Direct-seeding: Direct-seeding in the field is the best propagation method if the planting locations are well prepared, weed free, and frequently tended for the first 6-12 months of growth. It eliminates any transplant trauma. In direct-seeding, an area is prepared for each planting spot, cleared of weeds, and cultivated to a depth of 50cm if the soil is compacted. Seeds are planted at a depth of 2-3 cm. Sowing several seeds at each site allows for selecting the most vigorous seedling and can prevent the necessity of reseeding. Generally 4-5 seeds are planted in situ in India so that the taproot can grow undisturbed. The drawbacks of direct-seeding include risk of predator damage (e.g., rats, pigs, cattle, etc.), lack of rains to sustain the newly germinated seeds, and the mandatory frequent maintenance that must be done to ensure weeds do not overcome the seedlings.

Seedling transplanting: Jackfruit seedlings are very easy to grow. Seedlings develop very quickly, reaching 25cm in height within 3-4 months. Seeds are cross-pollinated and therefore not true-to-type, so grafting known varieties onto rootstocks is often done, especially for commercial production where a uniform product with the best market qualities is important. Because the seeds are large and grow quickly and their root systems are sensitive to damage during transplanting, direct-seeding in the field can give the best results. Fieldsown seedlings can be top-worked (grafted) with select varieties once they are established.

Soaking one-month-old seedlings in a gibberellic acid solution (25-200 ppm) prior to field planting enhances shoot growth. Gibberellic acid spray and paste increase root growth. Seedlings are sensitive to root injury and should be moved within the nursery once or twice a month to prevent the roots from penetrating into the ground. Excess shoots should be removed just before or after transplanting and the leaves trimmed to reduce transpiration.

The seedlings should be moved into the field when no more than 4 leaves have appeared. If seedlings are grown in the nursery, it is crucial to outplant them before they become root-bound. Transplanting seedlings when they have just filled out their growing container will ensure minimal trauma to the root system.

Seedlings have reached target size when approximately 20cm in height and have a stem diameter of 9mm. Seedlings should be transplanted to the field at approx. 1 year old at the start of the rainy season, with a spacing of 8-12m (100-120 trees/ha). In ideal conditions, field survival of about 90% can be expected. A more advanced seedling, with its long and delicate tap root is very difficult to transplant successfully.

Jackfruit seedlings in plastic container or in polyethylene bags

In plantations, the plants are set 9-12m apart in fertile soil using square system accomodating 123 to 70 plants per hectare. On average soil, plants may be planted at 11m apart. Higher planting density is practised in lighter and poorer soils but not on fertile soils because of top crowding of trees.

For planting jackfruit, 1m 3 holes are dug at least 10 days before planting. Each planting hole is placed with 30 kg well-rotted farmyard manure and 500 g of TSP mixed with top soil of each hole and the hole is refilled during planting. After planting the soil around the plant is firmed to avoid water-logging in holes during rainy season which is detrimental to young plants. The taproot should not be disturbed while planting to avoid plant damage. Field planting should commence at the beginning of rainy season. Dry weather may lead to the death of the plants. Young plantings require protection from sunscald and from grazing animals, hares, deer, etc. In colder regions, protection against frost assured survival and growth the plants. Frequent weeding and mulching are essential for achieving normal plant growth.

Budgrafted jackfruit plant		Jackfruit tree in the field

Jackfruit is a rapid grower, reaching a height of 3 m and canopy diameter of 2m in 2 years. Height growth for the first few years is about 1.5m/yr, slowing to 36-60 cm/yr (Acedo 1992). A 20-year-old tree can reach 17.5m (57 ft) in height and 20 cm in trunk diameter (Morton 1987). While trees can live to 100 years of age, their removal and replacement in Thailand plantations after 20 years of growth suggests a significant decrease in productivity with age. That is why, it is recommended that alternate rows be planted every 10 years so that 20-year-old trees may be routinely removed from the plantation and replaced by a new generation.

Intercropping: During the early years, jackfruit can be successfully intercropped with a number of short-term crops such as legumes, vegetables, and banana. The intercrop makes use of the unproductive space available in the early years and gives an income before the jackfruit trees come into production. As the trees grow closer, the crops grown among the trees can be replaced by a permanent ground cover. Perennial crops such as durian, coffee, coconut and citrus can be grown together with jackfruit, given wider spacing between jackfruit trees to allow sufficient space for the other crop trees. In young jackfruit orchards, where there is ample space between trees, annual crops can be grown. One or two trees growing in mixed homegardens together with numerous other tree crops is also very common.

Jackfruit intercropped with dragon fruits

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