Start of Autumn (Liqiu) is the thirteenth solar term in the twenty-four solar terms, and it marks the beginning of autumn. It usually falls on August 7th or 8th in the Gregorian calendar. "Li" means the start, and "Qiu" refers to the ripening of crops. The changes in nature occur gradually, and during the period of Start of Autumn, the Yang energy gradually declines while the Yin energy increases, marking the transition from the dominance of Yang to the dominance of Yin. In the natural world, everything begins to grow and mature.

Start of Autumn signifies a shift in precipitation and humidity, indicating a decrease. However, it does not represent the end of hot weather as there is still a solar term called "End of Heat" after the Start of Autumn. During this period, the weather is still hot. It is said that the heat peaks during Sanfu, which includes the solar terms of Start of Autumn, End of Heat, Major Heat and Minor Heat. From a climatic perspective, the sun is scorching during the early autumn, and many regions are still experiencing heat. Start of Autumn is the third hottest solar term after Major Heat and Minor Heat among the twenty-four solar terms.

During the beginning of autumn, there is a folk custom of worshipping the Land God and celebrating a bountiful harvest. In ancient times, people would choose an auspicious day after the Start of Autumn to give thanks to the heavens and ancestors for their blessings, as well as to taste the newly harvested grains and rice to celebrate the hard-earned harvest.

In the southern regions, there is a custom called "biting autumn melon" on the day of the Start of Autumn, where people eat watermelon to prevent dryness in the autumn, which has become a tradition over time.

"Sun drying autumn" is a typical folk phenomenon with strong regional characteristics. In regions such as Hunan, Guangxi, Anhui, and Jiangxi province, where villages are located in mountainous areas with few flat lands, villagers have to use their front and back yards, as well as their window sills and rooftops, to sun-dry and hang their crops. Over time, this has evolved into a traditional folk custom.