is an evergreen flowering plant of the coffee family Rubiaceae It originated in Asia and is most commonly found growing wild in Vietnam, Southern China, Korea, Taiwan, Japan, Myanmar, India and Bangladesh. Wild plants range from 30 cm to 3 m high and have a rounded habit with very dense branches with opposite leaves, lanceolate-oblong, leathery or gathered in groups on the same node and by a dark green, shiny and slightly waxy surface and prominent veins.
With its shiny green leaves and heavily fragrant white summer flowers, it is widely used in gardens in warm temperate and subtropical climates, and as a houseplant in temperate regions. It has been in cultivation in China for at least a thousand years, and was introduced to English gardens in the mid-18th century. Many varieties have been bred for horticulture, with low-growing, and large, and long-flowering forms.
Gardenia is a shrub that ranges from 30 cm to 3 metres (1-10 ft) high in the wild, with cylindrical to flat branches that are furry at first becoming smooth. The leaves are arranged oppositely—or rarely in groups of three—along the branches. They are either subsessile or on short 0.5-1 cm long petioles. The leaves themselves are 3-25 cm long by 1.5-8 cm wide and can be oblong-lanceolate, obovate-oblong, obovate, oblanceolate, or elliptic in shape. Their upper surface is smooth and shiny, or slightly furry along the primary veins, while the undersurface is slightly furry to smooth. Each leaf has 8 to 15 pairs of secondary veins. The flowers are solitary and terminal (arising from the ends of stems).
The white flowers have a matte texture, in contrast to the glossy leaves. They gradually take on a creamy yellow color and a waxy surface. They can be quite large, up to 10 cm (4 in) in diameter, loosely funnel-shaped, and double in form. Blooming in summer and autumn, they are among the most strongly fragrant of all flowers. They are followed by small, oval fruit.
Gardenia is used within traditional Chinese medicine to "drain fire" and treat certain febrile conditions, i.e. have an anti-inflammatory and antipyretic effect.
The fruits are used to make medicine. Gardenia is used for swelling (inflammation), liver disorders, diabetes, and other conditions, but there is no good scientific evidence to support these uses. In food, gardenia is used as a yellow food colorant.
Shishihakuhito is a Chinese herbal medicine mainly composed of gardenia fruit, used to treat atopic dermatitis.