A Local Perspective on Life in Tsukuba, Ibaraki, Japan.

The Fascinating Evolution of Children`s Day ( Kodomo no Hi) in a year (2010) in which the rain has kept Ibaraki`s awesome CARP STREAMERS ( koi nobori) mostly out of sight

Typical of this rainy April- a carp streamer pole stands tall but lonely, without its majestic carp

Lovers of traditional Japanese culture usually look forward to April in Ibaraki. After the excitement of HANAMI ( Cherry blossom parties) has died down, there are the amazingly extravagant carp streamers ( koi nobori, which are raised up at  the homes of families with boys), to be admired, and photographed.

Taking carp streamers of of the rain- near Lake Kasumigaura

This year, however, with its unseasonably rainy ( and snowy!) weather, these beautiful and highly anticipated festive decorations which usually characterize our  spring village-scapes, have mostly been kept safe and dry in their boxes.

Well, the rain must stop at some point, right? And when/if it does, before May 5th, you are sure to see Ibaraki`s abundant and very large and colorful koi nobori waving proudly against the blue sky. It is quite a spectacle!

Let me tell you a little about how this, and other customs related to what is now called Children`s Day ( Kodomo no Hi) have evolved.

Carp streamers ( koi nobori) above nanohana and peach blossoms ( Koga, Ibaraki)

When looking into the origins of various elements of Japanese culture, one often finds dual or multiple roots. Even beginning students of The Japanese language are confronted with this fact  as they soon learn that there are two or more ways of reading kanji characters. There are even two ways of counting, the more purely Japanese way- hitotsu, futatsu, mitsu… and then the one based on the Chinese, ichi, ni, san.

It is especially interesting to keep this in mind when discussing Japan’s calendar of traditional annual events.This month’s standout special day is Children’s Day (子供の日, kodomo no hi) which has come to involve a fantastic array of festive decorations and  foods. Most notably, there are the carp streamers (鯉のぼり), which can be seen proudly flapping in the wind (in this part of Japan, we are lucky to be able to see especially large and elaborate ones) or displayed at shops and shrines. Inside people’s homes, or at restaurants and hotels we can see the armor or warrior dolls (Go-gatsu ningyo) which have been put on display.

Carp Streamers (koi Nobori)near Lake Kasumigaura Carp Streamers (koi Nobori)near Lake Kasumigaura 


Now, much less commonly, you can see a plant called shobu (菖蒲, this is a relative of the yam and NOT the  iris – the flower whose name has the same pronunciation and the same Kanji character!) )  on sale for use in the bath, and even more rarely in this part of Japan (though you can still sometimes see it), placed on roofs, along with some mugwort (蓬,yomogi). At wagashiya (Japanese sweet shops) and convenience stores, kashiwamochi and chimaki
are on sale, as the special sweets of the season.

What does all this have to do with Children’s Day?

First let me say something about Japanese festive days in general. Certain days were recognized by the ancient Chinese as being pivotal seasonal markers. These came to be known as sekku (節句)
when adopted by the Japanese. To mark the seasonal changes, each sekku involved eating certain foods and displaying certain decorations. In those times the significance of these was usually one of keeping away bad luck or ritual protection.

The major sekku which are still widely celebrated in Japan are:

January 7: Nanakusa (seven herbs) no Sekku
March 3: Momo (peach) no Sekku
May 5: Tango no Sekku, or Shobu (calamis) no Sekku
July 7: Tanabata
September 9: Kiku (chrysanthemum) no Sekku

(It is interesting to note that the Chinese, and subsequently the Japane are fond of ODD NUMBERED days and months)

It now being May, this month’s festive day is of course, Tango no Sekku, which is now known as the national holiday, Children’s Day. However, since this day has been recognized as being special since ancient times, there have been many meanings connected to it which have changed over the generations.

If you ask a Japanese friend about the significance of Children’s Day, they will explain that it is a day to celebrate boys and for families with boys to pray for their healthy growth and success. This goes in tandem with March’s Momo no Sekku which is a celebration of girls. They will also explain that carp streamers symbolize strength and perseverance.

The story of Tango no Sekku, however, is much more complicated than this and its history and the origin of its customs are now unfamiliar even to most Japanese. In ancient Japan (and still today), this is the season for planting rice. To pray for abundant crops and fertility in general and remove impurities from the village young women (早乙女, saotome) would spend a day isolated in a special women’s huts called onna no ie (女の家). This hut would be covered with irises and mugwort, which in ancient China were believed to have purifying powers (because of their strong smells). Remnant features of this ancient practice  can be seen surviving in the Heisanbo Festival held each May 5th at a small Kashima Shrine in Dejima, on the shore of Lake Kasumigaura.

In the Nara Period (710-794), the Japanese would decorate themselves with garlands of shobu and later in the Heian Period it was common (and still is) to decorate homes with these protective plants. At this time tall poles would also be set up by rice fields to welcome the God of Fertility.

Shobu (calamis) Stems and Mugwort (yomogi) On The Roof Of An Old Samurai Residence In Sakura City, Chiba

This photo shows shobu (calamis) stems and mugwort (yomogi) on the roof of one of the old samurai residences which are open to the public, in Sakura City, Chiba.

Later when Japan came under military rule, the Japanese name for the plant  shobu, came to held significant for its homonym, 尚武, shobu, which means reverence for martial arts. Thus, shobu has remained a part of Tango no Sekku throughout the generations and many Japanese still use it in their baths on this day for driving away evil and fortifying the body. It is surprising that most Japanese today confuse the traditional shobu with HANA SHOBU, which are irises. These extremely beautiful puple flowers can often be seen as INCORRECT sympols of Tango no Sekku at shops, etc.

 It was during the years of military rule that Tango no Sekku came to be associated with boys. One possible explanation for this can be that it had originally been a day to isolate women, and that left the boys to be celebrated!

Kashiwa mochi with the leaf unwrapped

Kashiwamochi is a pounded rice cake wrapped in the leaf of a Japanese oak. Eating this sweet in this season is an original Japanese custom and signifies the connection between generations, as these trees don’t lose their leaves until fresh leaves appear!

Kashiwa mochi

Eating chimaki, a conically shaped paste wrapped tightly in leaves, is a custom which originates in China. May 5th in China, is the memorial day of the great poet scholar Qu Yuan (屈原, read Kutsugen in Japanese) who was famed for his loyalty. On the 5th day of the 5th month, men would throw offerings into rivers (he drowned in one)
in his honor. At one point, many men at different locations dreamed that it would be better to wrap these offerings in purifying leaves. This became standard practice, and is now common today in Japan.

Raising carp streamers probably is a continuation of the native practice of setting up poles near the rice fields to welcome the rice god. Since Tango no Sekku came to be a day of celebrating boys, Japanese in the Edo Period (1600-1868) adopted the carp as a symbol of success. This is because of the ancient Chinese story of the carp struggling upriver and transforming into a dragon.

Another interesting reason for the samurai to have admired carp was the fact that this powerful fish, struggles desperately when caught, but when placed on the cutting board, it resigns itself to its fate, and dies with what the Japanese warrior class thought to be DIGNITY.

This custom spread throughout Japan and can especially be enjoyed in Ibaraki where farmers often display fantastic and very expensive koi nobori sets to celebrate their male offspring. For those who live in smaller abodes there are appropriately-sized streamers and even tiny origami or cloth carp.

My Own Go-Gatsu Ningyo With Kashiwa-Mochi and ChimakiFinally, there are the dolls and armour which are displayed. Grandparents often spend thousands of dollars on a display for their grandsons, though if you want some dolls for yourself you can get the
same exact dolls for a song at second hand shops (since many Japanese would not buy or are even afraid of used dolls!). These dolls became popular in the late Edo Period as emulating the Samurai class was all the rage for the merchants and then farmers. These dolls and armour are displayed to pray for boys success and health and can be found in a myriad of forms.

A Tsukuba Spring- Carp streamers and the HII rocket at the Expo Center

After the war, since the day had been associated with warriors, the name was changed to the more egalitarian Chidren’s Day, though girls and boys are still actually celebrated separately.

There are many other, more obscure decorations for this season, but I have written too much already, so go search them out for yourselves.

for an interesting way to spend Childrens Day, see my article-


or head out to the curious and very rustic Heisanbo Festival –



  • alice says:

    I read your site. I first thought it is iris from many reliable sources. Even this acclaimd Edward Moreno translated it from the Japanese version that shobu is iris. http://www.discovernikkei.org/ja/journal/article/3412/
    The kanji for shobu is sweet calamus. One species of Japanese iris (not the “ayame”) is hana shobu. Perhaps that’s the reason that causes the confusion.
    I think the site below is more reliable.
    I am baffled as I saw I see some Japanese use iris to decorate along with the gogatsu ningyo. I wonder why. Have you come across that?

  • alice says:

    Sorry, I forgot to delete ‘I see’ before I clicked on the sent button.

  • Avi Landau says:

    Hello Alice. Thank you for reading Tsukublog, and thanks even more for writing in your comments.
    It IS curious that so many who write about Japan in English, even the greatest names in the field of Japanese Studies, use misleading and completely mistaken translations.

    Why is this?

    Well, for one thing Japanese culture is sometimes just too complicated to clearly explain all the details in just a short essay.
    For example the excellent explantion of the history of KODOMO NO HI ( Children`s Day),on the Kyoto-Shimazu link which you sent to me, very incorrectly states that the Chinese ( and later the Japanese) celebrated a SEKKU ( seasonal change day) on the Fifth of May,
    This is a very misleading error. The Chinese did not follow the Gregorian Calendar and neither did the Japanese ( until 1872). A correct explanation would be to say the fifth day of the fifth month of the traditonal calendar ( which usually falls about one month later than May 5th!).

    Ive written about this problem here:

    As for the names of plants and birds, what seems to have happened is that the early great Japanese to English translators
    put more emphasis on aethetics than on scientific accuracy, using beautiful sounding English names when the true names were obscure or unpleasant sounding: for example nightingale instead of Japanese Bush Warbler or Iris instead of calamis!

    I have also written about this problem regarding the very misleading use of the name Hollyhock for the important Japanese plant AOI.


    The situation is regretable. There ARE so many excellent sources which, as you point out, use the word iris for the plant SHOBU (acorus calamis) in explanantions of Tango no sekku customs.

    Completely unrelated to the IRIS ( ayame, or hanashobu), this flowers was believed by the ancient Chinese to have the power to drive away misfortune ( because of its strong smell). It was used by the Japanese on the fifth day of the fifth month in various ways: put up on the eaves, wrapped around the waist, put under the pillow. drunk in a liquor, etc. This was all done with the intention of keeping healthy and lucky.

    One very difficult point for students of Japanese (as you point out) is that the Chinese characters can be the same for shobu and ayame AND that originally the plant acorus calamus was probably pronounced AYAME in Japanese!

    It is not strange that IRISES are also used as a popular decoration for KODOMO NO HI.

    First, they are extremely beautiful ( my favorite) flowers of the season, and their name HANA SHOBU is a homophone for SHOBU, which can mean martial spirit or battle ( with different characters, the theme which was promoted by the samurai class which made TANGO NO SEKKU in a day to celebrate their sons.

    In fact Alice, many or most Japanese today, probably do not even know that the SHOBU ( calamis) used for SHOBU-YU ( shobu baths) and to be put on the eaves are not HANA-SHOBU ( irises)

    Well, I hope I ve answered you question. Ive got to run off now to sing at the Tsukuba Festival.

    Hope to hear from you again!

    Avi Landau

  • alice says:

    Avi, thanks for enlightening me further. In both sites that I quoted, just like shobu and hana-shobu, it could be that the sechie【節会 for seasonal court banguet) which I think is rarely used now is misunderstood for sekku (節句 ・ 節供 for seasonal festival), as the first kanji of both words are the same.
    If I had not read your comments below your post ‘Tango no Sekku over ages), I would have thought it was iris. Perhaps it’s better for you to ammend the iris part of that post to avoid confusion.
    One more thing about flowers while I was reading your posts on Momo no sekku and hollycock, how can I tell the difference between peach blossoms and sakura. I can tell the difference between ume and sakura by the bark of the trees. Sakura trees have horizontal striped like barks on the trunks and branches. I once came across bright pink blossoms with many petals which looked like a kind of sakura (just before the sakura season or around sakura season), but a Japanese couple told me that it was peach. I examined the barks of that tree and it had the same stripe-like barks.
    Could you enlighten me on this? Thanks a lot.

    • Abe says:

      Hi, Alice

      The bark of both sakura and momo have lenticels (having a function conducting air between tree and the air), which seem horizontal stripes. But the bark of momo is vertically cracked well. Then, the horizontal stripes become sometimes unclear. The bark of sakura is not cracked. You know, the barks of some of sakura species (especially Ohyama zakura) are utilized for handicraft, because of its beautiful pattern of lenticels and smoothness (kaba-zaiku).

      • alice says:

        Thank you Prof. Abe. Yes, I noticed the cracks and stripes in older peach trees. The barks looked like a cross between a ume and a sakura tree. As for younger ones, they don’t have the cracks yet. By the way, how can I tell the difference in colour or shapes between peach blossoms and the sakura with many petals species like Kanzan and Ichiyo? When does peach blossoms bloom? After or before somei yoshino sakura? Is there a shiradare momo species? I saw a white weeping one after the someiyoshino sakura season is over but the barks of that tree are cracked.

      • Abe says:


        Flowers of peach, ume and apricot doesn’t have stalk, but sakura and plum have. When you eat their fruits, you can realize the difference. Flower season of momo is bit later than someiyoshino (A literature says it is mid April). I found out some cultivars of weeping momo. I am not so familiar with momo, but I found out weeping momo with white flowers in internet (http://blogs.yahoo.co.jp/tanigutiosakajp/24302652.html). I think the tree that you saw can be momo.

  • alice says:

    Oh, I checked the iris and calamus out with a Japanese friend who had taken shobu-yu before when she was a child. She said it is shobu, not iris. To confirm, I pluck a small part of two species of iris and smelled them – no fragrant at all.

  • alice says:

    Thank you Prof. Abe. I wish I could that white weeping peach tree for you to see. By the way, all ume (Japanese apricot) has five petals, right?

  • alice says:

    I mean I wish I could post a picture of that white weeping peach tree for you to see.

  • Abe says:

    Hi, Alice
    Some cultivers of ume have flowers with more than 5 petals. I have a photo of that. In Japanese, flowers with a bunch of petals are called “yae”. Then, you can say yae-sakura, yae-ume, yae-momo and etc.
    I am very happy if I can see your photo. But, I am not sure how I can get your photo. Can you upload it somewhere in internet? Anyway, I can’t see the internet until the next month, because, I am going into deep in mountains in Japan for my business.

  • alice says:

    Thanks again Prof. Abe for the information. When you said: “But the bark of momo is vertically cracked well. Then, the horizontal stripes become sometimes unclear”, do you mean that the barks of the momo sort of crack as if they are peeling off? I observed that there were the cracks and also some peeling structures on that pink momo tree I mentioned.