Native to China, the longan -- Dimocarpus longan -- has been grown in the United States since the early 1900s, primarily in Florida, Hawaii and California. This fruiting tree can grow up to 40 feet tall and requires dry climates with winter rains and no frost. The longan's relatives include lychee and rambutan. Longan can be grown from seed if you cannot find a longan tree to purchase. However, the trees don't come true from seed -- meaning your seed-grown tree may not bear quality or familiar-tasting fruit -- so this is a less-reliable method.
Remove a 3-foot-diameter ring of sod in an area with full sun, well-draining soil and enough room for the longan tree to grow to maturity. Stick your trowel under the grass, work it around in a circle, then grasp the sod and pull it up.
Dig a hole three times as deep as the container holding your longan tree, and three to four times as wide, using your shovel.
Push some of the excavated soil back in the hole to make a cushion. Remove the longan tree from its nursery container and inspect its roots. Unwind any tangled roots before placing the tree in the hole at the same depth as it was planted in the container.
Mix equal amounts of compost and soil. Push the compost-soil mix into the hole to cover the tree's roots.
Water the longan tree until the soil compresses around the trunk and becomes saturated. Each time the soil around the tree dries out, water it thoroughly.
Place a 2-inch layer of mulch around the longan tree to cut down on weeds.
Fertilise the longan tree one month after planting with 0.113kg. of 6-6-6 fertiliser, applied according to the label directions. Fertilise your tree every six to eight weeks during the first year, gradually working up from 1/4 to 1/2 lb. per application.
Increase the amount of fertiliser each year. Apply 1/2 to 3/4 lb. of fertiliser every eight weeks during the second year; provide 3/4 to 1lb. of fertiliser every eight weeks during the third year. Continue increasing the fertiliser amount incrementally until you're feeding the longan tree 3 to 3 1/2lbs. of fertiliser two to four times a year by the seventh year.
Prune your tree once a year using hand pruners. Trim back the tips of branches by 1 to 2 inches to promote lateral branching. Remove branches that grow too close to the boot, since they will interfere with other shoots. The University of Florida recommends pruning longan trees to keep them at a height of 10 to 15 feet for easy fruit harvest.