What is Japan's national holiday?

Answer 1

Japan has many national holidays.

In late April, early May there is a week called Golden Week.
http://en.wikipedia.org/wiki/Golden_Week_%28Japan%29

In August, there is Obon.
http://gojapan.about.com/cs/japanesefestivals/a/obonfestival.htm

They also celebrate Christmas with their friends and New Years with their family.

Answer 2

Bonsai Day

Answer 3

Japanese national holidays, festivals and events

正月 (New Year) - 1-3 January
New Year is mainly a family celebration in Japan. People go back to their home towns or parents' home. As most shops and restaurants are exceptionally closed for 3 days, people prepare the traditional "o-setchi ryouri" (お節料理), eaten during this period.
成人の日 (Adult's Day) - 15 January
Celebration of the coming of age for boys and girls turning 20 that year. The coming of age symbolizes mainly the obtention of the right to buy cigarettes and alcohol legally. Ceremonies held at temples and shrines and girls wear special kimono for the occasion.
節分 (Setsubun) - 2 or 3 February
On the evening of the first day before the traditional beginning of Spring (立春 "risshun"), a brief rite called "mame-maki" (豆まき, literally "bean-throwing") is conducted at temples and shrines to drive away evil spirits and disease. It is especially popular with children.
バレンタインデー (Valentine's Day) - 14 February
Contrarily to Western customs, it is normally only women who offer presents on Valentine's day in Japan. It is usually chocolate and is not restricted to their boyfriend, husband, but to any men among friends or colleagues. The joke goes that as many Japanese men do not like sweets (including chocolate), women offer them to their husbands but eat them afterwards. The other reason is that men have to reciprocate twice what they have received one moth later, on White Day.
ひな祭り (Hina Matsuri) - 3 March
This festival is dedicated to (young) girls. Dolls representing an ancient Imperial couple are displayed in houses of unmarried girls to bring good fortune on them. The superstition has it that if dolls are not put back to their boxes before midnight, girls in the house will never marry.
ホワイトデー (White Day) - 14 March
A Japanese invention. As only women give presents on Valentine's Day, men should return the gesture one month later. It is also called "knicker's giving day", as some men buy panties to their woman. Again, that could be seen as a self-interested gesture, as men will enjoy their lady's wearing their gift.
花見 (Plum & Cherry Blossom Viewing) - February to April
Blossom viewing has been popular in Japan for over a thousand years. Cherry blossoms ("sakura" 桜) are the most popular and are one of the symbols of Japan. Hundreds of thousands of cherry trees have been planted all over Japan. Canals in cities like Tokyo are typically lined with them and rare are the parks that do not have their fair share of cherry trees.
Numerous companies and organization have been named after them, and "sakura" is also both a female given name and part of some family name '(Sakurai, Sakurajima, Sakuraoka...).

Plum trees ("ume" 梅) are the first to bloom in February, followed by peach trees ("momo" 桃) in March and the cherry trees late March to early April (or a few weeks later in Northern Japan).

彼岸 (Higan) - around 21 March and 21 September
Memorial services for the deceased are held at temples on the 7 days preceding the vernal and autumnal equinox. People visit their family graves during this period.
ゴールデンウイーク (Golden Week) - 29 April to 5 May
One of the 3 major holiday period for Japanese along with the New Year and Obon, the Golden Week was thus named because it includes 3 public holidays within on week. These are Green Day (緑の日, 29 April), Constitution day (憲法の日, 3 May) and Children's Day (子どもの日, 5 May). Depending on the year, these will be more or less conveniently combined with a weekend.
All flights and hotels are usually fully booked during the Golden Week and prices can increase up to 5-fold. It is best to avoid this period if you are planning to travel in Japan.

"Kodomo no hi" on 5 May is mostly dedicated to boys, rather than all children (girls have "Hina Matsuri"). Families with male children fly paper streamers of carps called "koinobori"(鯉幟), which symbolize healthy growth.

七夕祭り (Tanabata Matsuri or Star Festival) - 7 July
According the the Chinese legend, a princess and a shepherd fell in love, but were forbidden to meet, except for that day of the year (tanabata), when the two stars Kengyu (the shepherd) and Shokujo (the princess) meet in the Milky Way.
Children write poems or wishes on streamers of paper and attach them on special tanabata trees. Tanabata is celebrated on 7 August in some areas of Japan (e.g. Sendai).

お盆 (O-Bon or Lantern Festival) - 13-16 August
Obon is a Buddhist festival in homage to the spirits of the ancestors. It is said that the spirits return to earth during Obon, and lanterns are lit in front of houses to show them the way to their family. Lanterns are then floated on rivers to indicate the way back to the underworld - although the practice is now forbidden in big cities to avoid pollution.
Obon is normally held mid-August, but sometimes also mid-July. Many people living in cities return to their hometowns. It is also a busy vacation period, like the New Year and Golden Week, although this applies to all August, not just Obon itself.

ハローウイーン (Halloween) - 31 October
Halloween is also celebrated by Japanese youths nowadays, though it is pretty much restricted to wearing costumes in nightclubs in areas such as Roppongi or Shibuya in Tokyo. Children do not go from door to door asking for candies.
七五三祭り (Shichi-Go-San or 7-5-3 Festival) - 15 November
Shichigosan is the traditional custom of taking boys aged 3 and 5 and girls aged 3 and 7 to be blessed at the local Shinto shrine to thank for their good health and pray for future blessings. Children are dressed up in colourful kimonos.
クリスマス (Christmas) - 25 December
All Japanese know Christmas, and decorations in supermarkets and department stores are as obvious as in any Western country, if not more. Some Japanese people buy a Xmas tree and decorate their house, but they are not the majority.
Christmas is just like another Valentine's Day for many. It is common for (young) couples to go have a romantic dinner or go to the cinema. Japanese do not have a family party like Westerners. This is reserved for the New Year.

Public Holidays
Japan has 13 public holidays. When one of them falls on a Sunday, it is reported to the following Monday.

1 January - 元日 (New Year's Day)
Second Monday of January - 成人の日 (Adult's Day)
11 February - 建国記念の日 (National Foundation Day)
21 March (approx.) - 春分の日 (Vernal Equinox Day)
29 April - 緑の日 (Green Day)
3 May - 憲法記念日 (Constitution Day)
5 May - 子どもの日 (Children's Day)
15 September - 敬老の日 (Respect-for-the-Aged Day)
22 September (approx.) - 秋分の日 (Autumnal Equinox Day)
10 October - 体育の日 (Sports Day)
3 November - 文化の日 (Culture Day)
23 November - 勤労感謝の日 (Labour Thanksgiving Day)
23 December - 天皇誕生日 (Emperor's Birthday)

I hope this will help you

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