I've tried a couple of different insecticides on white flies, but the YELLOW white fly traps worked miraculously! I have a friend who works in a greenhouse. He was kind enough one year to start a bunch of seeds for me in a spare corner of the greenhouse. Well, commercial greenhouses can be prime breeding ground for all manner of plant predators and, sure enough, my seedlings were covered with white flies when I brought them home. The traps cleaned them up (about 50 plants) in about a week! I had to change them often because the color would fade in the sunlight reducing the effectiveness. Good luck! Doug