Home gardeners in Costa Rica who enjoy collecting rare fruits of the tropics will certainly enjoy growing mangosteen, one of the most praised and esteemed fruits on the planet.
Mangosteen (Garcinia mangostana L.) is known as mangostán in Spanish, and has been successfully grown in Costa Rica for several decades. During the 1980s, the Ministry of Agriculture’s research stations began propagating and distributing mangosteen as a new cash crop for farmers in the country. Today, it’s possible to find farmers selling their mangosteen fruits in local markets, where you can sample this tasty fruit and save the seeds for planting. Seedling trees are now available in many leading nurseries across the country.
The mangosteen fruit is easy to recognize. The round fruits, 3.5-7.5 centimeters in diameter, are dark-purple to red-purple with smooth skin. On the inside there are four to eight triangular segments of snow-white, juicy, soft flesh (actually the arils of the seeds). The fruit may have one to five fully developed seeds that cling to the flesh. The pulp is sweet with a slightly acid taste and a distinct flavor that is acclaimed as exquisitely luscious and delicious. It is hard to compare it with the flavor of any other fruit.
The mangosteen tree is six to 25 meters in height and has dark-brown or nearly black bark, with ovate-oblong, opposite leaves that are glossy, evergreen, leathery and thick.
Young leaves are rosy in color. The flowers are fleshy green with red spots on the outside and a yellowish-red tint on the inside.
The mangosteen is believed to have originated in Malaysia, and today it is commonly found in many parts of Asia. During the early 1900s, it was introduced into the New World tropics. This tree is a truly tropical species and grows only in the warmer regions of Costa Rica. It grows best in fertile, moist soils with partial shade. Full sun, drought and salt-water breezes will adversely affect these trees.
It’s curious to note that the “seeds” are actually vegetative embryos, or hypocotyl tubercles, as botanists call them. This means that each seed produces a clone of the mother tree, so there is no genetic variation. Only the largest “seeds” from each fruit should be planted, since the smaller ones often fail. The seeds are very fragile and should be planted within five days after opening the fruit.
Attempts to graft and propagate new trees by cuttings have not been successful. Be sure to plant the seeds in large containers with prepared potting soil and transplant the young seedling trees before they become rootbound.
This is important because the tap root is very delicate. It is recommended to plant them about 10 meters apart. One or two trees are sufficient for the average home orchard. Mangosteens produce their first harvest in six to 10 years, depending on fertilization.
Applications of aged compost and mulch improve the vigor and growth of these trees and shorten the time before the first harvest. New trees may produce up to 200 fruits per year, while mature trees can produce up to 500. Mangosteens are hardy trees with few insect or disease problems; however, squirrels and monkeys love them.
Recently, mangosteen juice, much like noni juice, has hit the international market via the Internet. Bottles are sold for $35 and are promoted as a cure for cancer. However, these claims may be unfounded, as little research has been done on the healing properties of the fruit, according to Dr. Ralph Moss of the Web site www.cancerdecisions.com.