Watering and Turning: Controlling Pile Temperature and Moisture
A wodui pile looks like nothing more than a small mountain of tea leaves, but it's really more than a month of continuous temperature and moisture management. Every day the master measures the pile temperature, feels the leaves, and smells the air to decide when to add water and when to turn.
How Much Water Is Added?
Sun-dried maocha holds only about 10% moisture, too dry for microbes to get going, so the first step of wodui is adding water:
- Typical ratio: industry experience is to add water at about 30–40% of the maocha's weight, adjusted for how dry the maocha is, the air temperature, and how tender the leaf is.
- Target moisture: a 2026 study following industrial fermentation at Xiaguan started with maocha at 8.3% moisture and added mountain spring water to bring it to about 40%.
- Evenness: water is sprinkled while the leaves are tossed so every leaf absorbs some, with no dry layers or waterlogged corners.
Too little water and the pile won't heat up, so fermentation is slow. Too much and the leaves rot, form lots of clumps, and tend to turn sour.
What Temperature Is the Pile?
After watering, the tea is heaped up, commonly about 1 meter high, sometimes covered with damp cloth to hold in heat and moisture. After a day or two the microbes become active and the pile temperature gradually rises.
- Suitable range: generally 50–65°C. In one wodui process measured in research, the pile stayed mostly at 51–63°C from day 3 to day 26, falling back to about 45°C toward the end.
- Upper limit: Yunnan's technical processing guidelines recommend keeping the pile below 65°C. If it gets too hot, the tea "burns": it darkens, the aroma turns scorched and stuffy, and the spent leaf chars.
Masters push thermometers into the pile at different depths and also reach in by hand to feel the temperature and moisture.
Why Turn the Pile?
Turning means breaking the whole pile apart, tossing it, and heaping it up again. It serves several purposes:
- Releasing heat: when the pile gets too hot, opening it up lets the heat escape.
- Adding oxygen: it lets air into the pile for the aerobic microbes.
- Evening things out: the core, surface, and bottom of a pile differ in temperature and moisture, and turning brings the whole pile to the same level of fermentation.
- Breaking up clumps: tea that sticks together in the heat and damp has to be broken apart, or the inside won't ferment evenly. The clumps that won't break up end up as laochatou.
- Adding water: if the leaves seem dry during turning, a little more water may be added.
How Many Times Is It Turned?
| Item | Common range |
|---|---|
| First turning | About 1–2 days after piling, once the temperature has risen |
| Interval between turnings | About every 7–10 days |
| Number of turnings | 5–8 |
| Total days | About 30–45 days, with some methods running longer |
The industrial fermentation in the study above was turned every 7–10 days, 8 times in all. Parameters vary widely by factory, season, and material, and the real judgment comes from experience.
Does Water Quality Affect Wodui?
Yes. The water used goes straight into the leaves, and its minerals, impurities, and microbes can all affect fermentation:
- Clean: the water source must be clean and free of odors.
- Consistent: a factory tries to use the same water every time so each pile starts under the same conditions.
- Hardness: the tea world generally believes softer water with moderate minerals is better, and very hard water may darken the liquor.
Many long-established factories emphasize their water sources; in the study, Xiaguan used mountain spring water. How much water quality matters, though, hasn't been systematically compared yet. The safe statement is that clean, consistent, odor-free water is the baseline.
Looking, Smelling, Touching
Between turnings, the master tracks the fermentation by the senses:
- Looking: the leaves shift from yellow-green to yellow-brown, then reddish brown, and finally chestnut red-brown.
- Smelling: early on there's sourness and greenness, in the middle a ripe sweetness appears, and later it turns to a ripe, aged aroma.
- Touching: grabbing a handful, squeezing, and releasing it shows the moisture level. A pile that's too sticky or wet needs attention.
When color and aroma are where they should be, the master prepares to "open trenches" so the pile can slowly dry, moving on to the steps in After the Pile. How to judge fermentation level is covered in Fermentation Levels in Ripe Pu'er.
Turning Is Hard Work
Turning sounds simple, but it's heavy physical labor. A pile of over ten tons has to be raked and shoveled open layer by layer, broken up, and heaped back up by workers with wooden rakes and shovels, in a fermentation room that's hot, humid, and thick with the smell of ripe tea. One turning often takes several people the better part of a day. Some factories have recently brought in turning machines to reduce the labor, but many details, such as which section needs extra turning or where to add water, still depend on the master's eyes and hands.
FAQ
How much water is added for wodui? Industry experience is about 30–40% of the maocha's weight, bringing moisture to around 40%, adjusted for the material and the weather.
What temperature is a wodui pile? Generally 50–65°C; Yunnan's guidelines recommend no more than 65°C.
Why turn the pile? To release heat, add oxygen, even out fermentation inside and out, and break up clumps.
How many times is it turned? Commonly every 7–10 days, 5–8 times in all, over about 30–45 days.