Hypericum is a genus of flowering plants in the family Hypericaceae. The genus has a nearly worldwide distribution, missing only from tropical lowlands, deserts and polar regions. Many Hypericum species are regarded as invasive species and noxious weeds. All members of the genus may be referred to as St. John's wort, and some are known as goatweed. The white or pink flowered marsh St. John's worts of North America and eastern Asia are generally accepted as belonging to the separate genus TriadenumRaf.
Hypericum maculatum, commonly known as imperforate St John's-wort, or spotted St. Johnswort, is a species of perennial herbaceous flowering plant in the family Hypericaceae. It is native to Europe and Western Asia where it grows in moist meadows.
Hypericum mutilum is a species of St. John's wort known by the common name dwarf St. John's wort. It is native to parts of North America and is present in other parts as an introduced species. It is an annual or perennial herb taking a multibranched erect form up to about 60 centimeters tall. The oval green leaves are one or two centimeters long and are covered in tiny glands. The inflorescence is a compound cyme of tiny flowers. H. mutilum subsp. mutilum and subsp. boreale have a diploid number of 16, and H. mutilum subsp. boreale can have a diploid number of 18.
Hypericum olympicum, commonly known as the Mount Olympus St. John's wort, is a species of flowering plant in the family Hypericaceae found in the Balkans and Turkey and introduced to western Europe. It has been widely cultivated for centuries because of its large, showy flowers, which are far larger than those of most other species in Hypericum.
Hypericum humifusum is a prostrate flowering plant in the St. John's wort family Hypericaceae commonly known as trailing St John's-wort. It is found in Western Europe.
Hypericum hirsutum is a species of flowering plant in the family Hypericaceae, commonly known as hairy St John's-wort. It is found in Western Europe.
Hypericum elodes, commonly known as marsh St John's-wort, is a species of flowering plant in the St. John's wort family Hypericaceae. It is native to Western Europe.
Hypericum punctatum, the spotted St. John's wort, is a perennial herb native to North America. The yellow-flowered herb occurs throughout eastern North America into southern Canada. The process of microsporogenesis carried out by this plant is prone to errors in chromosomal segregation. It has a diploid number of 14 or 16. Insects are attracted to the plant's pollen and the hypericin in the plant's leaves is toxic to mammals.
Hypericum cuisinii is a perennial herb in the genus Hypericum, in the section Adenosepalum. The herb has pale yellow flowers and occurs in Greece and Turkey.
Hypericum canadense, known as Canadian St. Johns-wort, lesser St. John's wort, and lesser Canadian St. Johnswort, is a flowering plant in the genus Hypericum. It is a yellow-flowering annual or perennial herb native to North America and introduced to Ireland and The Netherlands. The specific epithet canadense means "Canadian".
Hypericum undulatum, the wavy St Johns Wort, is a herbaceous perennial flowering plant native to western Europe and northern Africa. The specific name undulatum is Latin, meaning "wavy" or "undulated", referring, just as the common name, to the wavy leaf margins of the herb. The plant has a diploid number of 16 or 32.
Hypericum edisonianum, known as Arcadian St. John's wort, Edison's St. John's wort, and Edison ascyrum, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to Florida.
Hypericum suffruticosum, known as pineland St. John's-wort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is native to the Southeastern United States.
Hypericum majus, the greater Canadian St. John's wort, is a perennial herb native to North America. The specific epithet majus means "larger". The plant has a diploid number of 16.
Hypericum myrtifolium, the myrtleleaf St. Johnswort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to the Southeastern United States. It was first described by Jean-Baptiste Lamarck in 1797.
Hypericum assamicum is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to India. Hypericum assamicum is one of two species of Hypericum in the section Hypericum sect. Sampsonia.
Hypericum przewalskii, commonly called Przewalski's St. John's wort, is a flowering plant in Hypericumsect. Roscyna that is native to China.
Hypericum aucheri, also known as Koramanotu in Turkish, is a herbaceous perennial flowering plant in the St. John's wort family Hypericaceae.
Hypericum harperi, the sharplobe St. Johnswort or Harper's St. John's wort, is a perennial flowering plant in the family Hypericaceae. It is an aquatic herb native to southeast North America. H. harperi has a diploid chromosome number of 24.
