Every year, it begins on the first day of the first lunar month and ends on the last day, lasting for one month. That is, it starts from summer to the third Geng Day in the future and ends the day before the second Geng Day after beginning of autumn.

Double Ninth Festival is a traditional food festival in China. "Eating and supporting Yang in dog days" has a long history in Xuzhou, Jiangsu Province, which can be traced back to the Yao and Shun period at the earliest. Since ancient times, Xuzhou folks have said that "a bowl of soup for a sheep does not require a doctor to prescribe a prescription".

"Fuyang", that is, mutton after crouching. "Biography of Yang Hanyun" records: "Tian family is hard, old and full of wax, sheep full of lambs, fighting for wine." Eating mutton in dog days is a great pioneering work, which can clear away heat, sweat and detoxify, and drive away the toxic moisture in winter and spring.