Camellias are evergreen shrubs or small trees up to 20 m (66 ft) tall. Their leaves are alternately arranged, simple, thick, serrated, and usually glossy. Their flowers are usually large and conspicuous, one to 12 cm in diameter, with five to nine petals in naturally occurring species of camellias. The colors of the flowers vary from white through pink colors to red; truly yellow flowers are found only in South China and Vietnam. Camellia flowers throughout the genus are characterized by a dense bouquet of conspicuous yellow stamens, often contrasting with the petal colors.The so-called “fruit” of camellia plants is a dry capsule, sometimes subdivided in up to five compartments, each compartment containing up to eight seeds.
The various species of camellia plants are generally well-adapted to acidic soils rich in humus, and most species do not grow well on chalky soil or other calcium-rich soils. Most species of camellias also require a large amount of water, either from natural rainfall or from irrigation, and the plants will not tolerate droughts. However, some of the more unusual camellias – typically species from karst soils in Vietnam – can grow without too much water.
Camellia plants usually have a rapid growth rate. Typically they will grow about 30 cm per year until mature – though this does vary depending on their variety and geographical location.