Official opinions vary on the medical efficacy of the common horehound plant (Marrubium vulgare), also known as white horehound. The German government approved horehound as an ingredient in heartburn and liver medications, and most European nations allow it as a primary cough drop ingredient. The U.S. Food and Drug Administration, on the other hand, forbids the use of horehound in cough drops. Yet at home or abroad, horehound still boasts fans who appreciate its pungent flavor and cough-soothing abilities, not to mention its handsome appearance in the herb or flower garden. Never ingest horehound in any form without consulting a medical professional first.
Physicians discovered horehound leaves’ beneficial properties several millennia ago. References to the herb appear in ancient Hebrew, Roman and Egyptian texts. Egyptian priests called the herb “Star of Horus” after the falcon-headed god worshipped in ancient Egypt. Medieval British herbalists John Gerard and Nicolas Culpepper both wrote of the herb’s respiratory benefits, particularly for illnesses featuring phlegm-heavy coughs and labored breathing.
A hardy perennial, the bushy, multi-branched horehound reaches about 18 inches in height. Its wrinkled leaves sport tiny hairs, giving them a velvety appearance. The flowers are tiny and white, and grow in clusters along square stems. Because tiny hairs encase the entire plant, this very down lends the plant a silvery, ethereal appearance in a cottage garden which its close cousin, the mint plant, lacks.
Horehound’s cold and cough-fighting chemical components include tannins, said to lower blood pressure; Vitamin C, a collagen-building anti-oxidant; and mucilage, which turns a stubborn cough into a mucus-producing one. Another key ingredient, marrubin, improves digestion and respiratory function, and may even possess cancer-fighting properties, according to a study at the University of California.
Sow horehound seeds after all danger of frost passes, or plant nursery seedlings in early summer. Other propagation methods include taking cuttings from the plant's stem in late summer, or dividing the plants in mid-spring. Thin or transplant horehound to about one foot apart. Horehound prefers soil on the dry, infertile and alkaline side. Add limestone or wood ashes to raise your future horehound patch's pH level if it is lower than 7.0. Give the plants a sunny spot, preferably with some wind protection. Prune these hardy perennials in the spring, before they flower. Divide the plants every few years. To harvest leaves and flowers, pick at any time during the growing season.
Horehound Candy Recipe
Herbalist Lesley Bremness provides the following recipe for home-made cough drops, which many people enjoy as a simple hard candy: Combine 4 ounces fresh horehound leaves, ½ teaspoon crushed aniseed, 3 crushed cardamom seeds and 2 ½ cups water. Simmer 20 minutes, strain and return to pan. Add 2 cups white sugar and 1 ½ cups brown sugar; boil on medium heat to the “hard crack” stage. Pour into oiled tray and score the pieces once the mixture has cooled slightly. Again, do not take items containing horehound without consulting your doctor first.
According to the online herbal encyclopedia “A Modern Herbal,” infusing horehound leaves in milk and setting it in a shallow dish will attract and drown flies. Steeping the leaves in boiling water, on the other hand, makes an effective tree spray to combat cankerworm. Plant horehound in your garden to increase pollination; the plant’s flowers attract bees.