Longan

Tree facts

Scientific name

Dimocarpus longan

Origin

Southern China to Myanmar

Tree size

30–40 ft if left alone; can be kept at 12–15 ft with pruning after harvest

Growth rate

Medium

Sun

Full sun

Soil

Well-drained sand or loam. Tolerates Florida's sandy and limestone soils better than lychee.

Soil pH

5.5–7.5

Pollination

Self-fertile; one tree is enough

Cold hardiness

Young trees are damaged near 32°F; mature trees take brief dips to about 26–28°F

USDA zones

10–11 (9b with protection)

Years to first fruit

3–5 for an air-layered or grafted tree

Season

Jul–Sep

Water

About every 7 days once established, without rain; more in heat, in pots and while young

Feeding

About every 90 days, Mar–Aug

Pruning

Sep–Oct

Taste

Sweet, musky and less acidic than lychee, with a hint of spice

Nutrition

High in vitamin C, with some potassium and copper

Is longan safe to eat? Edible and toxic parts

What you can eat

• Ripe flesh, raw or cooked
• Dried flesh, used in teas, soups and desserts

Toxic parts and cautions

• Good to know: The seed isn't eaten. Its round shape makes whole fruit a choking hazard for small children.
• Good to know: Eat only ripe fruit. Longan is a close relative of lychee, whose unripe fruit can lower blood sugar.

Pets: A little peeled, seeded ripe flesh is fine for dogs. Keep seeds and skins away from pets.

How to eat and enjoy longan

• Fresh, peeled from the cluster
• Dried longan in Chinese tea, congee and sweet soups
• Canned in syrup, or in Thai desserts with coconut milk
• Added to fruit salads and smoothies

Longan varieties (6)

• Biew Kiew · also Bieu Kieu

  A late Thai longan with firm, sweet flesh and a small seed.

  Origin: Thailand · Taste: Sweet, firm · Season: Sep–Oct

  Needs a cooler winter to flower and bears irregularly in South Florida.

• Diamond River

  A heavy-bearing longan with small to medium fruit and sweet flesh, commonly sold in Florida nurseries.

  Taste: Sweet · Size: Small to medium

• Edau · also Daw, E-Daw, Edaw

  Thailand's main commercial longan, with large fruit and sweet, crisp flesh.

  Origin: Thailand · Taste: Sweet, crisp · Size: Large

• Haew · also Haeo

  A late, large-fruited Thai longan with firm, sweet flesh.

  Origin: Thailand · Taste: Sweet, firm · Size: Large

• Kohala

  The standard longan in Florida and Hawaii, with large fruit and sweet, aromatic, slightly spicy flesh.

  Origin: Hawaii · Taste: Sweet, spicy, aromatic · Season: Aug–Sep · Size: Large

  Flowers with less winter cold than most Thai cultivars.

• Sri Chompoo · also Si Chompoo, Sri Chompu

  A Thai longan with pinkish-tinged flesh and a rich, sweet flavor.

  Origin: Thailand · Taste: Rich, very sweet

Pests and diseases to watch for

• Lychee erinose mite

  Felt-like brown or reddish blisters under leaves; leaves curl and new growth is stunted.

  What to do: Cut off and bag infested shoots.

• Scale insects

  Small bumps, waxy or shell-like, on stems and leaf veins; sticky honeydew and black sooty mold below.

  What to do: Scrub small colonies off with a soft brush.

• Mealybugs

  White cottony clusters in leaf joints, under leaves and on fruit stems; honeydew and sooty mold.

  What to do: Blast off with a strong spray of water.

• Aphids

  Clusters of tiny soft insects on new shoots; leaves curl and get sticky.

  What to do: Spray off with water.

• Sooty mold

  Black, papery film on leaves and fruit that wipes off; it grows on honeydew.

  What to do: Control the insects making honeydew; the mold then weathers away.

• Spider mites

  Fine pale speckling on leaves, dusty undersides and fine webbing; leaves bronze and drop.

  What to do: Hose the undersides of leaves.