A genus of flowering plants in the family Theaceae. They are native to eastern and southern Asia, from the Himalaya east to Korea and Indonesia. There are 100–250 described species, with some controversy over the exact number.
They are evergreen shrubs and small trees 2–20 m tall. The leaves are alternately arranged, simple, thick, serrated, usually glossy, and 3–17 cm long. The flowers are large and conspicuous, 1–12 cm diameter, with (in natural conditions) 5–9 petals; colour varies from white to pink and red, and yellow in a few species. The fruit is a dry capsule, sometimes subdivided into up to 5 compartments, each compartment containing up to 8 seeds.
Many other camellias are grown as ornamental plants for their flowers; about 3,000 cultivars and hybrids have been selected, many with double flowers. The Japanese Camellia – often simply called "the camellia" – is the most prominent species in cultivation, with over 2,000 named cultivars.