The 72 Seasons of Japan

We are all familiar with the four seasons of the year—spring, summer, autumn, and winter—based on the changes in weather, ecology, and the number of daylight hours. However, these four seasons are too broad in scope to accurately depict the nuances of our weather and of our natural surrounding. To mark the passing of time and understand the variations throughout the year, many ancient East Asian cultures created calendars based on the sun and the phases of the moon. The Hindu calendar has 6 seasons, the Chinese calendar consist of 24 seasons, and the Japanese calendar is divided even more finely into 72 seasons.  

Photo credit: tawatchai07/Freepik

The Japanese calendar has the same four seasons we are familiar with in the West. However, each season is divided into six parts creating 24 sekki, each about fifteen days long. These periods are originally derived from the traditional Chinese lunisolar calendar, a method of time keeping where a year is divided according to the phases of the moon as well as the earth’s orbit around the sun.

The 24 sekki are again split into three ko for a total of 72 ko, or micro-seasons, each lasting for around 5 days. These seasons reflect the delicate rhythms of Japan’s ecosystems, each one correlating with an actual happening in the natural world at that moment, such as bamboo shoots sprouting, and wheat ripening.

“Every few days is a new season, a new opportunity. Small enough to take with lightness. Big enough to matter,” writes Quartz.

“Dealing with such micro-seasons, and paying attention to them, can keep us alert to the world around us, and our passing through it. Empty time feels less of waste when seen from the perspective of nature’s motions,” it continues.

Mark Hovane explains the Japanese calendar in some detail:

At the core of each of the four seasons of spring, summer, autumn and winter are the equinoxes and solstices starting from shunbun (vernal equinox), geshi (summer solstice), shubun (autumnal equinox) and toji (winter solstice). The beginnings of each season are also observed in risshun (beginning of spring), rikka (beginning of summer), risshu (beginning of autumn) and ritto (beginning of winter). These markers account for 8 of the 24 seasonal points. The other remaining 16 points are highly influenced by the weather and agricultural elements, such as rain, snow and the progress of the agrarian crop cycle, and feature names including usui (rainwater), keichitsu (insects awaken), shosho (manageable heat) or hakuro (white dew).

Japanese micro-seasons were originally introduced to Japan from Korea during the mid-6th century. The names assigned to each micro-season were originally derived from climatic and natural changes in Northern China. As a result, there were slight variations when applied to the Japanese context. In 1685, Shibukawa Shunkai, a court astronomer, took it upon himself to revise the names, aligning them more accurately with the local climate and nature of his native Japan. This modified calendar remained in use until 1873 when the Meiji government, in its pursuit of modernization, abolished the traditional calendrical system and adopted the Western solar-based Gregorian calendar. Notably, specific groups in Japan, including farmers, fishermen, and aesthetes, continued to uphold the traditional calendar alongside the mandated Gregorian calendar.

The 72 Japanese seasons

Risshun (Beginning of spring)
February 4–8	East wind melts the ice
February 9–13	Bush warblers start singing in the mountains
February 14–18	Fish emerge from the ice
Usui (Rainwater)
February 19–23	Rain moistens the soil
February 24–28	Mist starts to linger
March 1–5	Grass sprouts, trees bud
Keichitsu (Insects awaken)
March 6–10	Hibernating insects surface
March 11–15	First peach blossoms
March 16–20	Caterpillars become butterflies
Shunbun (Spring equinox)
March 21–25	Sparrows start to nest
March 26–30	First cherry blossoms
March 31–April 4	Distant thunder
Seimei (Pure and clear)
April 5–9	Swallows return
April 10–14	Wild geese fly north
April 15–19	First rainbows
Kokuu (Grain rains)
April 20–24	First reeds sprout
April 25–29	Last frost, rice seedlings grow
April 30–May 4	Peonies bloom
Rikka (Beginning of summer)
May 5–9	Frogs start singing
May 10–14	Worms surface
May 15–20	Bamboo shoots sprout
Shoman (Lesser ripening)
May 21–25	Silkworms start feasting on mulberry leaves
May 26–30	Safflowers bloom
May 31–June 5	Wheat ripens and is harvested
Boshu (Grain beards and seeds)
June 6–10	Praying mantises hatch
June 11–15	Rotten grass becomes fireflies
June 16–20	Plums turn yellow
Geshi (Summer solstice)
June 21–26	Self-heal withers
June 27–July 1	Irises bloom
July 2–6	Crow-dipper sprouts
Shosho (Lesser heat)
July 7–11	Warm winds blow
July 12–16	First lotus blossoms
July 17–22	Hawks learn to fly
Taisho (Greater heat)
July 23–28	Paulownia trees produce seeds
July 29–August 2	Earth is damp, air is humid
August 3–7	Great rains sometimes fall
Risshu (Beginning of autumn)
August 8–12	Cool winds blow
August 13–17	Evening cicadas sing
August 18–22	Thick fog descends
Shosho (Manageable heat)
August 23–27	Cotton flowers bloom
August 28–September 1	Heat starts to die down
September 2–7	Rice ripens
Hakuro (White dew)
September 8–12	Dew glistens white on grass
September 13–17	Wagtails sing
September 18–22	Swallows leave
Shubun (Autumn equinox)
September 23–27	Thunder ceases
September 28–October 2	Insects hole up underground
October 3–7	Farmers drain fields
Kanro (Cold dew)
October 8–12	Wild geese return
October 13–17	Chrysanthemums bloom
October 18–22	Crickets chirp around the door
Soko (Frost falls)
October 23–27	First frost
October 28–November 1	Light rains sometimes fall
November 2–6	Maple leaves and ivy turn yellow
Ritto (Beginning of winter)
November 7–11	Camellias bloom
November 12–16	Land starts to freeze
November 17–21	Daffodils bloom
Shosetsu (Lesser snow)
November 22–26	Rainbows hide
November 27–December 1	North wind blows the leaves from the trees
December 2–6	Tachibana citrus tree leaves start to turn yellow
Taisetsu (Greater snow)
December 7–11	Cold sets in, winter begins
December 12–16	Bears start hibernating in their dens
December 17–21	Salmon gather and swim upstream
Toji (Winter solstice)
December 22–26	Self-heal sprouts
December 27–31	Deer shed antlers
January 1–4	Wheat sprouts under snow
Shokan (Lesser cold)
January 5–9	Parsley flourishes
January 10–14	Springs thaw
January 15–19	Pheasants start to call
Daikan (Greater cold)
January 20–24	Butterburs bud
January 25–29	Ice thickens on streams
January 30–February 3	Hens start laying eggs