Horehound (Marrubium vulgare) – Herb garden

Horehound (Marrubium vulgare) is an attractive, ornamental herbaceous perennial flowering plant in the mint family. It has 2–5 cm long, thick, deeply wrinkled grey-green leaves that are oval to heart-shaped, with scalloped edges covered with wooly white downy hairs. The entire plant has a brisk, medicinal scent, especially when rubbed. The flowers are white, borne in clusters on the upper part of the main stem in summer.

The fruit contains four seeds enclosed in the old flower calyx, which has ten backward-curved teeth or spines. These seeds are brown or black in color, ovoid-shaped or pear-shaped, and have a slightly rough surface texture.

Scientific classification

Family: Lamiaceae
Genus: Marrubium
Species: M. vulgare
Scientific Name: Marrubium vulgare
Common Name: Horehound, White horehound, common Horehound, Woolly Horehound, Houndsbane, Soldier’s Tea.

How to grow and care for Horehound (Marrubium vulgare)

Light

It thrives best in full sun to partial shade.

Soil

It grows in most soil types, especially poor, dry and neglected soils. Prefers soils that are slightly alkaline or neutral but will grow on slightly acid soils. If soil is too acid will need to modify with lime.

Water

It is very drought tolerant. Excessive watering or standing water will kill the plant, especially if planted in a soggy site during the winter. During the summer, water no more than one time per week allowing the soil to dry between watering.

Temperature

It prefers average room temperatures 65°F – 75°F / 18°C – 24°C.

Fertilizer

Apply any organic fertilizer early in the spring to encourage new growth and some additional nitrogen after harvest to encourage new leaf growth using an organic or all-purpose liquid nitrogen. Avoid late summer fertilizer applications so plants harden off before fall dormancy.

Propagation

It can be easily propagated from seeds or cuttings in the early spring. To start plants inside, stratify (cold, moist) seed for 6-8 weeks before planting and can also be sown outside in fall where it is to grow. Seeds are very slow to germinate. Once established, the horehound readily self-propagates if allowed to flower and set seed.

Pests and Diseases

Horehound is not susceptible to many diseases or insect problems.

Harvest

The leaves are harvested for medicinal uses. Leaves are best harvested just before the plant starts to flower. Marrubium vulgare generally does not produce flowers until the second year. Some leaves may be harvested the first year. Tie the harvested leaves together in a bundle and hang them indoors out of direct sunlight or in a shady place to dry. In subsequent years, flowers and leaves should be harvested at the peak of bloom. Once dry, chop the leaves and blooms and store them in an air-tight container or jar. Dried horehound has a shelf life of about 1 year.

Benefits of Horehound (Marrubium vulgare)

• White horehound is a popular herbal medicine that is often used as a domestic remedy for coughs, colds, wheeziness, etc.
• Marrubium vulgare is an immune booster and contains vitamins A, B, C, E, essential fatty acids, iron, and potassium. The leaves and flowers have a minty-menthol flavor and are used in teas, candies, and cough drops.
• The leaves are used as a seasoning. Bitter and pungent, they are sometimes used to flavor herb beer or liqueurs. A mild pleasantly flavored tea is made from fresh or dried leaves, it is a favorite cough remedy.
• The leaves and young flowering stems are antiseptic, antispasmodic, diaphoretic, digestive, diuretic, emmenagogue, strongly expectorant, hepatic, stimulant, and tonic.
• The root is a remedy for the bite of rattlesnakes, it is used in equal portions with Plantago lanceolata or P. major.
• Marrubium vulgare is also used as a natural grasshopper repellent in agriculture.

Note:

• Horehound (Marrubium vulgare) is likely safe for most people when taken in food amounts or as a medicine. However, taking white horehound in very large amounts is possibly unsafe.
• Marrubium vulgare might lower blood sugar. Taking white horehound along with diabetes medications might cause your blood sugar to go too low. Monitor your blood sugar closely.
• Marrubium vulgare might lower blood pressure. This could cause blood pressure to go too low. White horehound should be used cautiously in people with low blood pressure or those taking medications that lower blood pressure.
• Pregnancy and breast-feeding: It is likely unsafe to take white horehound by mouth during pregnancy. It might start menstruation and could cause a miscarriage. If you are breast-feeding stick to food amounts of white horehound. There isn’t enough information about the safety of medicinal amounts. Don’t use white horehound on the skin if you are pregnant or breast-feeding. Not enough is known about the safety of topical use.
• might cause irregular heartbeat in people with heart problems. It’s best not to use it.