Germination temperature
Tropical warmth; seedlings are damaged by temperatures near 0 °C (32 °F).
Fruit tree growing guide
Jackfruit is a large tropical evergreen tree that grows easily from fresh seed. The seed dies when it dries out, so sow it within days of harvest and move seedlings young, before the taproot gets long.
Tropical warmth; seedlings are damaged by temperatures near 0 °C (32 °F).
Shallow: lay the large seed flat and cover it with a thin layer of mix, about its own thickness.
A few weeks in warm, moist conditions when the seed is fresh.
Bright light or light shade for seedlings; full sun for trees.
Wash off the pulp and sow fresh. Never dry the seed.
Sow in deep pots or bags and plant out young, or sow where the tree will grow.
Jackfruit seed is recalcitrant: it cannot survive drying and stays alive only briefly at room conditions (UF/IFAS says up to about 30 days). Wash the slippery sheath off each seed, keep it moist and sow as soon as possible. Take seed from healthy, high-yielding trees.
Not needed. The seed coat is thin and absorbs water readily.
Not needed. This is a tropical tree; cold storage damages the seed.
Not needed for fresh seed. Do not leave seed soaking for long or let it lie in a dry place.
Germinate in tropical warmth. The tree grows from sea level to about 1,200-1,600 m and suffers leaf damage at 0 °C (32 °F), so in cool climates keep pots indoors or under glass.
Lay the seed flat and cover it with a thin layer of mix, roughly its own thickness. Very deep sowing slows emergence.
Use deep containers or polybags so the taproot can grow straight down, filled with a free-draining mix of loam and well-rotted compost. Trees prefer deep, well-drained loam with pH 5-7.5.
Keep the mix evenly moist but never waterlogged. Seedlings and trees decline quickly in wet soil; UF/IFAS reports trees dying after only 2-3 days of waterlogging.
Keep trays in bright, partly shaded light until the first leaves harden, then give more sun.
Fresh seed usually emerges within a few weeks in warmth. Seed that has dried out often fails completely.
Plant seedlings out while they are young and before roots circle the container; a damaged or bent taproot sets the tree back. TNAU plants in June-December into 1 x 1 x 1 m pits filled with topsoil, 10 kg farmyard manure and 1 kg neem cake, spaced 8 x 8 m.
Water about once a week until established, then as needed. Mulch the root zone, shade young plants from harsh sun in their first hot season and protect them from grazing animals.
Seedlings vary in fruit quality. For a named variety, use the seedling as a rootstock: TNAU cleft-grafts in July-August onto 4-month-old seedlings.
Cause: seed dried out or was stored too long. Fix: sow within days of taking it from the fruit and keep it moist from fruit to pot.
Cause: root rot in waterlogged or poorly drained soil. Fix: plant on a well-drained site or a raised mound and never let water stand around the trunk.
Cause: Rhizopus rot. Fix: remove fallen and infected spikes and fruit; TNAU sprays 1% Bordeaux mixture or copper oxychloride three times at 15-day intervals.
Cause: fruit borer. Fix: remove and destroy damaged fruit and keep the tree clean; seek local advice on approved sprays if damage is heavy.
Cause: spittle bug, scales or mealybugs. Fix: prune out heavily infested shoots and control early before colonies build up.
Jackfruit needs warm, frost-free conditions and good rainfall (roughly 1,000-2,400 mm a year) or irrigation. It suits the plains and hills of South India up to about 1,200 m.
Trees become large: allow 7.5-9 m (25-30 ft) from buildings and other trees, or about 6 m with regular pruning.
Apply farmyard manure and a balanced fertiliser in two splits, May-June and September-October, increasing the amount each year until the tree is about six years old.
Fruit matures 150-180 days after flowering. Ripe fruit turns from green to light green or yellowish brown, the spines flatten, it gives off a strong aroma and sounds hollow when tapped.
Sow jackfruit seed fresh in deep pots for a strong, straight-rooted young tree.
Only briefly and only moist. The seed dies when it dries out and keeps at most a few weeks at room conditions, so sow it as soon as you can.
Usually from the 3rd-4th year in warm, well-tended conditions, but up to about 8 years in Tamil Nadu field conditions. Grafted trees bear earlier and true to variety.
Not outdoors. No variety is frost-hardy; leaves are damaged at 0 °C and trees die at about -2 °C. In cold climates it can only be kept as a young plant under glass.