1. Rape flowers begin to bloom in March and April every year, and the flowering time will be different in different years.

2. Generally, flowering begins three months after planting, and the flowering period is about 30 days. Affected by the region, the rape blossoms in southern Shaanxi, northern Sichuan and Jianghuai areas were in full bloom at the end of March and early April, and lasted until early May. The farther north, the later the flowering time of rape, and Qinghai Province in the north will not bloom until July.