Hypericum perforatum, commonly known as St John's wort, is a flowering plant in the family Hypericaceae and the type species of the genus Hypericum. It is a perennial that grows up to one metre tall, with many yellow flowers that have conspicuous black glands around their edges, long stamens, and three pistils. Probably a hybrid between close relatives H. attenuatum and H. maculatum that originated in Siberia, the species now has a cosmopolitan distribution. It is native to temperate regions across Eurasia and North Africa, and has been introduced to East Asia, Australia, New Zealand, and parts of North and South America. In many areas where it is not native, H. perforatum is considered a noxious weed. It densely covers open areas to the exclusion of native plants, and is poor grazing material. As such, methods for biocontrol have been introduced in an attempt to slow or reverse the spread of the species.
Hypericum calycinum is a species of prostrate or low-growing shrub in the flowering plant family Hypericaceae. Widely cultivated for its large yellow flowers, its names as a garden plant include Rose-of-Sharon in Britain and Australia, and Aaron's beard, great St-John's wort, creeping St. John's wort and Jerusalem star. Grown in Mediterranean climates, widely spread in the Strandja Mountains along the Bulgarian and Turkish Black Sea coast.
Hypericaceae is a plant family in the order Malpighiales, comprising six to nine genera and up to 700 species, and commonly known as the St. John's wort family. Members are found throughout the world apart from extremely cold or dry habitats. Hypericum and Triadenum occur in temperate regions but other genera are mostly tropical.
Serratula tinctoria, commonly known as dyer's plumeless saw-wort or saw-wort, is a species of flowering plant in the family Asteraceae.
Packera obovata, commonly known as roundleaf ragwort, spoon-leaved ragwort, roundleaf groundsel, or squaw-weed, is an erect perennial herb in the Asteraceae (aster) family native to eastern North America. It was previously called Senecio obovatus. Basal and lower leaves are obovate with toothed margins, while upper leaves are pinnately divided. The ray flowers are yellow and the disk flowers orange-yellow, the inflorescences being held well above the foliage.
Blackstonia perfoliata or more commonly known as the yellow-wort is a species of flowering plant in the family Gentianaceae found around the Mediterranean Basin, but extending into northwestern Europe.
Mirabilis nyctaginea is a species of flowering plant in the four o'clock family known by several common names, including wild four o'clock, heartleaf four o'clock, and heartleaf umbrella wort.
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 forrestii is a species of flowering plant in the family Hypericaceae native to China and Myanmar. It is known as Forrest's tutsan and Forrest's St. John's wort. It was named in honour of the Scottish botanist George Forrest (1873-1932), who was the first westerner to discover it. The species has gained the Royal Horticultural Society's Award of Garden Merit.
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 sphaerocarpum, the roundseed St. Johnswort or barrens St. John's wort, is a species of flowering plant in the St. John's wort family. It is native to the Eastern United States where it is primarily found in the Midwest and Mid-South as well as Ontario, Canada. Its preferred habitat is dry, calcareous glades and prairies.
Hypericum boreale, also known as northern St. John's-wort, is a short-lived perennial species of flowering plant in the family Hypericaceae, section Trigynobrathys.
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 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 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 lancasteri, known as Lancaster's St. John's wort or as zhan e jin si tao in Chinese, is a species of flowering plant in the St. John's wort family Hypericaceae. The species has been awarded the Royal Horticultural Society's Award of Garden Merit.
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.
