1, ward off evil spirits. There is a reason to hang wormwood and cattail (Pujian) at the entrance of Dragon Boat Festival. Usually mugwort leaves, banyan trees and calamus are tied into a bundle with red paper and then inserted or hung on the door. Because cattail (Acorus calamus) is the first of five auspicious days, symbolizing evil sword, because the growing season and shape are regarded as "the breath of a hundred yin", and the leaves are sword-shaped and can be inserted at the door to ward off evil spirits.
2. Pray. Wormwood represents a hundred blessings, and inserting it at the door represents a hundred blessings, which can make the owner healthy.
3. insect repellent. Artemisia argyi is also known as Artemisia argyi and Artemisia argyi. Its stems and leaves contain volatile aromatic oils. Its unique fragrance can repel mosquitoes, flies, insects and ants and purify the air.