Generally speaking, high mountains refer to mountains with a relatively high altitude within a certain regional range. The growth of tea trees is profoundly influenced by altitude in terms of climate, rainfall, temperature, humidity, soil, sunlight, ground temperature, growth cycle, and other aspects, which deeply affect the quality of tea leaves.

◎1. As altitude increases, atmospheric pressure decreases, the air becomes thinner, and the transpiration of tea trees accelerates accordingly. The buds and leaves themselves have to secrete a resistin to inhibit excessive water transpiration. This resistin is the precious component of tea—aromatic oils. Therefore, high mountain tea has a relatively high aroma, leaves a lasting fragrance at the bottom of the cup after brewing, and the fragrance persists for a longer time.

◎2. In high-altitude areas, strong ultraviolet radiation easily ionizes nitrogen in the air, which then infiltrates the soil. Abundant nitrogen sources create conditions for tea trees to accumulate aromatic substances.

◎3. Mountainous areas mostly have sandy soil, with deep soil layers, good permeability, and suitable acidity. Dense forests in the mountains result in more fallen leaves, making the soil fertile and rich in organic matter, which is very suitable for the growth of tea trees.

◎4. In high mountain areas, where few people set foot, the air quality is good, with almost no pollution. Large trees, relying on their own resistance, experience little interference from pests and diseases.

◎5. In high-altitude mountainous areas, clouds and mist弥漫, and the quality of solar radiation and light received by tea trees is different from that in flatlands. Long-wave light is blocked by clouds and mist and reflected, while short-wave light has strong penetrating power and acts on tea trees to synthesize more alkaloids and phenolic substances. This is also one of the reasons why high mountain tea is rich in internal substances.

◎6. High mountain areas have large temperature differences between day and night. During the day, the temperature is high, sunlight is sufficient, and the photosynthetic capacity of tea trees is strong, synthesizing more substances. At night, the temperature is low, the respiratory stomata on the back of leaves close, and the respiration of tea trees slows down accordingly. With less respiratory consumption, the nutrients of tea trees can be accumulated and stored more. This is also one of the reasons why tea from high mountain areas is rich in internal substances. In addition, the large temperature difference between day and night is also conducive to the nitrogen and phosphorus metabolism of tea trees, speeding up the internal circulation and promoting the growth of tea trees.

◎7. In cloud-shrouded mountainous areas, water vapor has a strong ability to reflect ultraviolet rays, and more red and orange light penetration synthesizes rich amino acids and carbohydrates. Ancient tea trees in Yunnan generally grow in high mountain forests. The tall trees of the tropical rainforest block the strong sunlight for these ancient tea trees, making the internal substances of these ancient teas more harmonious and the taste softer.

◎Overall, influenced by the regional environment, high mountain tea is characterized by rich internal substances, harmonious proportional relationships, high and lasting aroma, and being aesthetically pleasing and resistant to brewing.