The Summer Solstice is the fourth solar term of summer and the tenth of the whole year. Its arrival marks the beginning of midsummer, characterized by hot weather and frequent heavy rain. Plants flourish with lush leaves, and refreshing seasonal fruits like watermelons, bayberries, and lychees are starting to appear on the table.

Additionally, the Summer Solstice holds significant importance among the twenty-four solar terms. On this day, the sun shines directly on the Tropic of Cancer, resulting in the longest daylight hours of the year in the northern hemisphere. Due to its obvious astronomical significance, the Summer Solstice, along with the Winter Solstice, was among the first solar terms established by ancient observers. Building upon the foundation of the two, the ancient Chinese further divided the solar terms.

On the Summer Solstice, daylight reaches its peak. In conjunction with the ancient concept of yin and yang, it was believed that this day represented the peak of yang energy. Since extremes are thought to give rise to their opposites, this led to the idea that the peak of yang generates the birth of yin, encapsulated in the phrase "yang reaches its extreme and yin is born." The inclusion of this philosophical perspective added deeper meaning to the Summer Solstice.

The Summer Solstice is a crucial period for crop growth, and many folk activities during this time are aimed at praying for a good harvest. During the Zhou Dynasty, people offered sacrifices to deities on the Summer Solstice to ward off epidemics and disasters. In the Qing Dynasty, the royal family maintained the grand ceremony of sacrificing to the earth on this day, with the rites held at the Temple of Earth in Beijing during the Ming and Qing periods. These sacrificial rituals still exist today. For instance, in Jinhua, Zhejiang, people conduct ceremonies to honor deities of the land, praying for a bountiful harvest. In many regions, there is still a custom of eating noodles on the Summer Solstice. In the southwestern and southern coastal areas, eating lychees on the Summer Solstice remains a summer tradition.