The longan is an exotic round to oval Asian fruit with a tan rind, one shiny seed and musky white flesh. Longan trees will grow in U.S. Department of Agriculture plant hardiness zones 8 to 10, and they prefer cool, dry winters. Too much rainfall during that season encourages foliage growth rather than flowering. With its corky bark and glossy green leaves, the longan is attractive even when not producing.
Plant your longan tree in well-drained, slightly acid soil in full sun, at least 25 feet away from other trees or buildings. Plant it on a small hill or mound if your winters are wet.
Make your hole three times the depth and diameter of the young tree's root ball. Shovel some of the loose soil back into the hole and position the tree so that it grows at the same height -- or slightly higher -- than it did in the pot.
Cut the tree back to 4 feet if it is taller than that. Water it deeply and apply a couple inches of mulch. Give it 1/2 cup of organic fertilizer every few months in spring and summer, and continue to water the tree frequently while it is small.
Choose three or four of the strongest shoots the following spring and prune off the others. Cut those shoots back by a few inches and use weights or wedges to force them into a more horizontal position if necessary. Prune off all but two shoots on each branch in the third spring.
Cut back on water during the fall and winter after the tree reaches fruit-bearing age -- about four years for trees propagated from cuttings and six years for trees grown from seed. Give the tree five pounds of organic fertilizer just before it blooms in early spring, again in late spring, and once more just before harvesting the fruits in late summer. Refrain from fertilizing your longan during the fall or winter.
Watch for panicles of small greenish-yellow blossoms in early spring. Thin the fruits that form on those clusters when they are about the size of peas, by cutting off half of each panicle.
Wait for the fruits to change from chartreuse to tan before you harvest them. Taste one first to make sure it is ready before picking the others, because they won't continue to ripen after they are removed from the tree.
Snip off each cluster with pruning shears. Refrigerate the fruits in plastic bags until you are ready to use them.
Things You Will Need
- Pruning shears
- Organic fertilizer
- Some growers force longan trees to bloom with a potassium chlorate solution applied to the soil, sprayed on the leaves or injected into the trunk. This will reportedly cause the trees to blossom within 40 days.
- Don't count on longan trees to bear fruit every year.
- University of Florida IFAS Extension: Longan Growing in the Florida Home LandscapeFlorida Home Landscape;" Jonathan H. Crane, Carlos F. Balerdi, Steven A. Sargent, and Ian Maguire
- Tropical and Subtropical Fruits: Postharvest Physiology, Processing and Packaging; Jasim Ahmed, et al
- Tropical Fruits, 2nd Edition; Robert E. Paull, Odilo Duarte
- University of CA Cooperative Extension: Longan
- FAO Corporate Document Repository: Longan Production in Asia