An indoor orange tree, such as the Calamondin, is a type of citrus tree that can be grown indoors as a houseplant. Often referred to as a miniature orange tree, with the proper care this plant can bear fruit. Approximately an inch in diameter, these small orange-like fruits are, unfortunately, not nearly as sweet as their larger counterparts.
The calamondin orange needs a sunny window, average room temperature and nights that are about 10 degrees cooler than daytime temperatures. The plant also needs frequent misting and acidic fertilizer. The fertilizer should be applied every few weeks while the plant is flowering and the fruit is ripening. Indoor orange trees bloom between December and March, and they need to be hand-pollinated so that fruit can be set.