Cold Dew

Meaning

Cold Dew, Hanlu, is the seventeenth of the twenty-four solar terms: the Sun at 195°, about 8 October. The dew that was white a month ago is now cold, close to frost; in the north the first freezing nights are near, and in the south autumn at last feels like autumn.

It is an opening term: it opens the Dog month, the ninth solar month and the last of autumn, whose branch, Xu, is the storehouse of Fire and a branch of Earth. The harvest is being brought in and stored, and the season begins to close.

Its three pentads are the wild geese arriving as guests from the north, the sparrows going into the sea and turning into clams, as the old observers said of the birds that vanished while the shellfish thrived, and the chrysanthemums putting out their yellow flowers.

In practice

• In BaZi a birth from this instant belongs to the Dog month and its pillar; a birth within five minutes of it is marked uncertain, since a slightly different time would give the Rooster month.
• In Chinese astrology the month animal turns from the Rooster to the Dog, and the Cycles lens begins the Dog month’s reading here.
• In Feng Shui the month’s star changes, one less than the Rooster month’s.
• The Calendar marks it on its day, with the Sun at 15° Libra, as the opening of the Dog month.

Across traditions

• In Japan the chrysanthemum festival, Chōyō, on the ninth day of the ninth month, falls near Kanro in the old calendar; in Korea the term is hallo, in Vietnam hàn lộ.
• In Western astrology the Sun is at 15° Libra, the middle of the first autumn sign, a fortnight after the equinox.
• In Europe the same weeks are those of the last grape harvests and the first frosts in the mountains, the turning point when gardens are put to bed.

Origin and history

The Monthly Ordinances of the Book of Rites name the signs of this month, the guest geese, the sparrows and the clams, and the chrysanthemums with their yellow flowers; the Huainanzi, in 139 BC, sets the term among the twenty-four. The Double Ninth Festival, on the ninth day of the ninth lunar month, usually falls in or near its fortnight: families climb hills, drink chrysanthemum wine and visit the old.

The chrysanthemum is the flower of this season in Chinese poetry. Tao Yuanming, in his “Drinking Wine” poems of the 5th century, picks chrysanthemums by the eastern hedge and sees the southern hills in the distance, a scene of quiet that generations of painters and poets returned to. Crabs and new rice wine are the tastes of these weeks along the Yangtze, where a saying gives the ninth lunar month to the female crabs and the tenth to the males.

How Ulune calculates it

Ulune takes Cold Dew as the instant the Sun’s apparent longitude reaches 195°, from its table of the solar terms computed with the Swiss Ephemeris for 1800 to 2200. The Dog month and its pillar begin at that instant, whatever the clock or the time zone. In 2026 it fell on 8 October at 06:29 UT.

Correspondences