Hibiscus × rosa-sinensis, known colloquially as Chinese hibiscus, China rose, Hawaiian hibiscus, rose mallow and shoeblack plant, is a cultigen of tropical hibiscus, a flowering plant in the Hibisceae tribe and Hibiscus genus of the family Malvaceae. It is an artificial hybrid created in cultivation in pre-European times by Polynesians in the west Pacific from the species Hibiscus cooperi and H. kaute (native to Vanuatu and the French Polynesia, respectively). It is widely cultivated as an ornamental plant in the tropics and subtropics. The hibiscus is the national flower of Malaysia, where it holds official status, and is also considered the unofficial national flower of Haiti.

Hibiscus × rosa-sinensis is a bushy, evergreen shrub or small tree growing 2.5–5 m (8–16 ft) tall and 1.5–3 m (5–10 ft) wide. The plant has a branched taproot. Its stem is aerial, erect, bark is light-grey, green easy to peel and smooth cylindrical, and branched.

Its leaves are simple and petiolate, with alternate phyllotaxy. The leaf shape is ovate while the tip is acute, and the margin is serrated. Venation is unicostate reticulate, meaning the leaves' veins are branched or divergent. Their surfaces are glossy. Free lateral stipules are present.^{[citation needed]}

Its flowers bloom in summer and autumn. They are solitary (axillary) and symmetrical. They are typically red, with five petals 10 cm (4 in) in diameter, with prominent orange-tipped red anthers. Cultivars and hybrids have flowers in a variety of colors as well as red: white, pink, orange, peach, yellow, blue, and purple. Some plants have double flowers.

At the bottom of every hibiscus bud is the calyx, which is green in color. The pointed ends of the calyx are called the sepals. When the hibiscus begins to bloom, the flower's petals begin to grow.^{[citation needed]}

Each hibiscus flower has both male and female parts. The ovary and other female parts of the flower lie in the main structure of the hibiscus: the pistil, which is long and tubular. The five "hairy" spots at the top of the pistil make up the stigma, which is where pollen is collected. In the middle of the pistil is the style, which is the tube down which pollen travels to the ovary. The ovary lies at the bottom of the blossom, and each hibiscus has only one superior ovary. The male part of the flower, called the stamen, consists of stem-like filaments and anthers. Each filament ends with the pollen-producing anther.^{[citation needed]}

Hibiscus × rosa-sinensis was first described as a species in 1753 by Carl Linnaeus in Species Plantarum. His description was based on specimens with double bright red flowers in cultivation in the Indian subcontinent and Indonesia. The specific epithet rosa-sinensis literally means "rose of China", although the plant is not closely related to true roses, nor is it from China. The genus Hibiscus is in the tribe Hibisceae and the subfamily Malvoideae of the family Malvaceae.

Hibiscus × rosa-sinensis is one of many plants with a genetic characteristic known as polyploidy, a condition in which there are more than two complete sets of chromosomes. A result of polyploidy is that the phenotype of a plant's offspring may be quite different from the parent plant, or indeed any ancestor, essentially allowing possibly random expression of any (or all) of the characteristics of previous generations. Because of this characteristic, H. × rosa-sinensis has become popular with hobbyists who cross and recross varieties, creating new varieties. Competitions are held to exhibit and judge the many resulting new seedlings and often strikingly unique flowers.^{[citation needed]}