Tsubomi Hanasaki has a recurring dream in which a PreCure, Cure Moonlight, is defeated while trying to defend the legendary Tree of Hearts from the evil Professor Sabark and Dark PreCure, and sends the fairies Chypre and Coffret to find her replacement. Following this, Tsubomi moves to the town of Kibōgahana where she meets Erika Kurumi, who is a girl from her new school who tries to help the normally shy Tsubomi change her image. However, Tsubomi is put off by Erika's overly forward attitude, causing Erika to be chided by her older sister Momoka, who she is jealous of. While walking through the park, Tsubomi encounters Chypre and Coffret, who are being chased by a woman named Sasorina. Sasorina finds Erika at the park and steals her Heart Flower, which is wilting due to her jealousy towards Momoka, turning it into a Desertrian. Upon learning of the dream Tsubomi had about Cure Moonlight, the fairies choose her to become the next PreCure, Cure Blossom, and fight the Desertrian.