Citrus reticulata, or Mandarin Orange, is a small spiny tree that is native to S.E. Asia. The lanceolate to ovate-lanceolate leaves are dark green and will reach up to 1½ inches (3.7 cm) long by half as wide. Spines will reach up to 2 inches (5 cm) long and are very rigid and sharp. They are very easy to grow and do very well in containers. Our trees, at 8 years old, are 7 feet (2 m) tall and produce quite a lot of fruit. Trees are hardy outside in USDA zones 9-12.
Blooming Our trees in the greenhouse, plants have 2 flushes of flowers: one in the spring and the other in the fall. The white fragrant flowers are followed by up to 3 inch (8 cm) fruits with a sweet flavor and very thin skin.
Culture: Citrus reticulata need full sun to partial shade with a well-drained soil mix. In the greenhouse, we a soil mix consisting of equal parts of peat, loam and sand. To this mix we add 1 cup of 14-14-14 osmocote slow release fertilizer to each .01 cubic yards. The plants are well watered and allowed to dry slightly before watering again. They are fertilized monthly with a 20-20-20 fertilizer. During the winter months, the temperature is dropped to 50° F (10° C) and water is somewhat restricted. They need very little trimming.
Propagation: Citrus reticulata is very easy to grow from seed. Fresh seed germinate in 30-60 days at 70° F (21° C).
Citrus reticulata was featured as Plant of the Week November 5-11, 2004.
Guide to Past Plants-of-the-Week:
Cal's Plant of the Week was provided as a service by the University of Oklahoma Department of Microbiology & Plant Biology and specifically Cal Lemke, who used to be OU's botany greenhouse grower and an avid gardener at home as well. If the above links don't work, then try the overview site. You may also like to look at the thumbnail index. ©1998-2012 All rights reserved.