Yellow sticky traps are used both to monitor whitefly populations and to help suppress populations. Monitoring is the most common use, to detect movement of whiteflies into a greenhouse or increases in populations. For whitefly control, place many sticky tape or other traps around the planting. The small parasitic wasp, Encarsia Formosa , has long been used as a biological control for greenhouse whitefly. It develops within the whitefly nymphs.
Young whiteflies turn black and die in several days.
72 degrees F. Many Garden catalogs carry whitefly parasites. More recently, another parasitic wasp has been marketed, Eretmocerous californicus . It appears to have some advantages over Encarsia formosa . This occurs when the whitefly nymphs are punctured with the wasps' ovipositors. Instead of laying an egg, the adult feeds on blood from the wound.