Last year our back flowerbed was overgrown with mint. In a sneaky land-grab maneuver, the mint had claimed territory from the rose, cone flower, lambs ear, and another plant that I don't know the name of. Here's a picture of the nameless thing.
While the mint maintained its stranglehold on the back flowerbed, all of its neighbors suffered. You'd expect nothing else of the rose and cone flower. They just lie down and take it. But lambs ear? It too is known to be invasive and tenacious. It can get out of hand and take over a garden, but lambs ear doesn't hold a candle to mint. Nope. It didn't stand a chance.
But ultimately the mint didn't stand a chance either. It had to contend against me. At about this time last year I decimated our mint crop. Three healthy patches of mint survived my pruning.
It was too late in the year for this measure to make a meaningful difference for the other plants. But this year my imposed restriction of the mint's territory has made a world of difference. Everything is blooming bigger and better, and I keep a watchful eye lest the mint revive its dreams of unchecked expansion.