A longan or dragon eye tree is perfect if you like lychees and rambutans but your climate isn’t quite tropical enough, as they will tolerate much cooler temperatures. Longan trees are Dimocarpus longan, an attractive small to medium sized tree with lots of lovely reddish new growth through spring and summer and a heavy canopy of shiny, green leaves, although you may want to keep them smaller or thin the canopy to make harvesting the fruit easier.
Slow growing to only about 6-7 metres, they will fit in many smaller gardens too, and will grow from tropical to subtropical zones, or also in less humid climates like California, or South and Western Australia, if they have plenty of protection from hot, dry winds in summer, which will probably cause the fruit to drop. Their preferred climate is a warm, humid summer followed by a cooler, dry winter. Some evidence suggests that areas with a number of days with minimum temperatures under 12 degrees C (54F) will produce better longan crops.
If you’re in a cooler district, create a warm microclimate for them in winter as cold, windy and rainy weather can interfere with pollination. As longans grow naturally as understory trees in the elevated rainforests of southern Asia, you will also need to protect your tree from direct sun, especially in its early years by growing it under shadecloth or in the dappled shade of another tree’s canopy. If you grow it unprotected, the leaves will inevitably burn, even in cooler climates. Longan trees are slightly more tolerant of frost than lychee.
Soil doesn’t need to be particularly rich but should be slightly acidic (pH of 5.5-6) and also well-drained, as longan trees will not tolerate ‘wet feet’ at all. A light, sandy loam is ideal. Although you could start them off in a large pot, they will eventually need to be grown in the ground to produce any quantity of fruit.
Flowers are scented, creamy-yellow and held in panicles and although there are both male and female flowers, the tree is self-fertile. Longan fruit appears in drooping clusters, ripening in mid to late summer. Each fruit is small and round, with a dull-yellow, thin outer ‘shell’ covering a white, translucent membrane (which is the fruit) and shiny black seed inside. Cut off the entire cluster but make sure you don’t harvest under-ripe fruit as it will not ripen after picking.
Growing them in Australia is easy along most of the east coast, with the added bonus that they are not attacked by fruit fly. There are people growing longans successfully in Perth and Victoria by creating the right microclimate. They also grow well in northern New Zealand.
In the USA they can be grown throughout the Zones 8-10 and also thrive in many parts of southern California.
Longan trees can be grown from fresh seed but, as seeds are very short lived, they are usually reproduced by cuttings or aerial layering (marcottage). New trees can take several years to become fruit-bearing.
– Kohala from Hawaii which is a more vigorous grower, and heavy fruiting, with soft and juicy fruit ripening early in the season. The tree often benefits from removing up to half of the flowers and fruit so that it produces larger, better quality fruit.
– Biew Kiew from Thailand which produce firmer, crispier fruit later in the season.
– Haew has larger firm-fleshed fruit with a thicker skin. It tends to crop better in alternate years.
– Chompoo, slow growing, with crisp fruit with a pinkish tinge.
This video from Daley’s Fruit in northern NSW shows why pruning your longan tree is a good idea:
Where to buy:
Australia – Daleys Fruit Nursery (NSW)
USA – California – California Tropical Fruit Trees; Champa Nursery; Ong Nursery
– Florida – Lychees Online
New Zealand – Subtropica, Waipu, Northland