In a garden who owns which side to walls and fences?

If the walls or fence is within the property line of the owner, both sides are owned by the property owner. Depending on your city codes, in fla.... it has to be on the owners side of 6 inches.

Some states... if it's placed over onto your side, they have to move it, or I believe it becomes yours. Finished side of fence has to face neighbor's yard.