I love Chocolate Mint because the leaf is so tender and there is no chocolate taste (just a bit of a chocolate smell). I used to grow it all along the back of the house where it didn’t matter if it spread into the grass. Then we built a deck over that area so I rooted a bunch and moved them to the back of the shed, same exposure and it is thriving there as well. It gets afternoon sun and is facing west. The new location has a bit more shade from neighbors’ trees but it seems to be doing fine. I think growing mint next to grass with no barrier is just fine as it is fun to mow over it when it spreads because it smells so good and that is control enough for me. This is my fourth mint patch that I’ve handled like this and I still feel it is fine. In other words, the “dangers” of mint are vastly over-rated as long one puts it next to a turf like area instead of next to a “garden” and is not obsessive about grass being pure.