Bailu, or White Dew, is the fifteenth solar term among the 24 solar terms and an important marker of the increasing chill in nature.

Meteorological conditions

Although the weather gradually cools, daytime temperatures can reach around thirty degrees Celsius. However, once the sun sets, temperatures quickly drop, sometimes falling to the twenties at night. The moisture in the air condenses into tiny droplets that cling to the stems and leaves of plants, creating a sparkling white appearance when illuminated by morning sunlight, which gives "Bailu (White Dew)" its beautiful name. Starting with Bailu, the "autumn melody" begins to resonate across the country, with temperature differences between day and night reaching 8°C to 16°C, making it one of the solar terms with the largest temperature variation in the year.

Cultural significance

Tasting Rice Wine: In ancient times in the Suzhou and Zhejiang regions, people had the custom of brewing rice wine during Bailu. This wine is made from glutinous rice, sorghum, and other grains, with a hint of sweetness and a fragrant rice aroma, known as "Bailu Rice Wine", often served to guests.

Worshiping Yu the Great: Yu the Great, the legendary hero who controlled floods, is revered by fishermen around Taihu Lake as the "God of Waterways". Every year, rituals honoring Yu the Great are held on the eighth day of the first lunar month, during Qingming Festival, the seventh day of the seventh lunar month, and at Bailu. Among these, the ceremonies during Qingming Festival and Bailu are the largest, lasting for a week.

Health tips

During this solar term, the temperature difference between day and night becomes quite pronounced, marking the official onset of cooler weather. Especially at night, with autumn winds blowing, it’s necessary to wear additional layers to keep warm and avoid catching a chill. Additionally, Bailu brings dryness that can deplete bodily fluids, leading to symptoms like dry throat and cracked skin. It's important to adhere to the principle of "nourishing qi and moisturizing dryness" by eating more vitamin-rich fruits and vegetables, such as pears, white fungus, honey, and radishes.