GrowSabzHow to grow longan in pots
Also called Dragon's Eye, lam yai, lengkeng, longyen · Dimocarpus longan
لونگان
- ☀️ Sunlight
- 6–8hours daily
- 💧 Water
- 11.3 Levery 3 days, 50 L pot
- 🌡️ Ideal temp
- 20–30°C
- 🪴 Min pot
- 50 L45 cm deep
- 🧺 Harvest
- 120–180days from sowing
- ⚖️ Yield
- 1.5 kgper 20 L pot
Longan is a long game. It takes years to reach cropping size from seed, which is why most growers start from a nursery plant. Container growing is entirely possible, but the container has to be sized for a plant that will live in it for years.
Short answer
Grow longan in a 50 litre container at least 45 cm deep, watering about 1500 ml per 10 litres of soil every 3 days, and keep temperatures between 20 and 30 °C. First harvest comes 120–180 days after sowing.
Where to plant it
What size pot does longan need?
50 litres and 45 cm deep is the realistic minimum for a single plant. Pick a container below to see what changes.
| Container | Minimum size | Depth | Notes |
|---|---|---|---|
| Pot | 50 L | 45 cm | Requires large pot with excellent drainage, eventually needs to be planted in ground |
| Grow bag | 50 L | 45 cm | Fabric bags promote air pruning, but dry out faster |
| Open ground | — | 100 cm | Requires ample space and deep, well-draining soil |
| Raised bed | 100 L | 60 cm | Ensure sufficient depth for root system development |
Watering
How often should you water longan?
Every 3 days through the growing season, at about 1500 ml per 10 litres of soil — daily in hot weather, every 7 days when it turns cool. Water in the early morning. Deep root watering works best.
Too little water
- wilting leaves
- leaf scorch
- fruit drop
- stunted growth
Too much water
- yellowing leaves
- leaf drop
- root rot
- stunted growth
Avoid: shallow frequent watering; standing water around trunk.
Climate
Can you grow longan where you live?
No hardiness zone needed — compare your actual temperatures against the plant's own limits.
| Ideal range | 20 – 30 °C |
|---|---|
| Survives | 0 – 40 °C |
| Germinates above | 20 °C — best at 25 °C, about 14 days |
| Flowers drop | above 35 °C, or below 10 °C |
| Sunlight | 6–12 hrs/day, best 8 |
| Frost | Medium High sensitivity |
The flower-drop thresholds matter more than the survival ones. A plant can be perfectly alive at 40 °C and still give you nothing.
How cold is too cold for longan? Check your temperaturesEnter your night low and day high — see if it survives, and if it will cropTimeline
Longan growing stages, day by day
Click any stage to see what's happening. Durations shift with temperature — a warm season runs roughly a quarter faster than a cool one.
Feeding
Fertiliser schedule for longan
Feed on the interval below, changing what you give as the plant shifts from making leaves to making fruit.
| Stage | What to use | Per 10 L | Every |
|---|
How to prepare each feed
Common mistakes
Why longan fails, and how to avoid it
- A container that is too small
Below 50 litres the root run is too shallow. The plant grows, flowers late, and drops whatever it sets because it cannot support the crop.
- Watering too lightly
A daily splash wets the top few centimetres and nothing else. Longan wants about 1500 ml per 10 litres of soil — one deep soak beats three shallow ones.
- Ignoring the flower-drop threshold
Above 35 °C, or below 10 °C, flowers fall before setting. The plant can look perfectly healthy and still give you nothing — shade it through the hottest hours.
- Harvesting too late
Left too long the colour changes, seeds harden and the flavour sharpens. Pick on the signs listed below, not on the calendar.
- Planting it beside Walnut
Releases juglone, a chemical toxic to many plants, which can inhibit the growth of longan trees.
Companions
What to plant with longan
Good neighbours
Nitrogen-fixing plants like peanuts or cowpeas enrich the soil, benefiting the longan tree's growth.
Roots produce a chemical that kills root-knot nematodes, protecting the longan's root system.
Acts as a dynamic accumulator, drawing nutrients from deep in the soil. Its leaves can be used as a nutrient-rich mulch.
Emits a strong scent that can deter various pests, including aphids and some types of fruit flies.
Keep apart from
Releases juglone, a chemical toxic to many plants, which can inhibit the growth of longan trees.
Other large, heavy-feeding trees or plants planted too close will compete intensely for water and nutrients, potentially stunting longan growth.
Problems
Longan pests and diseases
Each lists the weather that brings it on, so you know when to start checking rather than reacting once it's established.
Longan Psyllid humidity >70% · temp 25-30
Causes characteristic galls (blisters) on new leaves, leading to distorted growth and reduced photosynthesis. A major pest of longan.
Anthracnose humidity >85% · temp 20-30
Appears as dark, sunken spots on leaves, flowers, and fruits. Can cause flower blight, fruit rot, and premature fruit drop, especially in wet conditions.
Mealybugs humidity any · temp 20-35
Small, soft-bodied insects covered in white, cottony wax. They cluster on new growth, stems, and fruit, sucking sap and excreting sticky honeydew, leading to sooty mold.
Scale Insects humidity any · temp 20-35
Appear as small, immobile bumps on stems, leaves, and fruit. They suck sap, weakening the plant and causing yellowing leaves and reduced vigor. Also excrete honeydew.
Fruit Flies humidity >60% · temp 25-35
Lay eggs in ripening fruit, leading to larvae tunneling inside, causing internal rot and making fruit unmarketable. Can devastate a harvest.
Powdery Mildew humidity 50-70% · temp 20-27
White, powdery fungal spots appear mainly on the upper surface of leaves. Causes leaves to yellow, curl, and die off prematurely, reducing vigor.
Root Rot humidity any · temp any
Caused by overwatering and poor drainage. Symptoms include yellowing leaves, wilting, stunted growth, and soft, mushy roots. Can be fatal.
Algal Spot humidity >80% · temp 25-30
Appears as greenish-orange, velvety spots on leaves and stems. While usually not fatal, severe infections can reduce photosynthesis and vigor.
Sooty Mold humidity any · temp any
A black, powdery coating on leaves and stems, which grows on the honeydew excreted by sap-sucking insects (e.g., mealybugs, scale). Blocks sunlight, reducing photosynthesis.
Harvest
When to harvest longan
First picking falls between day 120 and day 180, and the plant then keeps producing for about 45 days. Pick often — what you leave on the plant signals it to stop making more.
How to tell it's ready
- Skin color changes from green to yellowish-brown or reddish-brown
- Skin is smooth and firm
- Fruit is easy to pull from the stem
- Taste is sweet and aromatic
How much to expect
Storing it: Store at room temperature for a few days, or refrigerate in a perforated bag for 1-2 weeks. Do not wash until ready to eat.
Questions
Longan: common questions
How long does longan take to grow?
About 1095 days from sowing to the first harvest, with picking usually starting between day 120 and day 180. It then keeps producing for roughly 45 more days. Warm weather pulls that forward; cool weather pushes it back.
What size pot does longan need?
At least 50 litres and 45 cm deep for one plant. A raised bed wants 100 litres of soil and 60 cm of depth.
How often should I water longan?
About 1500 ml per 10 litres of soil, every 3 days in normal weather — daily when it is hot and every 7 days when cool. Water in the early morning.
What temperature does longan need?
It does best between 20 °C and 30 °C and survives from 0 °C to 40 °C. Seed needs soil above 20 °C to germinate, ideally around 25 °C.
Can I grow longan in winter?
It tolerates cold better than most, down to about 0 °C, so a sheltered spot or a cold frame will often carry it through.
How do I know when longan is ready to harvest?
Skin color changes from green to yellowish-brown or reddish-brown; Skin is smooth and firm; Fruit is easy to pull from the stem; Taste is sweet and aromatic. Once picked: store at room temperature for a few days, or refrigerate in a perforated bag for 1-2 weeks. do not wash until ready to eat.
How much does one longan plant produce?
Roughly 1.5 kg from a 20 litre container, or about 100 kg in open ground. Larger containers give proportionally more, up to a point.