AT present, durian is highly-priced in the Philippines and even in other countries.
The durian tree belongs to the family Bombacaceae. In his book, Underexploited Tropical Plants With Promising Economic Value, Dr. Roberto E. Coronel notes: "The durian was probably introduced into the Philippines during its early trading with neighboring countries. Up to now, it still grows wild in many places in Mindanao and is particularly abundant from Davao to the lake region of Agusan and the Sulu archipelago."
There are several species of durian. To those who wanted to plant durian, Dr. Pamplona recommends these high yielding durian selections: Chanee, Mon thong, Kanyao, Cadumtong, DES 916, DES 1497, and DES 806.
The durian tree is medium to large, and grows as tall as 40 meters. Grafted orchard trees, however, seldom reach a height of more than 12 meters. Trees grown from seedlings start blooming on the seventh year. Flowering in grafted trees begins on the fourth year or sooner if the trees are growing vigorously.
The durian fruit weighs from 1.5 to 2.5 kilograms. Some may weigh as much as 7-8 kilograms. The color is normally a dull olive green, but varies from a light rusty tone to a light yellowish green.
Durian is propagated by seeds and can also be grown using the branches. The seed is notoriously short-lived and is affected by high temperature. Brief exposure to direct sunlight will damage the seed. The seed loses viability in about a week even if stored in a cool place.
Experts say durians cannot be propagated by using rootings of cuttings and marcottage. Perhaps the best and the most practical method of propagation is grafting.
Large healthy seeds are planted with the flat side in well-drained soil, if possible directly in plastic bags or containers containing eight liters of soil.
Germination and subsequent growth are relatively fast, producing good-sized seedlings suitable for grafting in about two months. Young, vigorous seedlings with pencil-thick diameter near the ground are best for grafting, according to the Mindanao Baptist Rural Life Center (MBRLC) based in Kinuskusan, Bansalan, Davao del Sur.
The bud is cut off from the scionwood of a relatively young branch about as thick as a pencil. The thin slice of wood behind the bud is carefully removed so as not to pull off the base of the bud, leaving a shield of cortex containing the bud.
The rootstock cortex is carefully lifted out after tone base and two lateral incisions are made into the wood. This flap of cortex should be slightly wider than the scion, which is immediately slipped under it.
The two cambium surfaces are then pressed together. The flap of the rootstock is cut so that it slightly overlaps and covers the top of the scion shield. The graft is covered with a strip of polyethylene leaving the small bud of the scion slightly uncovered, or covered carefully and loosely.
Within 25 to 30 days, the scion - united with the stock - begins to grow. Otherwise, the stock should be re-grafted immediately before it becomes too woody.
The young bud grows rapidly after the polyethylene is loosened. A stake beside it is necessary to support and train the growing scion. The stock is gradually pruned as the scion grows and develops more foliage. Young potted plants should be properly irrigated particularly during the dry season.
Young plants in containers need to be fertilized often and lightly by hand. About 5 grams of a mineral fertilizer mixture containing 6-6-6 (never a higher analysis than 8-8-8) should be used monthly.
Durian in the nursery should not be pruned prior to trans- planting. The plant acquires a desirable pyramidal shape by itself and will gradually need more space as it grows. An 8-1 container will usually produce a plant ready for field trans- planting in 14 to 16 months.
The durian is planted in humid lowland areas below an elevation of 800 meters. It does not thrive in areas with a distinct dry season. Durian seedlings should be transplanted in rich, deep, well-drained soil.
By the way, the durian fruit is a good source of carbohydrates, fats, vitamins, and some protein. The ripe pulp is usually eaten fresh by most people. The pulp can also be made into jam, preserve (often packed like long sausages), candies and other sweets, or used as ice cream flavoring. On the other hand, the unripe or half-ripe pulp may be used in making soup.
Unknown to many, the seeds of durian are roasted, cut into slices and fried in spiced coconut oil to be eaten with rice or covered with sugar and consumed as a sweetmeat in Indonesia.