What are the suitable growing conditions for tea plants? A detailed explanation of the suitable growing environment

Heat: The heat condition is generally expressed by temperature, and what mainly affects the growth and development of tea plants is air temperature and soil temperature. The biological minimum temperature for tea plants is generally around 10°C (the growth starting temperature); early-budding varieties may have a minimum below 10°C, while late-budding varieties have one above 10°C. The optimum temperature for tea plant growth refers to the temperature at which tea plants grow most vigorously and actively; it varies with variety and place of origin, and is mostly 20°C-30°C. Temperature difference: the day-night temperature difference directly affects the accumulation of photosynthetic substances. When daytime temperatures are high, more photosynthetic substances are synthesized, and when nighttime temperatures are low, less respiratory product is consumed; therefore, a large day-night temperature difference is favorable for the formation of biological yield. From the perspective of different seasons, the effect of spring temperature on new shoot growth is clearly greater than that in summer and autumn. For the more suitable annual accumulated temperature for tea plant growth, the active accumulated temperature not lower than 10°C should be around 5000°C. After entering December, when the average temperature is lower than 10°C, tea plants enter overwintering dormancy; when the temperature drops to 1°C-2°C, sprouted tea buds will scorch and wither, and when it drops to -2°C, most tea flowers drop off and die. Generally, shrub-type tea plants have strong low-temperature tolerance (around -12°C), small tree-type tea plants are next (around -8°C), and tree-type tea plants are the weakest (Yunnan large-leaf variety is about -5°C); the minimum critical temperature that tea plants can tolerate varies with variety, tree age, tree vigor and the weather conditions when low temperature occurs. The maximum critical temperature that tea plants can tolerate is 45°C; under natural conditions, when the daily average temperature is greater than 30°C, tea shoots grow slowly; if 35°C persists for several days, new shoots will wither and leaves will fall. Varieties with southern-type genes often have a stronger high-temperature tolerance.

Soil temperature affects the growth and development of the tea plant root system; the optimum temperature for root growth is 25°C-30°C; when the soil temperature is 10°C, the effect on the root system is relatively small; and the ground temperature of each soil layer is highly significantly positively correlated with new shoot growth. A ground temperature of 14°C-20°C is most suitable for new shoot growth. The effect of ground temperature on new shoot and root growth is related to soil texture, moisture conditions and tea plant variety, etc.