Calamintha nepeta

I have planted some years ago Calamintha nepeta on my fathers grave. It is a bit risky because it spreads easily. But I have also learned that the spread begins only when sharing it. So I will not do so. When it gets too big for the grave, I will  dig up the whole plant. I want to keep it so far because the flower is so sheer and beautiful and always has lots of bumblebees, wasps and flies eating there.