound is an important bee herb.
Common horehound looks rather plain; it’s neither tidy like hyssop nor airy like fennel. Henry Beston (Herbs and the Earth, 1935) notes that in olden times “that wan nettle-like presence with its pointed, hostile bracts” would be relegated, along with other weedy herbs, to a “patch” somewhere outside the herb garden proper. Some gardeners prefer to plant the whiter, woollier, more ornamental silver horehound (M. incanum) or Spanish horehound (M. supinum), which is more compact and has pinkish flowers, but both of these are hardy only to Zone 7.
Creative gardeners have found ways of showing off common horehound to best advantage, however, teaming it with herbs of contrasting foliage such as tarragon and oregano, rue, southernwood, and butterfly weed. It contrasts nicely with glossy peony leaves and colorful California poppies in flower beds, too. Horehound tolerates poor, dry soil and is thus a fine choice for a xeriscape, especially in difficult sites such as next to driveways and sidewalks.
Indoors, horehound (pruned to keep it in bounds) can join small-leaved scented geraniums and upright and creeping thymes in dish gardens. The tops dry well and are attractive in either dried or fresh arrangements with artemisias, sages, bronze fennel, lemon verbena, myrtle, yarrow leaves, and variegated ivy, to suggest just a few possibilities.
Buy a plant or start horehound from seed. Well-drained soil is the secret to growing this herb, as too much moisture in winter can kill it. Sow seeds outdoors in spring or fall, 1/2 inch deep. Stratification (sowing the seeds in moist potting medium and refrigerating for a month or two) improves germination of seeds sown indoors. Thin the young plants to 10–20 inches apart; mature plants measure up to 2 feet across. Gardeners disagree whether propagation from root divisions and cuttings is difficult; divisions are taken in spring and cuttings in late summer. Layering is another propagation option. However, there is little need for any of these strategies, as horehound self-sows in the garden with no special treatment, and you will soon have all the plants you can use.