How to increase humidity in Pokémon Pokopia

You’ll need to increase the humidity in Pokémon Pokopia early in your adventure to restore the Withered Wasteland and earn the right to explore other regions. Professor Tangrowth is a bit vague about how you should go about doing that, though. While you will need to bust out the Water Gun ability a fair bit, there are easier ways to make the wasteland moist without having to water every patch of ground.