Why did Tomb-Sweeping Day insert willow leaves or peach leaves?

Tomb-Sweeping Day wants to insert willow leaves or peach leaves to ward off evil spirits. In China, Tomb-Sweeping Day, July 30th and October 1st are the three major ghost festivals, which are the time for ghosts to haunt. In order to prevent the harassment and persecution of ghosts, people put willows and put them on. Willow has the function of ward off evil spirits in people's minds.

Influenced by Buddhism, people think that willows can exorcise ghosts and call them "ghost trees". Guanyin dipped willow branches in water to help all beings. Jia Sixie of the Northern Wei Dynasty said in the Book of Qi Yao Min: "Take a willow branch and put it on the house, and a hundred ghosts will not enter the house." Tomb-Sweeping Day is a ghost festival. When wicker sprouted, people naturally inserted willows to ward off evil spirits.

Tang people thought that wearing willow branches could get rid of the harm of poisonous insects. After the Song and Yuan Dynasties, the custom of inserting willows in Tomb-Sweeping Day was very popular. When people come back from an outing, they stay at home to avoid insects. Whether recorded in folklore or historical records, planting willows in Tomb-Sweeping Day is always related to avoiding diseases and epidemics. During the Spring Festival, the climate gets warmer, and all kinds of germs begin to multiply in large numbers. People can only hope to shake willows and branches in the case of poor medical conditions.