Like wine grapes, tea has an ideal growing climate in which photosynthesis occurs during the day to produce the best flavor.
During the day, photosynthiates are built up in the leaves from the conversion of carbon into high-molecular-weight compounds of flavor, aroma, and structure.
But maximum photosynthesis occurs at approximately 87 degrees Fahrenheit. (This is true of most deciduous plants, plus or minus a few degrees.) At over 98 degrees, photosynthesis stops. For glycolosis, which happens at night, the right temperature is also important.
In addition to providing the perfect growing conditions, the Fujian Mountains are also very clean. For purity of the soil, water and air, mountain farms are the best spots.