I started getting several ant hills around my yard here in the mountains, with some in or next to my garden. One fairly large hill was right next to my medicinal herb garden and I wouldn't doubt if the ants made off the seeds I planted since almost nothing I seeded came up. While ants are good at aerating the soil, the thousands of ants were getting to be a bit too much for me.
I wanted a completely organic method of getting rid of the ants. Some articles mentioned Borax or diatomaceous earth, yet those could also kill beneficial insects. On one gardening forum, someone mentioned grits. Yes, corn grits, aka cornmeal, aka polenta. I thought "If the gophers like garlic and Italian food, maybe the ants will like some polenta!"
The theory is that the ants will take the corn meal into their mounds, eat it, and when it expands in their stomachs, they will... umm, explode! So I gave it a try and tossed a handful of cornmeal on each mound, and sure enough they eagerly brought most of the cornmeal into their mounds. Within a day or two, the ant activity had reduced by probably 90%. A week or so later I am seeing very few if any ants near the mounds that were once crawling with thousands of ants.
Want to control your ant problems naturally? Make them a nice Italian meal of polenta!