Hanami is going out to places such as parks to enjoy leisurely while appreciating the beautifully bloomed cherry blossoms. The custom in Japan, in March and April when the cherry blossoms are in full bloom, is to do hanami with family, colleagues from work, or friends. People spread a mat under the cherry blossoms, drink sake, sing songs, and enjoy the coming of spring. In cities, viewing cherry trees in the evening is especially popular. Against the spring night sky, the beauty of the cherry blossoms in full bloom is abundantly emphasized.
via: Key Aspects of Japan