Culture
Winter hardy to USDA Zones 9-11 where this small citrus tree will grow well in sandy, neutral, well-drained soils in full sun to light shade. Best performance occurs in full sun. Provide consistent and regular watering. Avoid wet poorly drained soils. Plants will struggle with temperatures below 40°F, and are intolerant of frost. North of USDA Zone 9, it may be grown in a container as a houseplant. Use an all purpose, loose, well-drained potting mix. Set container outdoors in late spring in full sun in a location protected from wind. Bring container indoors in fall for overwintering in a cool but bright sunny southern window. In winter, mist plants with water almost daily or use a humidifier (plants love humid environments). Indoor plants may produce some fruit during the period of fall to spring. Propagate by grafting (plants are seedless).
Noteworthy Characteristics
Citrus reticulata is commonly called mandarin orange. It is native to Southeast Asia. It is a rounded, usually thorny, evergreen shrub or small tree that grows to 15-25’ tall and produces fruit (to 3” diameter) resembling oranges. Mandarin oranges have been in cultivation since 2000 B. C. Ovate to lanceolate leaves (to 1 1/2” long) are evergreen. Fragrant white flowers bloom in the leaf axils in spring. It is sometimes commonly called Christmas orange because of its popularity over the Christmas holidays.
The genus name Citrus is from classical Latin.
Specific epithet means netted.
‘Clementine’ is a variety of mandarin orange that reportedly originated as a chance hybrid in the Algerian garden of Father Clement Rodier in 1902, although some authorities claim it originated much earlier in China and simply spread over time to the Mediterranean area. It is the smallest of the mandarins, producing sweet, seedless, spherical to elliptic fruit (to 2 3/8” diameter) with a loose, deep orange-red peel during the period of fall to spring. Cultivar name honors Father Clement Rodier.
Problems
Susceptible to anthracnose, scab, sooty mold, greasy spot, canker and gummosis. Potential insect pests include aphids, thrips, cutworms, plant bugs, weevils, leafrollers, mealybugs, scales and whiteflys. Watch for mites. Leaf drop indoors may mean soil is too wet or too dry.
Uses
Excellent small tree for commercial fruit production, home gardens or houseplant. Where winter hardy, it is ornamentally attractive around homes or patios. May be grown as a houseplant.