Clethra is a genus of flowering shrubs or small trees described as a genus by Linnaeus in 1753. Clethra is one of two genera in the family Clethraceae (the other being Purdiaea). The species may be evergreen or deciduous, and all bear flowers in clusters (inflorescences), which correspond to racemes or panicles. The flowers are quite small, white or pinkish, and each bear 5 free petals, numerous stamens, and a 3-chambered seed capsule. The leaves, simple, ovate, and alternate or opposite, bear characteristic stellate hairs. The seeds are very small and numerous.