Everyone says mint will take over, I have never been able to get it to grow, always dies on me in a few weeks.
Have you considered the soil you are planting the mint in? If its too chalky, the mint will die.
My gardening season this year, outside some veges, involves MOVING and transplanting current plants, shrubs and bushes. (Not as much fun as planting from seed or seedlings. But nice to see them take root and like their new locations.)