Each of the full moon after the spring equinox the first Sunday of Easter.
During the holiday season, in accordance with the traditions and customs of the people cooked egg painted red, representing Swan Li Xue, also said that after the birth of the Goddess lives happily.This custom has a long history, the Easter egg is a symbol of new life because it portends the advent of that new life will be from the-from birth.
参考资料:http://baike.baidu.com/view/1462.htm