Having ants invade your home through your dishwasher drain is a very common problem, especially in the winter when it gets colder outside. Luckily, there are a few steps that you can take before you call a professional pest control service to see if you can get the problem under control.
1. Pour Vinegar Down the Drain
The main reason why ants are invading your dishwasher is because they can smell the food that used to be on the plates that have been washed. The smell of this food is not totally masked by the smell of whatever dishwasher soap you are using. In order to further mask the smell, as well as sanitize your drain, pour vinegar down it. Pour at least a cup of vinegar down the drain.
Another reason why you want to use vinegar is because it's a natural pest control material. It's able to kill ants without harming any other creatures around your home, making it totally safe to use. By combining killing the ants that are currently coming up your drain with masking the smell of your dishwasher, ants will be significantly less likely to continue invading.
2. Clean Your Kitchen
When ants come into your home, they don't just stay in your dishwasher. They move into the rest of the kitchen where there is a ton of food for them to eat. Start by sanitizing everything. Get all food particles off your counters and floor, remove everything from your cabinets or pantry and get rid of any cereal or other food bits that might have fallen, and clean all surfaces in the cabinet before putting anything back. If you have kids that eat boxes of cereal or keep a lot of rice on hand, to make sure that nothing gets contaminated, invest in some airtight plastic containers. Pour anything that's boxed into the containers because plastic is much more difficult for ants to invade than cardboard. Kill any ants you see while you are cleaning.
3. Run the Dishwasher on Empty
After you've finished cleaning and have allowed the vinegar to move through your dishwasher's pipes, run the dishwasher again without putting anything in. This will rinse away any dead ants. If you're worried about contamination, consider rinsing citrus down the drain as well before running the dishwasher. A good option is lemon juice.
If you've tried these methods and they haven't helped, you will want to consider contacting a professional pest control service.