Growing and Saving the Seed Of Horehound

Latin name Marrubium vulgare is a cold-hardy perennial member of the mint family. This short, fuzzy-leaved shrub makes old-fashioned flavored cough drops and has a host of medicinal properties. Hardy from USDA zones 3-10.



Native to temperate regions of Eurasia. Historic uses range from treating stomach and gallbladder issues to treating snake bites! Today, horehound is still used as an expectorant, a common component of cough drops.


  • Ornamental
  • Traditional medicinal uses; still used as an expectorant in cough drops




  • Seeds germinate in 14-21 days (and sometimes more, as it is quite slow to germinate).
  • Start indoors 4-6 weeks before last frost.
  • Surface sow seeds and very lightly cover with a thin layer of soil.
  • Keep moist until germinated.
  • Ideal germination temperature is 68-75 F.


  • Prefers full sun and rich, well-drained soil.
  • Space plants 10 inches apart.
  • Harvest the leaves just after the plant begins to flower.
  • Keep flowers clipped if you want to prevent reseeding and spreading, otherwise plants will readily reseed and grow aggressively, like other mints.
  • Plants reach 18 inches tall.
  • Do not harvest more than 1/3 of the foliage in the first year.
  • In the second year and thereafter the plants will flower and leaves can be harvested freely.


  • A fairly pest- and disease-free plant, horehound's weedy behavior is its biggest issue. Clip flowers to keep plants from reseeding or grow in pots.


  • A very hardy perennial, horehound will flower in the second year.
  • Let flowers mature, turn brown, and dry.
  • Cut the stalks before the head shatters and shake seeds into a bag.