Hero

My Garden

Marrubium vulgare
White Horehound
Marrubium vulgare
Marrubium vulgare, commonly known as White Horehound, is a perennial herbaceous plant belonging to the mint family (Lamiaceae). It is characterized by its square, woolly stems and crinkled, soft, grey-green leaves covered in fine hairs, giving it a somewhat frosted appearance. The plant produces small, densely clustered white flowers in whorls around the stem nodes, typically blooming from late spring to autumn. Native to Europe, North Africa, and Asia, White Horehound is well-adapted to dry, disturbed soils and full sun. It has a distinctive bitter taste and aromatic scent, which historically has made it a popular herb for various medicinal purposes, particularly for coughs and colds, and also for flavoring candies and beverages.
CategoryDetails
Invasive StatusInvasive Status
Plant TypePerennial plant
Culinary UsageEdible plant
Medicinal UsageMedicinal Usage
Duration to maturity4 months to harvest
Estimated Plant Lifespan3 years lifespan
Sun Requirements6+ hours direct sunlight (Full Sun)
Pollination

Method: animal

Notes: White Horehound is primarily pollinated by insects, especially bees (Apis mellifera, Bombus spp.). Its small white flowers are attractive to a variety of pollinators. While it can self-pollinate to some extent, cross-pollination by insects is common and promotes seed set.

Watering Requirements

Method: top water

Frequency: when soil is dry

Notes: White Horehound is highly drought-tolerant once established. It prefers dry conditions and well-drained soil. Water deeply but infrequently, allowing the soil to dry out completely between waterings. Avoid overwatering, as this can lead to root rot, especially in heavy soils.

Humidity Requirements

Level: low

Care InstructionsWhite Horehound is a low-maintenance plant. To prevent excessive self-seeding and encourage bushier growth, deadhead spent flowers regularly. In late winter or early spring, prune back the plant by about one-third to encourage new, vigorous growth and maintain its shape. It generally does not require fertilization, especially in poor soils where it thrives, but a light application of compost can be beneficial.
Alternative NamesHorehound, Common Horehound, Common Hoarhound, Hoarhound, Marvel, Whitehoarhound, Prasium marrubium
Salvia rosmarinus
Rosemary
Salvia rosmarinus
Both White Horehound and Rosemary thrive in similar conditions: full sun, well-drained to dry soil, and tolerate poor fertility. Their shared preference for arid environments makes them good companions, and Horehound's aromatic properties may deter some common garden pests, indirectly benefiting rosemary.
Lavandula angustifolia
Common Lavender
Lavandula angustifolia
English Lavender shares White Horehound's love for full sun, low water, and well-drained soil. Both plants are highly aromatic and attract beneficial pollinators like bees, enhancing biodiversity in the garden while requiring similar low-maintenance care.
Thymus vulgaris
common thyme
Thymus vulgaris
Thyme and White Horehound are well-suited due to their identical needs for full sun, poor to moderately fertile soil, and excellent drainage. Planting them together creates a harmonious, drought-tolerant, and low-maintenance herb patch.
Urtica dioica
great stinging nettle
Urtica dioica

While not invasive, Stinging Nettle can be quite vigorous and establish dense patches, outcompeting Marrubium vulgare for light, water, and nutrients, especially in richer soils where horehound might struggle.

Plantago major
greater plantain
Plantago major

Broadleaf Plantain is a robust weed that can rapidly colonize disturbed or compacted soils. Its broad leaves can shade out smaller plants like Marrubium vulgare, and its fibrous root system competes effectively for water and nutrients.

Aphids

Aphids are small, soft-bodied insects that cluster on new growth and the undersides of leaves. They suck plant sap, leading to distorted, curled, or yellowed leaves, and can excrete a sticky substance called honeydew, which may encourage sooty mold.

Slugs and Snails

These gastropods can chew irregular holes in leaves, especially on young plants or tender new growth. Damage is often more prevalent in damp conditions, and silvery slime trails are usually visible near affected plants.

Steps:

    • Sow seeds directly outdoors in early spring or autumn, or indoors 6-8 weeks before the last frost.
    • Light is required for germination, so press seeds lightly onto the soil surface without covering them deeply.
    • Maintain consistent moisture until germination occurs, which can take 10-20 days.
    • Thin seedlings to 12-18 inches apart once they are large enough to handle.
    • In spring or autumn, carefully dig up a mature horehound plant.
    • Gently divide the root ball into smaller sections, ensuring each section has roots and some foliage.
    • Replant the divisions immediately at the same depth as the original plant.
    • Water thoroughly after replanting.
    • Take 4-6 inch softwood cuttings from new growth in spring or early summer.
    • Remove leaves from the bottom half of the cutting.
    • Dip the cut end in rooting hormone (optional).
    • Insert cuttings into a well-draining potting mix.
    • Keep the medium moist and provide warmth and indirect light until roots develop.

Bone Meal

Provides phosphorus for strong root development and overall plant vigor, beneficial especially for establishing new plants.

Compost

Improves soil structure, drainage, and provides a slow release of nutrients, which is beneficial for White Horehound though it tolerates poor soils.

Neem Oil Spray

A natural insecticide and fungicide that can be used to control aphids and other soft-bodied pests by disrupting their feeding and reproduction.

Diatomaceous Earth (Food Grade)

A natural, non-toxic powder that creates a physical barrier and dehydrates slugs and snails, effectively deterring them from plants.