Almost everywhere in Davao, one can see durian piled up in stacks, emitting that strange acrid smell. It's durian season once again in the Philippines' fruit basket.

A friend once told us that people working in the Manila Domestic Airport would know a flight coming from Davao by the smell of durian that reeks out from the plane even before it unloads its cargoes.

Durian, that rich tasting, pulpy, stomach-filling fruit, which has been described as "mixture of old cheese and onions flavored with turpentine", is one of Davao's most celebrated "pasalubong" export to the rest of the country.

This thorny fruit has been known to be an aphrodisiac as it supposedly sends a rush of erotic passion to those who feast on it.

What's exactly a durian? Durian, which scientific name is Durio zibethinus Murray, is a tropical fruit and regarded as an important fruit crop in Malaysia, Indonesia, Thailand and the Philippines (specifically here in Mindanao).

The fruit weighs from anywhere from one to three kilograms. The color is normally a "dull olive green" though it varies from a "light rusty tone to a light yellowish green".

The durian fruit is considered a good source of carbohydrates, fats, vitamins and some protein. There are at least five species of durian. Several bear edible fruits that are said to taste as good as, or better than, the common durian.

The species are Durio zibenthinus, Durio kutejensis, Durio oxlevanus, Durio graveolens and Durio dulcis.

The odor is said to vary among the species. Some have only slight odor such as the D. graveolens, which produces an almost odorless fruit, while the D. kutejensis has mild, inoffensive odor. Its tree belongs to the Bombacaceae family.

It can grow from medium to large, and as high as forty meters. However, grafted trees barely reach the height of more than twelve meters. The blooming of the seedling trees start on the seventh year while flowering in the grafted trees begins on the fourth year or even sooner if the trees are growing robustly.

Durian is propagated by seeds and can only be grown using its branches. It can not be propagated using rootings or marcottage. The seed is known to be short lived and is easily affected by high temperature.

Exposing it even briefly to direct sunlight will impair it. The seed loses viability in about a week even if stored in a cool place. Grafting is the most practical method of propagating durian.

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 growth are relatively fast, producing seedlings suitable for grafting in about 2 months.

Young seedlings, pencil-thick in diameter near the ground, are best suitable for grafting. The bud or sprout is sliced off from the scionwood of a young branch.

The thin slab of wood behind the bud is carefully removed so as not to pull off the base of the bud, leaving a shield of tree bark containing the bud. The taproot cortex is carefully lifted out after the tone base and two lateral incisions are made into the wood. The flap of the cortex should be slightly uncovered, or covered carefully and loosely.

No further than 25 to 30 days, the scion-united with the stock-begins to grow. To prevent the stock from becoming too woody, it should be re-grafted immediately.

The young bud grows instantly after the plastic bag is loosened. In order to support the growing scion, a stick is necessary to support and train the growing plant. The stock is gradually pruned as the plant grows and develops more foliage.

Young potted plants should be properly irrigated especially during the dry season. The young plants in containers need to be fertilized often and lightly by hand. Those contained in nurseries should not be pruned before transplanting it.

The growing plant naturally acquires a pyramidal shape, gradually needing more space as it grows. The plant will be then ready for field transplanting in 14 to 16 months.

Humid lowland areas with an elevation below 800 meters are the most conducive to planting durian as durian seedlings should be transplanted in rich, deep well-drained soil.

It does not normally grow in areas with a distinct dry season. The land is preferably plowed and planted to other crops prior to transplanting. Weedy and idle land should be plowed and harrowed at least twice to eliminate the weeds and loosen the soil.

A hole should be dug for each plant, half of the hole refilled with mixed soil consisting of 1/3 animal manure, 1/3 sand and 1/3 ordinary soil.

Before placing the seedling in the hole, the plastic bag containing the seedling and the soil should be removed first using a knife or blade. Gradually, the seedling is covered with pulverized top soil as it is set inside the hole. It must be watered regularly and sprayed with pesticides to get rid of insects. The amount and kind of fertilizer to use depends on the fertility of the soil.

Its unusual flavor and exotic appearance have entranced travelers from all over.

In 1599, Linschott, a traveler, said that the durian "is such an excellent taste that it surpasses in flavor all the other fruits in the world."

While a world famous historian Dr. Paludanus remarked that "to those not used to this fruit, it seems at first to smell like rotten onion but immediately after they have tasted it they prefer it to all other food."

In addition, British naturalist Alfred Russell Wallace, after visiting the interior of Borneo in 1856, wrote ecstatically: "It was worth a journey to the East, if only to taste of its fruit."

Today, most especially during the celebration of the "Kadayawan sa Dabaw", the durian once reigns as "master of the pasalubong crates". Anywhere from Magsaysay Park, Madrazo Fruits Stand, Anda Fruit Stand, to just about every street corner in Davao, durian is king.