This page offers a guide on The Wilted Sunflowers, which is the 4th episode in Pinna Park.
Defeat the Snooza Koopas
Head along the beach towards the large green spotted eggs. When you shoot water at the eggs, the Snooza Koopas will wake up and try to attack you. When they jump up into the air, quickly run out of the way and they’ll fall and sink into the sand. Then, whilst they’re momentarily incapacitated, ground pound on them to defeat them. When you defeat a Snooza Koopa, a small patch of sunflowers will sprout and the Sunflower Kid nearby will bloom again!
There are five Snooza Koopas, and you’ll need to defeat all of them to restore the Sunflower Kids and then the Great Sunflower at the center. Each time you defeat a Snooza Koopa, the period of time that the Koopa is stuck in the sand reduces, so you’ll need to be quick with your ground pounds. When you’ve defeated all five Snooza Koopas, the Great Flower will give you a Shine Sprite as a reward.