Because of its brilliantly colorful but short blooming season of about 1 to 2 weeks, the Japanese cherry blossom has come to symbolize the beauty and the transience of life. The cherry blossom is also associated with Japanese nationalism and the military as a symbol of a loyal samurai who fell while serving his emperor. This belief led to the practice of pilots painting cherry blossoms on the sides of Japanese warplanes before Kamikaze missions during World War II.
In Japan, "hanami" refers to the traditional custom of people gathering to enjoy the transient beauty of cherry blossoms during their short blooming season. In modern Japan, the weather bureau announces the cherry blossom blooming season in "sakura-zensen" forecasts, the literal meaning of which is "cherry blossom front." These forecasts are closely watched so that gatherings can be planned accordingly. Nighttime viewings are called "yozakura" and are accompanied by paper lanterns specifically made for the occasion. Attended by many younger people, the nighttime festivals usually cause older celebrants to shy away because of the noise and crowds.
The tradition of hanami is believed to have started in Japan in the 8th century during the Nara Period with the viewing of plum blossoms. Cherry blossoms attracted greater attention of the Japanese during the Heian Period, which lasted from 794 to 1185. Since that time, the custom of hanami has become associated primarily with cherry blossoms.