Safer"s Tomato & Vegetable Insect Killer utilizes the power of potassium salts of fatty acids (insecticidal soap). The potassium salts weaken the insect’s waxy protective outer shell. This results in dehydration, which causes them to die. Unlike traditional synthetic chemicals, it breaks down into its natural elements, leaving no residual impact on the environment. One application lasts up to 10 days, and the product can be applied up until the day of harvest.