Camellia japonica ( often simply called Camellia ) is the most prominent species in cultivation , with over 2,000 named cultivars ; next are C. reticulata , with over 400 named cultivars , and C. sasanqua , with over 300 named cultivars . The Japanese Camellia -- often simply called `` the camellia '' -- is the most prominent species in cultivation , with over 2,000 named cultivars . Next are C. reticulata with over 400 named cultivars , and the Christmas Camellia with over 300 named cultivars .