There is someone in every game (Move Deleter) talk to him and choose the move (Basic, TM, or HM) and they will forget it.
Usually these people are far into the game so you'll have to wait till you get there.
I cant think on the top of my head where they are all at, so you have to look though all the towns.
The easiest way to for a Pokemon to forget a HM is in Fuishca City. To the left of the Pokemon center are two houses, and in one of those houses, there is a Pokemon Move Deleter. Talk to him, and you can delete ANY move.
There is a move deleter who can make pokemon forget HM moves.
the hm move strength is found in the cave Rusturf tunnel
You can't get rid of HMs in heartgold.
You can just reteach it since HM are reusable.
If by delete a HM you mean get rid of said HM you can't. Otherwise if you want to get rid of an HM move a Pokemon has learned, go to the Move Deleter in Lilycove City. His house is to the left of the Lilycove Department Store.
You can't. The move deleter in Fuchsia city.
You can't get rid of boulders, you can only move them around and that's only with a Pokemon that knows the HM strength.
You can delete HM Moves via the Move Deleter, who is located in Canalave City.
U cant get rid of HM moves in any pokemon game
Go to the move deleter's house in fuschia city.
A HM is a move is a move that can be tought to as many Pokemon as you like but the Pokemon has to be able.
Talk to the Move Deleter. He always has a sign outside his house and is in a "Major" city.
In Fuchsia City, the Move Deleter lives in the house on the left of the Pokemon Center. He can make your Pokemon forget moves, including HM's.Go to fuschia city and head to the Pokemon center but enter the house right to the left of it inside is a guy who calls himself the move deleter choose the Pokemon you want to delete the HM move from choose the HM move and say YES to get rid of it.
He is in canalave city. To get there you need the HM surf. You can get it in celestic town. If you want to delete some moves, be ready to get rid of HM moves.
Yes. Go to Canalcave City and the move deleter will be in the second house to the left of the entrance.
defog is no longer a hm move but if you want to get rid of it go to the place with fog on your birthday