The inflorescences are formed on the trunk, branches or twigs (caulifloria).
Jackfruit trees are monoecious, having both female and male flowers on a tree.
The inflorescences are pedunculated, cylindrical to ellipsoidal or pear-shaped, to about 10–12 cm (3 ¹⁵⁄₁₆–4 ³⁄₄ inches) long and 5–7 cm (2–3 inches) wide.
Inflorescences are initially completely enveloped in egg-shaped cover sheets which rapidly slough off.

The flowers are small, sitting on a fleshy rachis.
The male flowers are greenish, some flowers are sterile.
The male flowers are hairy and the perianth ends with two 1 to 1.5 mm (³⁄₆₄ to ¹⁄₁₆ in) membrane.
The individual and prominent stamens are straight with yellow, roundish anthers.
After the pollen distribution, the stamens become ash-gray and fall off after a few days.
Later all the male inflorescences also fall off.
The greenish female flowers, with hairy and tubular perianth, have a fleshy flower-like base.
The female flowers contain an ovary with a broad, capitate or rarely bilobed scar.
The blooming time ranges from December until February or March.

The ellipsoidal to roundish fruit is a multiple fruit formed from the fusion of the ovaries of multiple flowers.
The fruits grow on a long and thick stem on the trunk.
They vary in size and ripen from an initially yellowish-greenish to yellow, and then at maturity to yellowish-brown.
They possess a hard, gummy shell with small pimples surrounded with hard, hexagonal tubercles.
The large and variously shaped fruit have a length of 30 to 100 cm (10 to 40 inches) and a diameter of 15 to 50 cm (6 to 20 inches) and can weigh 10–25 kg (22–55 pounds) or more.

The fruits consist of a fibrous, whitish core (rachis) about 5–10 cm (2–4 inches) thick.
Radiating from this are many 10-centimeter-long (4 in) individual fruits.
They are elliptical to egg-shaped, light brownish achenes with a length of about 3 cm (1 ¹⁄₈ inches) and a diameter of 1.5 to 2 cm (⁹⁄₁₆ to ¹³⁄₁₆ inch).

There may be about 100–500 seeds per fruit.
The seed coat consists of a thin, waxy, parchment-like and easily removable testa (husk) and a brownish, membranous tegmen.
The cotyledons are usually unequal in size, and the endosperm is minimally present.
An average fruit consists of 27% edible seed coat, 15% edible seeds, 20% white pulp (undeveloped perianth, rags) and bark and 10% core.

The fruit matures during the rainy season from July to August.
The bean-shaped achenes of the jackfruit are coated with a firm yellowish aril (seed coat, flesh), which has an intense sweet taste at maturity of the fruit.
The pulp is enveloped by many narrow strands of fiber (undeveloped perianth), which run between the hard shell and the core of the fruit and are firmly attached to it.
When pruned, the inner part (core) secretes a sticky, milky liquid, which can hardly be removed from the skin, even with soap and water.
To clean the hands after "unwinding" the pulp an oil or other solvent is used.
For example, street vendors in Tanzania, who sell the fruit in small segments, provide small bowls of kerosene for their customers to cleanse their sticky fingers.
When fully ripe, jackfruit has a strong pleasant aroma, the pulp of the opened fruit resembles the odor of pineapple and banana.
The inflorescences are formed on the trunk, branches or twigs (caulifloria). Jackfruit trees are monoecious, having both female and male flowers on a tree. The inflorescences are pedunculated, cylindrical to ellipsoidal or pear-shaped, to about 10–12 cm (3 ¹⁵⁄₁₆–4 ³⁄₄ inches) long and 5–7 cm (2–3 inches) wide. Inflorescences are initially completely enveloped in egg-shaped cover sheets which rapidly slough off.
The flowers are small, sitting on a fleshy rachis. The male flowers are greenish, some flowers are sterile. The male flowers are hairy and the perianth ends with two 1 to 1.5 mm (³⁄₆₄ to ¹⁄₁₆ in) membrane. The individual and prominent stamens are straight with yellow, roundish anthers. After the pollen distribution, the stamens become ash-gray and fall off after a few days. Later all the male inflorescences also fall off. The greenish female flowers, with hairy and tubular perianth, have a fleshy flower-like base. The female flowers contain an ovary with a broad, capitate or rarely bilobed scar. The blooming time ranges from December until February or March.
The ellipsoidal to roundish fruit is a multiple fruit formed from the fusion of the ovaries of multiple flowers. The fruits grow on a long and thick stem on the trunk. They vary in size and ripen from an initially yellowish-greenish to yellow, and then at maturity to yellowish-brown. They possess a hard, gummy shell with small pimples surrounded with hard, hexagonal tubercles. The large and variously shaped fruit have a length of 30 to 100 cm (10 to 40 inches) and a diameter of 15 to 50 cm (6 to 20 inches) and can weigh 10–25 kg (22–55 pounds) or more.
The fruits consist of a fibrous, whitish core (rachis) about 5–10 cm (2–4 inches) thick. Radiating from this are many 10-centimeter-long (4 in) individual fruits. They are elliptical to egg-shaped, light brownish achenes with a length of about 3 cm (1 ¹⁄₈ inches) and a diameter of 1.5 to 2 cm (⁹⁄₁₆ to ¹³⁄₁₆ inch).
There may be about 100–500 seeds per fruit. The seed coat consists of a thin, waxy, parchment-like and easily removable testa (husk) and a brownish, membranous tegmen. The cotyledons are usually unequal in size, and the endosperm is minimally present. An average fruit consists of 27% edible seed coat, 15% edible seeds, 20% white pulp (undeveloped perianth, rags) and bark and 10% core.
The fruit matures during the rainy season from July to August. The bean-shaped achenes of the jackfruit are coated with a firm yellowish aril (seed coat, flesh), which has an intense sweet taste at maturity of the fruit. The pulp is enveloped by many narrow strands of fiber (undeveloped perianth), which run between the hard shell and the core of the fruit and are firmly attached to it. When pruned, the inner part (core) secretes a sticky, milky liquid, which can hardly be removed from the skin, even with soap and water. To clean the hands after "unwinding" the pulp an oil or other solvent is used. For example, street vendors in Tanzania, who sell the fruit in small segments, provide small bowls of kerosene for their customers to cleanse their sticky fingers. When fully ripe, jackfruit has a strong pleasant aroma, the pulp of the opened fruit resembles the odor of pineapple and banana.
Jackfruit