You can find plenty of pesticides that will kill ants around the house and yard. But what do you do when they build a huge mound in your vegetable garden? You can't use most of these pesticides around plants that you intend to eat. You can look for one that's labeled for use in a food garden, but an even safer approach is drenching the mound with a simple ingredient. It won't necessarily kill the ants, but it will move them away from your garden so that you can use more traditional pest treatments to get rid of them.
Wait for a sunny but cool day. The ants and their queen will move closer to the surface where the soil is warmer, according to PBS' The Victory Garden.
Pour white vinegar from the bottle directly into the center of the ant mound in your vegetable garden. Make sure the ground is saturated by the vinegar.
Pour a "barrier line" of vinegar around the vegetable garden or the vegetable plants themselves. Include areas of the garden where the ants have not yet penetrated.
Repeat the treatment if the ants simply move a few feet away from the original mound, but the new mound is still within your vegetable garden. Reapply the vinegar if it rains within 24 hours of application.