It lays groups of eggs on the underside of leaves. The eggs hatch into small oval crawlers, which then settle down on the undersides of leaves and become scale-like. These insects spend about 4 days in an immobile pupal stage before becoming adults. About 5 weeks are required to complete the life cycle in the greenhouse. Yellow sticky traps are an effective way to monitor populations of whiteflies, and may even be attractive enough to reduce minor infestations.
Biological controls can be effective against whiteflies, especially in a greenhouse environment.
The predatory ladybeetle, Delphastus pusillus, specializes in whiteflies and feeds on all three whitefly species. The parasitoid, Encarsia formosa, can control the greenhouse whitefly in the greenhouse. Another parasitoid, Eretmocerus californicus, attacks all three species and can assist in controlling minor infestations in the greenhouse. Insecticidal soap or ultra-fine horticultural oil, which are among the compounds registered for control of this pest in Connecticut, sprayed on the undersides of leaves, can be used against whiteflies in the greenhouse or the field. Repeat applications of sprays will probably be needed because some stages in the life cycle are dormant and not affected by insecticides or other sprays.