hypericum St. John’s-Wort, Hypericum perforatum

Family: Hypericaceae, the St. John’s Wort Family

Description: Non-native perennial herb 0.3-1m tall. Flowers with 5 yellow petals and black dots along edges. Leaves with many translucent dots (looks perforated).

Abundance: Common

Habitat: Fields, roadsides, waste areas

Plant Parts Used: Flowers

Medicine: Nervine, antidepressant, uplifting, bruises, sore muscles, strains, menopause anxiety

hypericum (2)St. John’s-Wort has become quite popular sold in capsule form as an antidepressant in many natural food stores. St John’s Day is close to the summer solstice, the longest day of the year—St. John’s-Wort was so named because it was believed that the plant helped people take in extra sunlight, thereby helping treat depression. Ray says this plant is a good nervine, often used for mild depression especially for people who are in the dark a lot. However, taking too much can make people sensitive to the sun. Deb also described St. John’s-Wort’s use for treating mild to moderate depression due to lack of light, especially from September through March. She said this plant has an uplifting quality that moves us out of a dark state of mind. Sue said the flowers can be made into tea or tinctures for treating depression or seasonal affective disorder. Terry-Anya also described a similar effect—she called St. John’s-Wort a protective. She told me that this plant is especially helpful for people dealing with depressing life issues by helping people “not be ground down by” those problems. Deb said that St. John’s-Wort supports the nervous system, especially as a tea or tincture. This effect also helps relax the nervous system during menopause and decreases stress-related anxiety. However, St. John’s-Wort can interfere with other medicines, such as the birth control pill. The Cherokee used a decoction as an abortifacient and the Iroquois used the roots to prevent sterility.

Used externally, an oil made of the flowers can be rubbed on the skin to relieve sore muscles, bruises, and strains. Deb said this oil is especially good at relieving the inflammation and pain in fingers, toes, and in the tailbone. The oil can also be used during and after labor for healing tears, inflammation, and pain. Terry-Anya said it is especially healing following radiation treatments. This oil can be made by soaking the flowers in olive oil and leaving the closed jar in the sun for a couple weeks. This process makes a rich, red oil. Another way of identifying this plant is by crushing the petals between the fingers; this too will stain fingers a subtle red.

Caution: According to Turner and Von Aderkas, St. John’s-Wort’s photosensitizing properties can cause skin irritation when exposed to sunlight, though this effect has not been proven to be particularly harmful to humans. Turner and Von Aderkas say that the usual dosage given is typically not enough to cause problems. However, grazing animals that consume St. John’s-Wort may experience “swelling, blistering, and lesions on their unprotected skin.” People should avoid bright sunlight and UV-treatments when taking St. John’s-Wort.

St. John’s-Wort may also interfere with many prescription drugs. Turner and Von Aderkas list some examples of the prescription drugs that may interact with the use of St. John’s-Wort, including “immunosuppressants, cardiac glycosides, protease inhibitors, anticoagulants, sedatives, antidepressants, oral contraceptives, and some cancer drugs.” St. John’s-Wort should not be used during pregnancy.

Note: This post is part of my Plants and People series. See my Plants and People page for more information about the project and the people referenced in this post.


  • Chilton, Patti. Telephone interview. 31 Oct. 2010.
  • Hayes, Terry-Anya. Personal interview. 27 Oct. 2010.
  • Michener, Martin C. Botany Everywhere: Woods, Field, Home, and Garden Plants of NE USA, Third Edition. Hollis, NH: MIST Software Associates, Inc., 2009. PDF.
  • Mittelhauser, Glen H., Linda L. Gregory, Sally C. Rooney, and Jill E. Weber. The Plants of Acadia National Park. Orono, Me.: University of Maine, 2010. Print.
  • Moerman, Daniel E. Native American Medicinal Plants: an Ethnobotanical Dictionary. Portland, Or.: Timber, 2009. Print.
  • Reitze, Raymond and Nancy. Personal interview. 8, 15 Oct. 2010.
  • Soule, Deb. Personal interview. 4 Feb. 2011.
  • Szwed, Sue. Personal interview. 12 Nov. 2010.
  • Turner, Nancy J., and Patrick Von Aderkas. The North American Guide to Common Poisonous Plants and Mushrooms. Portland: Timber, 2009. Print.