St John’s Wort, also known as Tipton’s Weed or Klamath Weed is a perennial herb indigenous to Europe which has been introduced to many temperate areas of the world and grows wild in many meadows.

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, by hanging plants over a religious icon in the house during St John’s day. The species name perforatum refers to the presence of small oil glands in the leaves that look like windows, which can be seen when they are held against the light.

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 and has introduced populations in South and North America, India, New Zealand, Australia, and South Africa. In pastures, St John’s wort acts as both a toxic and invasive weed. It replaces useful vegetation to the extent of making productive land unviable or acts as an alien species in natural ecosystems. Ingestion by livestock can cause photosensitization, central nervous system depression, spontaneous abortion, and can lead to death.

St John’s wort 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, adolescents, and where cost is a concern. Standardized extracts are generally available over the counter, though in some countries a prescription is required. Extracts are usually in tablet or capsule form, and also in teabags and tinctures. Herbalists are more likely to use a fluid extract than a tincture.

Planted in Nassau County Extension Demonstration Garden