Gardenia is a genus of 142 species of flowering plants in the coffee family, Rubiaceae, native to the tropical and subtropical regions of Africa, southern Asia, Australasia and Oceania. The genus was named by Carl Linnaeus after Dr. Alexander Garden (1730 to 1791), a Scottish-born American naturalist. They are evergreen shrubs and small trees growing to 1 to 15 metres tall. The leaves are opposite or in whorls of three or four, 5 to 50 centimetres long and 3 to 25 centimetres broad, dark green and glossy with a leathery texture. The flowers are solitary or in small clusters, white, or pale yellow, with a tubular-based corolla with 5 to 12 lobes (petals) from 5 to 12 centimetres diameter. Flowering is from about mid-spring to mid-summer and many species are strongly scented.

Gardenia thunbergia is a beautiful flowering shrub or small tree, with showy, heavily perfumed flowers and decorative fruits. This is an evergreen shrub or small tree, 2 to 5 m in height, when planted into open ground, with a smooth, whitish, usually straight main stem up to 250 to 300 mm in diameter, and short, rigid branchlets. The leaves are glossy light green, hairless, softly to thinly leathery and conspicuously veined. The flowers are large, showy, creamy white and heavily perfumed, particularly at night. They open from elegantly furled creamy-green buds. The flowers do not turn yellow as they age on the bush. Flowers are produced abundantly during summer, peaking in late summer. The fruits do not burst or split open, or drop, and can remain on the bush for years. They are adapted to being eaten by elephants, large antelope and buffalo, and the seed coats are tough enough to pass through their digestive systems unscathed. Unless man intervenes, the seeds will not be released from the fruits and dispersed unless these animals eat them.