Image: Aripai Leangphet/Shutterstock.comRambutan trees can grow to a height of 50 to 80 feet with a straight trunk that can reach up to 24 inches in diameter with dense canopy. The fruit, also called rambutan, is oval in shape and varies in color from pinkish-red or dark purple to orange-yellow, though it is most recognized by its vibrant pink color. The fruit is native to Malaysia and covered in spiny hairs, hence its name from the Malay word for hair, rambut. Rambutan peels much like a hard-boiled egg—break the outer shell and peel back the spiny outer covering to reveal the aril (the fruit itself ) inside. The aril contains a small, bitter tasting seed that is typically discarded and not eaten with the fruit.
Types & Varieties Detailed information on rambutan is difficult to come by. There appear to be two main types of rambutan, red and yellow. Red varieties are medium in size and ripen in September or October; the aril is white, dry, and sweet. The yellow varieties are somewhat smaller in size and ripen in October; arils are white, juicy, and sweet. Red varieties include Queen Zaida, Princess Caroline, Roxas, Laurel, Sr. and Ponderosa Ferreras. Yellow varieties include Quezon, Zamora, Quirino, Santo Tomas, and Victoria. Size of the fruit, sweet/tartness, and flesh color differ by variety. CULTIVATION Rambutan trees prefer well-drained soil, warm temperatures, high humidity, and plenty of rainfall. Trees should be placed 30 to 40 feet apart as overcrowding will affecting production. Early pruning encourages trees to grow tall and straight, and removal of twigs after harvest will stimulate new growth. Remove dead branches regularly and mulch during dry periods. Fertilizer should be applied after fruit set (or flower budding), immediately after harvest, then again a few months later.
Pests & Diseases
Birds and flying foxes (fruit-eating bats) are the biggest dangers to rambutan. They feed on crops, severely decreasing yields. Flying foxes are a problem in Australia, Indonesia, and mainland Asia where they roost in camps or communal sites. Like other species of bats, they hang upside down in trees, but this particular species eats only fruit.
Loopers are green with white stripes and eat irregular holes in leaves. Red-banded thrips damage leaves with silver trails and dark colored spots.
Stem-end rot, indicated by slight shriveling at the stem, is caused by bacteria and fungi and occurs in the grove during harvest. Unfortunately, it does not become apparent until after fruit is shipped. It does little damage but is still a concern during handling. Anthracnose attacks leaves, branches, and flowers. Round, grey areas occur on leaves and outbreaks typically occur after warm, wet weather.
Storage & Packaging
Rambutan does not ripen off the tree, rendering ethylene treatment unnecessary. Optimal storage temperatures run from 50 to 54°F depending on cultivar, and fruit can be stored for 12 to 14 days.
High relative humidity (90 to 95%) is ideal to minimize moisture loss and browning of the skin. Controlled atmosphere of 3 to 5% oxygen and 7 to 12% carbon dioxide increases storage life to 4 weeks.
References: Australia Dept. of Primary Industry, Fisheries & Mines, Purdue University; UC Davis Postharvest Technology Center.
GRADES & GOOD ARRIVAL
Currently, there are no good arrival guidelines specific to United States or Canada for rambutan.
References: DRC, PACA, USDA.
Rambutan Terminal Market Pricing: 15 lb. RPCs