The mint thing seems to work. We had some chocolate mint—think peppermint patty—escape in the greenhouse. As long as we leave it be around the pump, no fireants. Clean the greenhouse, pull the mint up, and in about 3 days we have fireants inside. The mint will grow back—it’s also escaped to the outside and grows all teh way down the side of the greenhouse and out into the grass. Smells great when teh guys mow!
I have mint confined to a planter. My wife likes fresh mint in her hot or iced tea. I told her the only way I was planting mint was if I could confine it! I watch it closely!