Secret Flower Field

Walkthrough: Once back at the Odyssey Airship, you'll see an object descending onto the tower from above. Head back to the path that leads to Iron Road, using one of the Steam Gardeners' flowers to earn a speed boost. In the next area, the Piranha Plants have now been replaced by Sherms, the same that fire projectiles at Mario. Use Cappy to take capture and take control of one in order to defeat the other, and then destroy the entrance to the blocked building on the left.

Before going in the entrance, head around the corner to find more Uproots. Capture one and follow the path that leads to another nut, destroying it to obtain a Power Moon. The entrance you opened earlier will lead straight to Secret Flower Field, and once inside, pull the lever as the robot asks in order to receive a seed. Place it in the patch of grass next to the robot to have a beanstalk sprout, and then climb said beanstalk all the way to the next area, the Forest Charging Station. One the way up the beanstalk, you will also see more Purple Coins on one of the ledges.