Most calendars give you four seasons. The traditional Japanese one gives you seventy-two, each about five days long and each with a name that reads like a line of poetry: the east wind melts the ice, swallows arrive, rotten grass becomes fireflies, wheat sprouts under the snow.
That habit of noticing small seasonal changes runs through Japanese poetry, food, gardens and design. This article explains where the 24 seasonal divisions and the 72 microseasons come from, how season words work in haiku, and a few practical ways to borrow the idea for your own desk.
The 24 sekki: seasons pinned to the sun
The nijūshi sekki, or 24 solar terms, divide the year according to the sun’s position. Each term marks a further 15 degrees of the sun’s apparent path through the sky, so they fall at roughly the same date every year, give or take a day. Japan’s National Astronomical Observatory still defines them this way: the spring equinox (shunbun) is the moment the sun reaches 0 degrees, the autumn equinox (shūbun) the moment it reaches 180.
The system came from China, where the names were based on the climate of the North China Plain, and it spread to Japan along with the lunisolar calendar. Its most important job back then was practical: the solar terms were used to decide where to insert the extra month a lunisolar calendar needs every few years.
A few of the names are still in everyday use:
- Risshun, “beginning of spring”, around 4 February
- Shunbun, the spring equinox, around 20 March
- Geshi, the summer solstice, around 21 June
- Risshū, “beginning of autumn”, around 7 August
- Tōji, the winter solstice, around 22 December
- Daikan, “great cold”, around 20 January
Notice that spring “begins” in early February, when much of Japan is still cold. In the traditional reckoning the solstices and equinoxes sit in the middle of their seasons rather than at the start, so the year turns earlier than a modern Western calendar would suggest.
The 72 kō: five-day microseasons
Each of the 24 terms is split again into three kō, giving 72 periods of about five days. Their names describe something happening in nature: a bird, an insect, a plant, the weather.
The original list was Chinese, and some of its entries are more folklore than observation (one claims that pheasants enter the sea and turn into giant clams). In the Edo period the list was rewritten to fit Japan’s climate. The astronomer Shibukawa Shunkai, who also produced the Jōkyō calendar adopted in 1685, worked on the revision with other calendar scholars, and the version most often quoted today comes from an almanac published in 1874.
Some of the Japanese microseasons:
- Harukaze kōri o toku (early February): the east wind melts the ice.
- Tsubame kitaru (early April): swallows arrive from the south.
- Kusaretaru kusa hotaru to naru (mid-June): rotten grass becomes fireflies, an old belief about where fireflies came from that survived as a poetic image.
- Kusa no tsuyu shiroshi (early September): dew glistens white on the grass.
- Momiji tsuta kibamu (early November): maples and ivy turn color.
- Niji kakurete miezu (late November): rainbows hide.
- Yuki watarite mugi izuru (around New Year): wheat sprouts beneath the snow.
The dates shift slightly from year to year because they follow the solar terms. What matters is the scale. Five days is short enough that you can actually notice the change the name describes, which is the whole point.
Kigo: how haiku carry a season
The same attention to the seasons runs through Japanese poetry. The Man’yōshū, the oldest surviving anthology, compiled in the eighth century, already had sections devoted to the seasons. The Kokinshū of around 905, the first anthology made by imperial order, was the first to organize itself into seasonal and love poems, and the primacy of seasonal poems has lasted ever since.
Linked verse made the seasons a formal rule. In renga, the long collaborative poems written in sequence, the opening stanza (hokku) had to include a reference to the season. When the hokku later broke away and became the haiku, the rule came with it, in the form of the kigo or season word.
A kigo can be obvious, like cherry blossoms for spring or sunflowers for summer. It can also be subtle. The moon is an autumn word even though it is visible all year: autumn nights are long but still warm enough to sit outside and look at it. In Matsuo Bashō’s famous haiku about an old pond, the season word is the frog (kawazu), a spring kigo, even though the poem is really about the sound of the water.
Poets look season words up in a saijiki, a kind of seasonal almanac that lists each kigo with a description, related words and example poems. Entries are grouped by season and then by subject (the sky, the earth, human activities, festivals, animals, plants), and modern saijiki add a separate section for the New Year. The seasonal sense of classical kigo is based on the region between Kyoto and Tokyo, where most classical literature was written, and a few kigo still go back to the old Chinese microseasons.
How the seasons show up in Japanese design
The same instinct appears far outside poetry. Restaurants talk about shun, the short peak season of an ingredient, and menus change to follow it. Confectioners make seasonal sweets that exist for a few weeks. In a traditional room, the scroll and flowers displayed in the tokonoma alcove are chosen to suit the time of year. Even mass-market products follow the calendar, with cherry blossom packaging in spring and maple leaves in autumn.
The common thread is that the season is not a backdrop. It is part of the design brief, and changing things with the season is treated as a sign of attention rather than as redecorating.
Bringing the seasonal rhythm into your space
You do not need a tatami room to borrow the idea. A few low-effort ways:
Change your wallpaper with the solar terms. That is roughly every two weeks, often enough to notice and rare enough to stay effortless. Some pairings from the themes on this site:
- Spring: cherry blossom path and girl with sakura umbrella
- Early summer and the rainy season: rainy porch
- High summer: rice fields in summer and, for evenings, lantern festival night
- Autumn: autumn maple village
- Winter: snowy mountain village and winter onsen
Keep one seasonal object on your desk. A branch, a stone, a small bowl of fruit, a postcard. Swap it when the season turns. One object is enough; the point is the change, not the collection.
Look up the current microseason. Note its name somewhere you will see it, then actually look for the thing it describes. In most places the swallows, dew or first frost will not match the Japanese dates exactly, which is part of the fun: you start noticing your own local calendar.
Try a seasonal haiku. Pick one thing you noticed this week, from where you actually live (the first cold morning, a smell of rain on hot pavement, the light at 5 pm), and write three short lines around it. Do not worry about counting syllables; English haiku poets often don’t. The season word does most of the work, and the exercise trains exactly the kind of attention the microseasons are about.
Mind your hemisphere. If you live in the southern hemisphere, as the person who runs this site does in Argentina, shift everything by about six months. Cherry blossom wallpapers in September and snow scenes in July will feel right; the reverse will not.
If you want to go further into the ideas behind this, the guide to wabi-sabi, mono no aware and ma covers the aesthetics of impermanence, and cherry blossoms through 1,000 years of Japanese art follows the most famous seasonal symbol of all from Heian poetry to the present.
Sources
- National Diet Library, Japan. 二十四節気 (The 24 solar terms). The Japanese Calendar online exhibition, in Japanese.
- National Astronomical Observatory of Japan, Ephemeris Computation Office. 二十四節気 (glossary entry). In Japanese.
- Higginson, W. J. (1996). The Haiku Seasons: Poetry of the Natural World. Kodansha International.
- Wikipedia contributors. 七十二候 (The 72 microseasons) (Japanese Wikipedia), Solar term, Kigo, Saijiki and Kokin Wakashū. Accessed October 2026.
