Thai vegetable planting calendar: central Thailand month by month
What to plant each month in central Thailand across the hot, rainy and cool seasons, which crops don't suit the rains, and how to stagger sowings of greens.
- Central Thailand has three seasons: hot from about mid-Feb to mid-May, rainy from about mid-May to mid-Oct, cool from about mid-Oct to mid-Feb. Actual start dates shift every year.
- The cool season is the easiest time to grow vegetables: cooler weather helps growth and cuts pests and disease.
- Onion, shallot, garlic and carrot don't suit the rainy season; save them for after the rains.
- Leafy greens such as water spinach, Chinese kale and lettuce are ready in 20-35 days; sow a new round every 2-3 weeks for a steady supply.
Central Thailand has three seasons: hot from about mid-February to mid-May, rainy from about mid-May to mid-October, and cool from about mid-October to mid-February. Planting in step with the seasons is the most effective shortcut for growing without pesticides, because vegetables growing in the weather they like are stronger and get less pest and disease trouble.
This is lesson 15. It draws on season data from the Thai Meteorological Department and recommendations from the Department of Agricultural Extension, as a guide for home vegetables in central Thailand, not a fixed timetable.
Central Thailand’s three seasons
| Season | Approximate period | What it’s like |
|---|---|---|
| Hot | mid-Feb to mid-May | hottest in April; soil dries fast |
| Rainy | mid-May to mid-Oct | wettest in August and September |
| Cool | mid-Oct to mid-Feb | coolest in December and January |
Actual start dates change every year. In 2024, for example, the Thai Meteorological Department declared the rainy season started on 20 May; it only declares a season once wind, rain and temperature have shifted.
Why the cool season is easiest
A country report on Thai vegetables published with the World Vegetable Center explains that cooler temperatures spur plant growth and curb pests and diseases, giving higher yields than in the hot season, which is why farmers favour growing vegetables in the cool season after the rice harvest. If you’re planting for the first time, starting between late October and November gives you the best odds.
You can grow in the hot and rainy seasons too, with extra care: mulch and shade in the heat, as in vegetables in the hot season, and raised, well-drained beds in the rains, as in the rainy-season garden.
Month by month
| Month | Season | Sow or plant | Watch for |
|---|---|---|---|
| Jan | Cool | lettuce, short-cycle greens, onion, garlic, carrot | dry air; soil dries faster than you expect |
| Feb | Cool to hot | last lettuce sowing; start okra, pumpkin | have mulch ready before the real heat |
| Mar | Hot | okra, pumpkin, water spinach | mulch; shade cloth for leafy greens |
| Apr | Hottest | water spinach; focus on keeping existing beds going | water early in the morning |
| May | Hot to rainy | pak choi, water spinach, yard-long bean, ivy gourd | finish raising beds before the heavy rain |
| Jun - Jul | Rainy | short-cycle greens, cucumber, luffa, bitter gourd, wax gourd, pumpkin, yard-long bean | dry spells; keep watering |
| Aug - Sep | Wettest | short-cycle greens on raised beds | standing water, fungal disease, snails |
| Oct | Rainy to cool | start lettuce seedlings | don’t plant onion, garlic, carrot until the rain is over |
| Nov - Dec | Cool | lettuce, leafy greens, onion, garlic, carrot | prime time for home vegetables; plant plenty |
Where each column comes from:
- Rainy season: the Department of Agricultural Extension (DOAE) recommends pak choi, water spinach, lettuce, ivy gourd, garden pea, yard-long bean, cucumber, pumpkin, wax gourd, bitter gourd and luffa, and lists onion, shallot, garlic and carrot as unsuitable. This calendar moves that second group to the cool season, after the rains.
- Hot season: DOAE promotes low-water crops such as pumpkin, okra, watermelon, peanut and mung bean for the period after the rice harvest, roughly November to April. For a home garden, okra and pumpkin are the everyday picks.
- Lettuce: DOAE data in the World Vegetable Center report give planting from about October to February and harvest from about November to March.
- Water spinach: the same data list it as planted and harvested all year.
Seasons don’t start on a calendar date. Look at the actual rain and weather before you plant, and treat this table as a starting point.
Worked example: staggering leafy greens in the cool season
Leafy greens such as water spinach, Chinese kale, lettuce and spring onion are ready in 20-35 days. Sow a whole bed at once and you’ll have more than you can eat in one week, then nothing for a month. Try staggering instead:
- The cool season runs from about mid-October to mid-February: about 4 months, or roughly 120 days.
- If a crop takes 35 days, one spot can produce about 120 ÷ 35 ≈ 3 rounds. A faster 30-day crop gives about 4.
- Divide a 1 x 2 m bed into three sections of about 0.67 m² each.
- Sow the first section in early November, the second two weeks later, the third two weeks after that.
- The first section is ready around late November to early December. Resow it as soon as it’s cleared, and you’ll have greens to pick roughly every two weeks until the end of the cool season.
Days to harvest vary by variety, so go by the seed packet.
Adjusting for other regions
This calendar is for central Thailand. The north and northeast are cooler and grow a wider range of temperate vegetables. In the south the rain can continue to around mid-January, so from October to January gardens there still need rainy-season beds. If in doubt, your district or provincial agriculture office has local advice.
Common mistakes
- Planting onion, garlic or carrot in the middle of the rains. DOAE lists these as unsuitable for the rainy season.
- Going only by the month number. In a year when the rains come or go late, crops planted to the table meet the wrong weather.
- Sowing a whole bed of greens at once. A glut for one week, then nothing for a month.
- Planting new seedlings in the hottest weeks without enough water. April is the hottest month of the year; small seedlings with shallow roots dry out fast.
- Not adjusting for your region, such as using the central calendar unchanged in the south.
Sources
- Country Report Thailand: seasons and seasonal temperatures — Thai Meteorological Department / WMO
- Advice for caring for vegetables in the rainy season, from the Department of Agricultural Extension (Thai) — Daily News
- DOAE shares drought-tolerant crop know-how: five crops (Thai) — Thairath
- Thailand (Dynamics of Vegetable Production, Distribution and Consumption in Asia) — World Vegetable Center
FAQ
I live in the north or the south. Does this calendar work for me?
As a rough guide, but adjust it. The north and northeast are cooler. In the south the rain continues to around mid-January, so while central Thailand is drying out, southern gardens still need rainy-season beds. Your district or provincial agriculture office can advise for your area.
What can I grow all year round?
Water spinach (pak boong) is the clearest example: Department of Agricultural Extension data list it as planted and harvested all year. Other short-cycle leafy greens also grow across several seasons, given enough water and shade in the hot season and raised beds that don't flood in the rains.
The rains are late this year. Should I shift the calendar?
Go by the actual weather rather than the month. The Thai Meteorological Department declares each season only once wind, rain and temperature have changed. If it's still raining hard, hold off on crops that dislike rain; if the rain stops early, you can start cool-season crops sooner.
General information, not medical advice. If you are pregnant, take regular medication, or have a liver or kidney condition, ask a doctor or pharmacist before taking herbs beyond normal food amounts.