Blessed thistle, Cnicus benedictus (also known as Carduus benedictus and Carbenia benedicta ), is a member of the Asteracea, or daisy, family. The bitter-tasting, prickly thistles are considered "noxious weeds" when they take root and grow abundantly in open fields and meadows. The presence of this beneficial Mediterranean native, however, indicates fertile ground. The ancient Romans ate the leaf fresh and boiled the root as a vegetable. Thistle was once used as a nutritious fodder for cattle in Scotland, and the leaf, folded between two slices of buttered bread, was eaten with the breakfast meal. In the Middle Ages, thistle was one of the most common European medicinal herbs. Shakespeare wrote about it in his play, Much Ado About Nothing, with the advice: "Get you some of this distilled Carduus Benedictus and lay it to your heart; it is the only thing for a qualm." The belief in thistle as a heart tonic persists. One English herbalist, writing in the mid-twentieth century, declared blessed thistle "Good for all organs of the body, especially the heart and brain." Like many native European herbs, blessed thistle is credited with magical powers. It is said to be effective in exorcism, hex-breaking, and in purification spells. Grown outside the home, this blessed herb is said to attract peace, love, and harmony.
Blessed thistle is also known as holy thistle, St. Benedict thistle, cardin, and spotted thistle. This herbaceous annual has been cultivated for centuries as a medicinal herb. It was a component of many herbal remedies used to combat the plague. The herb was cultivated in monastery gardens as a cure for smallpox. Its specific name is in honor of St. Benedict, the founder of a holy order of monks.
Other thistles, including Carduus marianus or Silybum marianum, also sometimes known as holy thistle, Our Lady's milk thistle , Marian thistle, and wild artichoke have similar medicinal applications, particularly as liver tonics.
Thistles are naturalized throughout North America, found growing wild in sunny locations and stony soils. Blessed thistle grows from a thick taproot first forming a rosette of narrow leaves at ground level. The stems arising from the root are erect and hairy. Dark green, narrow leaves clasp the stem. They are deeply lobed, wavy and toothed on the margins, and veined. Each toothed lobe bears a prickly spine. Even the pale yellow flower heads, blooming at the top of the stem, are covered with prickly spines. The stem is reddish brown and branched reaching to two feet in length. The hardy thistle will self sow and thrive in good soil. If left to grow wild and uncultivated, thistles may become intrusive.
The entire plant is edible, though the prickly spines can be troublesome. The herb contains B-complex vitamins, calcium, iron , and manganese . Blessed thistle is considered by many contemporary herbalists and in traditional folk use as a tonic, astringent, diaphoretic (increases perspiration), emetic (induces vomiting ), and stimulant. Both the blessed thistle and milk thistles are recommended as a liver tonic, particularly when the liver disease is brought on by alcoholism . It has been used in treatment of jaundice and hepatitis . A tea from the leaves, taken warm, will increase perspiration, reduce congestion, and help to bring down fever . A mild infusion is astringent and may relieve diarrhea , but a very strong infusion is emetic and may cause nausea and vomiting. Blessed thistle is considered to be one of the best herbs to stimulate the flow of milk in lactating women (lactating women should always consult their physicians before taking this herb), and its emmenagogue action (promotes menstrual discharge) helps to regulate female hormone balance and relieve menstrual pain . Blessed thistle has also been used to treat the vaginal discharge known as leucorrhea. The herb is used in the commercial manufacture of herbal bitters , and is considered a general tonic and digestive. Its bitter properties increase the flow of bile and other gastric secretions. The herb may stimulate appetite and relieve flatulence. Blessed thistle is said to relieve melancholy and lethargy, and was traditionally fed to mentally ill persons. It acts to increase blood circulation and aids memory. Applied externally in poultice form, blessed thistle is a good treatment for shingles, wounds , and ulcers. The plant has antimicrobial properties. The essential oil has been shown to have antibiotic action against infections , specifically Staphylococcus aureus and S. faecalis. Blessed thistle has a history in folk use for the treatment of heart ailments, cancers, and as a contraceptive, but these, and other traditional uses, have not been confirmed by research.
Collect thistle on a hot and dry mid-summer afternoon, just as the herb begins to bloom. Harvest from the wild in areas where herbicides are not used, or from a cultivated garden patch. The leaves and flowering stems may be hung to dry in a light, airy room away from direct sunlight. Cut the dried herb and store in a clearly-labeled, dark-glass container. Seeds may be gathered in the fall.
Tincture: Combine 4 oz of fresh, or half as much dried, thistle leaf with 1 pt of brandy, gin, or vodka in a glass container. The alcohol should be enough to cover the flowers. The ratio should be close to 50/50 alcohol to water . Stir and cover. Place the mixture in a dark cupboard for three to five weeks. Shake the mixture several times each day. Strain and store in a tightly-capped, clearly labeled, dark glass bottle. A standard dose is 1–2 ml of the tincture three times a day. Tinctures, properly prepared and stored, will retain medicinal potency for two years or more.
Infusion: Use twice as much fresh, chopped herb as dried herb. Steep 1–2 teaspoons of finely chopped fresh or dried thistle per cup of boiled, unchlorinated water for 10–15 minutes. Strain and cover. Drink warm, sweetened with honey if desired. A standard dose is three cups per day. Strong infusions of thistle may cause diarrhea. A prepared herbal infusion will keep for up to two days in the refrigerator and retain its healing qualities.
There are no reported incidents of thistle toxicity. However, as with most medicinal herbs, they should not be taken during pregnancy . Children under two years should not be given the herb. Lactating women should consult with a qualified herbalist before using the herb. Strong infusions of blessed thistle may cause nausea and vomiting.
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