Wasps should zap those pesky pests

My plants are infested with whitefly. What can I Simon, Exeter DAVID: Whitefly can appear in late autumn if it’s warm. The first frosts of November should kill off any infestations outside. If any remain in glasshouses or indoors, consider introducing Encarsia formosa, a tiny parasitic wasp available via mail order from biological control suppliers. These wasps lay eggs inside the whitefly and quickly get rid of the problem.