However, the unassuming nature of houseleeks (another of Sempervivum’s familiar names) belies their fascinating history and understates their medicinal value. In ancient times, houseleeks were credited with the power to ward off witches, and when planted upon a home’s roof they conferred prosperity and safety to those who dwelled within. The Roman emperor Charlemagne commanded his subjects to plant houseleeks on their roofs to prevent lightning strikes, a practice that probably stemmed from the ancients’ belief that houseleeks were earthly manifestations of Jupiter and Thor, the Roman and Norse gods of thunder. Indeed, regional labels for houseleeks still include Jupiter’s beard, Thor’s beard, and Donnersbart (thunderbeard). Even today, many roofs in Wales are adorned with houseleeks.
According to the Physicians Desk Reference for Herbal Medicines, Sempervivum’s fresh leaves and juice house a variety of pharmacologically active constituents, including tannins, mucilage, isoflavonoids, and various fruit acids (malic, isocitric, and succinic). Leaves should be collected prior to flowering, as once the distinctive, upright peduncle rises above a mother rosette its salutary properties diminish. This botanical feat is the “last hurrah” for a mature rosette; it dies shortly after dispersing its many-seeded, star-shaped fruit. Fortuitously, Sempervivum’s growth habit provides many “satellite” rosettes that eventually fill the void left by the departed parent. Herbalists who wish to propagate Sempervivum crush the fruit, separate the seeds, and stratify them before growing them out on a coarse cactus mix. (Keep in mind that Sempervivum doesn’t breed true, so you may get some odd-looking progeny if you have more than one variety growing in your neighborhood.)
Sempervivum’s leaves can be macerated or bruised and applied as a poultice, and individual leaves make handy little “spot” bandages. Entire plants can be crushed, pounded or pressed to collect the juice – a labor-intensive process – or you can steep 15-20 grams of fresh leaves in a quart of boiling water for 10 minutes to prepare an infusion. Infusions and decoctions are generally used internally, while the juice – either full-strength or diluted – is used externally.
Sempervivum’s anti-inflammatory, cooling, and astringent properties have been exploited by humankind for centuries. A plucked leaf’s chewed or crushed edge will bring immediate relief to insect bites and stings. A bruised leaf secured to a toe or finger with a Band-Aid or strip of tape is reputed to be a good remedy for corns and warts, and soaking your feet in dilute juice is a wonderful way to end a harrying day. Gargles and mouthwashes, prepared from equal parts of water and juice and sweetened with a drop or two of honey, assuage sore throats and mouth ulcers. Undiluted Sempervivum juice makes an excellent drop for a hot toddler’s ear. Poultices and compresses prepared from crushed leaves or a cloth soaked in dilute juice have been used to treat burns, skin ulcers, abrasions, rashes, ringworm, impetigo and superficial bruises.
Traditionally, Sempervivum has been taken internally for a multitude of ailments, including diarrhea, dysentery, menstrual cramps, fever, amenorrhea, tonsillitis, headache, worm infestation, and poor hearing. Dioscorides claimed Sempervivum improved poor eyesight, Pliny believed it cured insomnia, and Culpeper recommended it for gout. Modern research suggests Sempervivum exerts liver-protective and antioxidant effects.
The most convenient way to take Sempervivum is as an infusion: drink one cup every three hours as needed. (When taken internally, undiluted juice in large doses acts as a purgative.) Keep unused infusions, decoctions and juice refrigerated; it isn’t clear how long these preparations remain viable, so it’s best to discard them after one week.
Physicians’ Desk Reference for Herbal Medicines, Second Edition: Houseleek. Thomas Fleming, PharmD, Chief Editor. 2000