The sweet green rice ball is a Qingming Festival (Tomb Sweeping Day) food popular in Jiangsu and Zhejiang Provinces. It is also a must-have offering at ancestral rituals in the south of the Yangtze River. The custom of making sweet green rice balls dates back to the Zhou Dynasty over 2,000 years ago. One or two days before the Qingming Festival were designated as "cold food days", during which hot cooking is banned.

Another traditional food during the "cold food days" is "refined green rice", which is a variation of the sweet green rice ball. It is made of a mixture of glutinous rice powder and green mugworts (bromegrass juice in some cases) and stuffed with sweetened bean paste. This snack has been around for over 100 years. It is used as an offering in ancestral rituals, but more of a fresh festive food. Sweet green rice balls are jade-green in color, glutinous in taste and sweet in aroma. What's best about the snack is its sweet-but-not-cloying and fatty-but-not- greasy taste.