Raising tomato plants requires time and care--don't let that work go to waste because ants decide they want to take over. Destroying these pests is simple enough, but doing so while protecting your tomato plant is another story. Though this may seem like an impossible chore, you may be pleasantly surprised at how quickly and effectively ants can be evicted from your tomato plants with little more than a few things you may already have around the house
Sprinkle cornmeal around your tomato plant. The ants will become distracted by the free food you left out for them and will busy themselves collecting it and taking it home for dinner. They won't be able to digest it, though, so it will nearly always kill them.
Wrap tape with the sticky side facing out around planters and pots that contain tomato plants. As the ants begin to climb up to your plants they won't get very far. Replace the tape as often as you would like, to eliminate the now-stationary ants.
Cut oranges in half and place them around your tomato plants. Ants will chow down, and so will the birds that will swoop down and take the orange slices, ants and all.
Spray ant hills with vinegar or sprinkle cayenne pepper liberally over their home. These smells are awful to ants and if you keep at it, they will eventually find a place that smells better--hopefully far away from your yard.
Fill a spray bottle with water and add dish soap to make it sudsy. Spray ants on and around your tomato plants to kill them. Over time ants will get the hint and won't come back.