You can suppress the growth of dust mites by placing them in areas where you are concerned about dust mites breeding, such as inside pillowcases or under your futon. Rather than killing mites with neurotoxins, when the product comes into contact with the mites and ingests them, the mites become dehydrated, gradually weakening, and preventing the reproduction of mites. Dust mites appear all year round, but blood-sucking house mites are said to be at their peak from June to September.