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, with glossy leaves and solitary, brilliant red flowers in summer and autumn. The five-petaled flowers are 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 to pink, orange, peach, yellow and purple. Some have double flowers. 

The flower is additionally used in hair care as a preparation. It is also used to shine shoes in certain parts of India. It can also be used as a pH indicator. When used, the flower turns acidic solutions to a dark pink or magenta color and basic solutions to green. 

The leaves are often lobed and may be smooth or covered in trichomes (plant hairs). The flowers can be borne singly or in clusters, and the flowers of many species last only a single day. An epicalyx (whorl of leaflike bracts that surrounds the sepals) is particularly common, and the stamens are typically fused into a tube. Members of the genus characteristically have spiny pollen, and their fruits are capsules.

The shrub is fast-growing and can add up to 24 inches per year, eventually reaching heights of up 15 feet when growing under the ideal conditions.