San Fu is the hottest period in the year according to in Chinese Farmer's Calendar (Almanac). San means three in Chinese. Fu means to hide for the summer heat. The First Fu Day is the third Male Metal Day after Summer Solstice. The second Fu Day is the 4th Male Metal Day of Summer Solstice. The Third Fu Day is the first Male Metal Day after Start of Autumn. These three Metal Days are called San Fu (Three Fu) Days. Therefore, Chinese know the hottest day in the year is not Summer Solstice. After Summer Solstice, the heat keeps store on the ground. This is good for food crop in the farm to become healthy.
The Start of Autumn and Summer Solstice are the solar times of 24 Solar Segment Points in Chinese Farmer's Calendar, which combines solar, lunar and Stem-Branch calendars. More information is at Chinese Lunar Calendar page.
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