Yes, I would say put it in an area of your yard that you don't mind it spreading. However, mine is basically in the same place as it always was, but we mow up to it! It makes a fine border for a lawn, and mine is growing on the north side of the house in the shade. So I think it in the south of the United States, it appreciates some shelter from the sun.
RE: Lemon Balm - Herb Of And Peace And Tranquility