Make sure that gardens don't mound new dirt over treated soil next to the foundation or piers. Avoid using mulch in gardens next to the house. Swarming season is between April and July. Seeing a swarm near your home or even finding a few of the bugs in your house only means you live near a nest. The swarmers are attracted to light.
Swarms coming from inside the house, garage or other structure are a sign of infestation.
But don't panic. It's a good idea to have an inspection annually. In fact, you should be doing your own checks more frequently - at least once every three months. Walk around the foundation, looking for mud trails, rotted wood and moisture problems. Rainstorms are a good time to crawl into the attic with a flashlight and check for leaks there.