It depends where you are standing!
Near petablurg city[between odletown.But nearest to petablrug.]you can find him/her in a patch of grass.
Grass is a plant. A "large patch of grass" is a group of plants.
you use the pokerdadar when you stand in a patch of grass if you not stand on a patch of grass then it won't work
Because the acidity from the dog's urine kills the patch of grass they urinated in.
You have to find a patch of grass that shakes on its own. Go to that patch of grass, you will find often find Audino or Pansage.
In a patch of grass by it's self
go in a patch of grass!
A pasture.
After you get the national Pokedex, go to the cave that guy was blocking earlier. He should be gone. Once you get out of there go to the nearest patch of grass. Search for a while & you SHOULD find Gloom.
Go to Floaroama town and go to the right. Then go to the bridge and surf upwards until you get to the patch of grass but do not go there. Keep going up and stop at the patch of grass with the tall grass. There it is!
in the patch of grass on the way to subyshore.
Instead of flying to the nearest city, which makes it run away, walk or bike to its icon on poketch app Marker Map and look around in the nearest patch of tall grass. Mesprit often runs away, so be careful!