As nouns the difference between flower and hanami

is that flower is a colorful, conspicuous structure associated with angiosperms, frequently scented and attracting various insects, and which may or may not be used for sexual reproduction or flower can be something that flows, such as a river while hanami is the japanese custom of enjoying the beauty of flowers, usually cherry blossoms or plum blossoms, also known as "flower viewing".

As a verb flower

is to put forth blooms.