I didn't make it in time for cherry blossoms but, this is for you.
「桜の季節に間に合わなかったけど(贈り物は)私の気持ちです。」は英語で「I didn't make it in time for cherry blossoms but, this is for you.」という表現が一番自然だと思います。
桜の季節ーCherry blossom season
間に合わないーToo late for・Didn't meet
贈り物ーGift・Present
私の気持ちーMy feelings・My thanks