The answer to 'when to treat for flea' is that you should treat for fleas as soon as you notice an infestation in your home. Fleas can multiply quickly, so it's important to act fast to get the problem under control. The best time to treat for fleas is typically in the spring and summer when flea populations are at their peak, but you may need to treat year-round if you live in a warm climate.
When treating for fleas, it's important to focus on both your home and your pets. Vacuum and steam clean carpets, upholstery, and other areas where fleas may be hiding. Treat your pets with a flea medication recommended by your veterinarian. You may also need to treat your yard and outdoor areas to eliminate any flea eggs or larvae.