Plum entry is called "plum entry" and "mildew entry". Refers to the day when the rainy season begins. Meteorological Meiyu refers to a rainy period from early summer to midsummer, and then enters Meiyu period. Different places have different climates and seasons, and the flowering period of plum blossoms is also different. We can't rely on the plums on the calendar to guide our life and production, but we should listen to the plum rain forecast released by the Meteorological Observatory. Plum blossom is commonly known as "broken plum", which generally refers to the date when the plum rain ends. Meiyu in Jianghuai area of China usually ends on July 8-12, and the plum blossom period will be delayed in some years, for example, it does not end until1August 2, 954, and the plum blossom period lasts for 63 days. When the meiyu ended, more areas entered the hot summer.

The weather-determined plums are different from those in the calendar. In meteorology, the division of plum blossom period, plum blossom period and plum rain period is determined according to the background of large-scale weather circulation situation, the geographical distribution characteristics of weather system, the geographical distribution position of precipitation and the changes of meteorological elements.