Friday, April 8, 2011

Hypericum perforatum - St. John's Wort

Hypericum perforatum - St. John's Wort,  also known as Tipton's Weed, Chase-devil, or Klamath weed. There are 400 species of St. John's Wort found throughout the world, H. perforatum is sometimes called Common St John's Wort to differentiate it from other species. 

The common name comes from its traditional flowering and harvesting on St John's day, 24 June. The genus name Hypericum is derived from the Greek words hyper (above) and eikon (picture), in reference to the traditional use of the plant to ward off evil.

St John's Wort is a perennial plant with extensive, creeping rhizomes. Its stems are erect, branched in the upper section, and can grow to 3 feet high. It has opposing, stalkless, narrow, oblong leaves that are yellow-green in color, with transparent dots throughout the tissue and occasionally with a few black dots on the lower surface. Leaves exhibit obvious translucent dots when held up to the light, giving them a ‘perforated’ appearance, hence the plant's Latin name.

Its flowers have five petals, and are colored bright yellow with conspicuous black dots. The flowers appear from June to August, followed by numerous small round blackish seeds which have a resinous smell and are contained in a three-celled capsule. There are many stamens, which are united at the base into three bundles. 

Although Hypericum perforatum is grown commercially in some regions of south east Europe, it is listed as a noxious weed in more than twenty countries.  In pastures, St John’s wort acts as both a toxic and invasive weed.  Ingestion by livestock can cause photosensitization, central nervous system depression, spontaneous abortion, and can lead to death.

Hypericum was prescribed in ancient Greece and it has been used ever since. It is widely known as a herbal treatment for depression. In some countries, such as Germany, it is commonly prescribed for mild depression, especially in children and adolescents.  It is used as an aromatic, astringent, resolvent, expectorant and nervine.  The crushed blossoms of the plant, when steeped in olive oil, turn the oil blood red; the oil is then used to treat wounds.

St John's Wort is also used in all pulmonary complaints, bladder troubles, in suppression of urine, dysentery, worms, diarrhoea, hysteria and nervous depression, haemoptysis and other haemorrhages and jaundice. For children troubled with incontinence of urine at night an infusion or tea given before retiring will be found effectual; it is also useful in pulmonary consumption, chronic catarrh of the lungs, bowels or urinary passages.

St John's Wort is generally well tolerated, the most common adverse effects reported are gastrointestinal symptoms, dizziness, confusion, tiredness and sedation.  St John's wort has been shown to cause multiple drug interactions, a physician's advise should be sought before using.  It has also been used as an ingredient for distilling vodka, and as a source of red, yellow, purple and orange dyes.

There are many ancient superstitions regarding this herb. The sign of the plant’s special association with the saint is in the yellow flowers that bloom at the summer solstice. When crushed, the flower buds yield a watery, purplish-red liquid, associated with the blood of the beheaded Saint John the Baptist, whose birth was celebrated on June 24. 

Its name Hyperieum is derived from the Greek and means 'over an apparition,' a reference to the plant’s use against supernatural agents (Grieve, A Modern Herbal, 1931), while others derive it from the practice of placing a sprig of St. John’s wort above an icon in the house for protective purposes. In ancient times, St Johnswort was thought to have magical properties and was used as a charm against storms, thunder, evil spirits, and witches.  

Some people believed that if you slept with a sprig of St. John's Wort under your pillow on St. John's Eve (the night before St. John's Tide), the Saint would appear in a dream, give his blessing, and prevent one from dying during the following year.  It was claimed to bring good luck if sprigs of the plant were hung about the house or carried as a charm and, if you slept with them under the pillow, you would dream of a future lover.

St. John's Wort is easy to grow from seed or root division in spring or autumn in any well-drained but moisture retentive soil and can do well in dry soils. Plants grow well in sun or semi-shade but they flower better when in a sunny position. It is a useful plant for attracting insects. The whole plant, especially when in bloom, gives off an unpleasant smell when handled.  Sow seed indoors in the spring, planting them outside to permanent positions in the summer.

Sources include:

USDA Forest Service:
A Modern Herbal:
Alternative Nature Online Herbal:
The Cloisters, Metropolitan Museum of Art:

No comments: