Baengno (Kor. 백로, Chin. 白露, lit. White Dew) is one of the twenty-four solar terms. It occurs between Cheoseo (Kor. 처서, Chin. 處暑, lit. End of Heat) and Chubun (Kor. 추분, Chin. 秋分, lit. Autumn Equinox), and falls approximately on September ninth on the Gregorian calendar. In the lunar calendar, Baengno generally falls in the eighth month, when the Ecliptic rises to 165° over the horizon.
The name “White Dew” derives from the fact that temperature at this time of year falls below the dew point, with dew forming on tree leaves and grass overnight. In the ancient Chinese calendar, the period between Baengno and the autumnal equinox was divided into three five-day periods. The first period was described as the time when wild geese returned home; the second when swallows began their southward journey; and the third when birds gathered food for winter.
Baengno occurs after the rainy season when the skies have cleared. Occasional typhoons and high tidal waves occur at this time and these events can damage crops. People in South Jeolla Province consider it a bad omen if the first frost is seen before Baengno. They also believe that for the year’s rice farming to be successful, grain must finish ripening before Baengno. The year’s first frost is usually followed by frigid winds and significant temperature drops; rice plants that start bearing grain late often do not mature fully, and this eventually translates into poorer crop yields. As the weather at Baengno can significantly affect the harvest, farming households carefully observe weather changes during this period. In particular, windy weather at Baengno is considered an indicator of potential crop damage.