Cherry blossom is three weeks of it. Flip through the other forty-nine — and watch what's in bloom move up and down the country.
The calendar is the way in. Underneath it sits the ordinary thing — search, filter by month or flower, and open any of the 429 spots.

Photo Laitr Keiows (CC BY-SA 3.0) — via Wikimedia Commons
A national natural monument since 1934, standing beside a small Kannon hall among the farms of Kosa. Its single trunk, about 2.75 m round, splits into three limbs some 3.5 m up, and the scent of its flowers is said to carry 4 km. The tree is said to be over 770 years old.