ichidan verb
begin to bloom; start flowering
Used for flowers beginning to open. A straightforward compound of 咲く (to bloom) and 始める (to begin).
桜が咲き始める頃、公園はとても賑わう。
When the cherry blossoms start to bloom, the park gets very lively.
庭のチューリップが咲き始めた。
The tulips in the garden have begun to bloom.