A familiar houseplant and indoor bonsai subject in cool climes, Carissa macrocarpa is indigenous to the coastal region of Natal, South Africa—hence the common name. A vigorous, spreading, woody shrub, it grows up to 18 feet tall, produces handsome, broad, evergreen foliage, and equips its branches with stout Y-shaped spines. Its two-inch-long tubular flowers are white and sweetly fragrant. The oval fruit of the Natal plum can grow up to two inches long and 1¼ inches wide. As it ripens, the skin turns a bright magenta red. The flesh is tender, very juicy, strawberry-colored, and flavored with flecks of milky sap. The small seeds are unobjectionable and are usually eaten. When fully ripe, the protein-rich fruit can be consumed out of hand or made into jellies, syrups, gelatin-based desserts, pies, and tarts.

The Natal plum is generally drought-resistant, but don’t allow the soil to dry out too much between waterings. Provide a sunny exposure and give your plant a summer vacation outdoors, if possible. Fertilize it regularly with any all-purpose water-soluble plant food. Cuttings are terribly difficult to root, so starting from seed is the best method of propagation.

source : www.bbg.org