SAKURA

Cherry blossom

The cherry blossom is considered the national flower of Japan, and is central to the custom of hanami (flower viewing). In Japan, cherry blossoms symbolize clouds due to their characteristic of blooming en masse, and are considered an enduring metaphor for the ephemeral nature of life.

Text from en.wikipedia.org/wiki/Cherry_blossom

Utagawa Hiroshige, The Sumida River Embankment in Edo, 1858

Implicit reference
Explicit reference

Differently from the other flowers (Hana), sakura tends to be represented in anime because it conveys the particular meaning of ephemerality.