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St. John's Wort (Hypericum perforatum)

By Contributor ; Updated September 21, 2017

This tough little perennial shrub grows 12-36 inches tall and is covered with pretty, fragrant yellow flowers from mid to late summer. The flowers have 5 petals and clusters of feathery gold stamens. The dark green leaves have oil glands which look like tiny perforations on their undersides.


St. John's wort is usually propagated from runners in the autumn or by seed sown early in the spring. The plant does best when planted on an average soil and prefers dappled shade or full sun. the plants grow rapidly but are short lived, usually lasting only five or six years. Because of their dense, compact habit of growth they rarely need pruning, but if it is necessary to cut off deadwood, do so in early spring. New plants can be started from softwood cuttings of young growth in late spring or early summer.


Cut flowers when fully open and pick leaves as required. Always harvest before the heat of the day.

Medicinal Uses

Use caution as this plant can cause photosensitivity in some people.

For Depression
Many clinical trials show Saint-John's-wort to be useful in treating mild depressive states. Studies in 3,250 patients found improvement or total freedom from symptoms in about 80% of the cases treated, with only 15% not responding.

In Germany, the most popular prescription drug of any type, natural or synthetic, for the treatment of mild depression is a concentrated extract of the flowers and leaves of Saint-John's-wort, often simply called hypericum. There, just under 200,000 prescriptions per month are filled for a single brand (Jarsin), compared with about 30,000 per month for fluoxetine (Prozac). This figure does not include sales of other hypericum products, whether they are prescribed or self-selected. Approximately 80% of the sales are prescriptions, which allows their cost to be reimbursed by the German health-insurance system.

When preparing St. John's Wort grown in your garden, use two to four grams of dried herb daily. The herb can be prepared as a tea. Both leaves and flowers are used.

For Other Conditions
For medicinal use, prepare a tincture or infusion of the aerial parts.

  • It is useful as a wound healer, encouraging the formation of granulation tissue and promoting nerve repair.

  • Taken internally, the red oil from the plant helps to heal stomach ulcers.

  • Take an infusion or tincture internally for rheumatism, or massage the oil into the joint.

  • Treats nerve-related disorders such as neuralgia, sciatica and shingles.

  • Eases symptoms of menopause.

  • The oil is good to use topically for wounds, sunburn, burns, and post-operative scars.

  • In Germany it is traditionally used for colic, aches and pains, inflammation of the digestive tract and bed-wetting.


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