Hypericum perforatum, known as St. John's wort, is a flowering plant in the family Hypericaceae and the type species of the genus Hypericum.
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 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 dolabriforme, the straggling St. Johnswort or glade St. John's-wort, is a species of flowering plant in the St. John's wort family Hypericaceae native to the United States.
Hypericum hypericoides, commonly called St. Andrew's cross, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is native to the Southeastern United States, Mexico, Central America, and the Caribbean. Its preferred habitat is dry woods on acidic soil. It is a small shrub or shrublet that produces yellow flowers with four petals. There are, according to some classifications, 2 subspecies, hypericoides and multicaule. However, the later of these is usually classified as a separate species, Hypericum stragulatum.
Hypericum kalmianum, commonly called Kalm's St. Johns wort or Kalm's St. Johnswort, is a flowering plant in the St. John's wort family Hypericaceae. It is native to the Great Lakes region in the northern United States and southern Canada. Hypericum kalmianum was named after its discoverer, Swedish botanist Pehr Kalm (1715-1779).
Hypericum densiflorum, also known as bushy St. John's wort or dense St. John's wort, is a perennial herb in the flowering plant family Hypericaceae native to North America. The specific epithet densiflorum is Latin, meaning "densely flowered", referring to the many-flowered cymes.
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 prolificum, known as shrubby St. John's wort, is a deciduous shrub in the genus Hypericum. It was named for its "prolific" number of stamens.
Hypericum tenuifolium, known as Atlantic St. John's-wort and sandhill 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 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 galioides, the bedstraw St. Johnswort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to the Southeastern United States.
Hypericum tetrapetalum, the fourpetal St. Johnswort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is found in the Southeastern United States and Cuba. It was first described by Jean-Baptiste Lamarck in 1797.
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 gymnanthum, the small-flowered St. John's wort or clasping leaf St. John's wort, is a species of flowering plant in the St. John's wort family Hypericaceae native to wet woods, bogs, and ditches of the eastern United States and Guatemala. It has been introduced to Poland.
Hypericum virginicum, the marsh St. Johns-wort or Virginia marsh St. Johnswort, is a species of flowering plant in the family Hypericaceae. It is native to the central and eastern United States and eastern Canada.
Hypericum frondosum, the cedarglade St. Johnswort or golden St. John's wort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is native to the central and southeastern United States in dry, rocky habitats.
Hypericum erythreae, the Georgia St. John's-wort, sparse-leaved St. John's-wort, or grit St. Johnswort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is native to the southeastern United States in seepage bogs and roadside ditches. Its name grit St. Johnswort comes from its limited distribution, within the Altamaha Grit region of the Georgia coastal plain.
Sandhill St. John's wort is a common name for several plants and may refer to:
