John&Jacq~s Garden

Marrubium vulgare is an exotic and bitter herb symbolic of good health

Marrubium vulgare (White Horehound, Common Horehound)

White Horehound or Common Horehound is an exotic plant and is a bitter herb symbolic of good health and has always been used to combat illness.

It is regarded as an invasive weed in many parts of Australia, namely in Victoria, south Australia and Tasmania because it takes over whole fields where there has been over-grazing and herd animals will not eat it.

Plant Profile, Culture and Propagation :

• Botanical Name: Marrubium vulgare (syn.: Marrubium album, Marrubium apulum, Ballota vulgare).
• Common Names: White Horehound, Common Horehound.
• Family Name: Lamiaceae.
• Etymology:The genus name, Marrubium is derived from the Latin word Marrubii meaning horehound.
• Origin:Native to Europe, northern Africa and southwestern and central Asia.
  It widely cultivated elsewhere around the world.
• Plant type: An ornamental, herbaceous and perennial flowering plant.
• Features: Marrubium vulgare is from the genus Marrubium that consists of 49 accepted species of plants.
  It is an upright or spreading and much-branched perennial herb that grows between 25-45 cm in height with stems branched or unbranched.
  Its stems are square in cross-section and have a greenish-white colour.
  Grey green leaves are ovate to circular, 1-70 mm long and 8-45 mm wide with a densely crinkled surface and are covered in woolly hairs.
  They have bluntly toothed margins an a rounded tip. The oppositely-arranged leaves are held on petioles.
  The lower leaves have longer petioles than the upper ones, up to 10-25 mm long.
  Its tiny flowers, measuring 6-12 mm long are white, tubular and borne in  dense clusters in the axils of the upper leaves. The flowers are two-lipped, the upper lip being divided into two lobes and the lower into three lobes.
  The flowers are surrounded by a persistent green calyx tube of fused sepals with ten narrow teeth.
  Flowers are hermaphrodite and are pollinated by bees.
  Eventually, the flowers will be followed by fruits.
  The fruit contains four seeds or nutlets enclosed in the old flower calyx, which has ten backward-curved teeth or spines.
  The seeds are 1-2.5 mm long, egg- or pear-shaped and with a slightly rough surface texture.

• Culture (Care): Marrubium vulgare or White Horehound can be easily grown with least maintenance.
  Light: Full sun or semi-shade.
  Moisture: Low to medium water requirements. It is drought resistant.
  Soil: Sandy, loamy, clay, moist and well-drained soils. It thrives best on poor soil.
  Others: Though very hardy, its needs weeding once established.
  Generally free from serious garden pests and diseases.
  Nonetheless, watch out for the orange and black stinkbug, Horehound bug which sucks the sap from new shoots and cause them to wilt and the larvae of Horehound plume moth that eat it while growing.
  For subtropical and temperate regions: Hardiness: USDA Zone 4a-9b.
  Marrubium vulgare or White Horehound is both drought and frost resistant and will grow in very poor soil. This beauty prefers warm average temperatures above 10°C and cold average temperatures above 0°C with dry summers. Horehound seeds can be started indoors or directly outdoors. If started indoors, sow in peat pots at a depth of 0.16 cm under topsoil. Do not bury the seeds past the recommended sowing depth as they will require direct light to germinate properly. Transplant or direct sow outdoors when all danger of frost has passed and the weather is warm. Horehound will thrive in an area of full sunlight and prefer temperatures that are over 23.89°C. Plants flower prolifically over most of the summer months and the whole plant has an interesting aroma often described as musky.

• Propagation: Easily propagated from seeds that will germinate in about 2-3 weeks.

• Usage: The essential oil of Marrubium vulgare or White Horehound contains potent antimicrobial and anticancer properties. The plant is used in certain candies for coughs and sore throat, as an expectorant, diaphoretic and as a laxative when taken in large doses. It is the source of an essential oil used in liqueurs. It is important for honey bees who are its primary pollinators. Besides, it’s used as a natural grasshopper repellent in agriculture. Ideal for low water gardens, butterflies and bees love the flowers.

External links:

• Wikipedia
• Dave’s Garden
• Flora of China
• Floral Encounters

Tags: butterfly plants, flowering plants, green, herbaceous, medicinal, ornamental, outdoor plants, perennials, white