Since planting five years ago I get several seedlings each year, in thick clay. I just pull what I don't want and leave the rest. Love the smell of it, and my daughter and nephews would never forgive me if I got rid of their favorite "mint" plant. I had it in the flower garden originally but recently moved it to the herb garden in a shadier spot with much thinner, drier soil, and it's doing just as well.
