Qingming,meaning clear and bright, is the day for mourning the dead. It falls in early April(usually 5th April -4th April in Leap Years) every year. It corresponds with the onset of warmer weather, the start of spring plowing, and of family outings.
In ancient China, Qingming was by no means the only time when sacrifices were made to ancestors. In fact such ceremonies were held very frequently, about every two weeks, in addition to other important holidays and festivals. The formalities of these ceremonies were in general very elaborate and expensive in terms of time and money.

In an effort to reduce this expense, Emperor Xuanzong of the Tang Dynasty declared in 732 AD that respects would be formally paid at the tombs of ancestors only on the day of Qingming.This is the custom that continues to date.