The presence of whitefly is indicated by large amounts of sticky honeydew and sooty moulds on the upper surfaces of leaves, and by a yellow mottling where the whitefly have fed. Whitefly can transmit several plant viruses and infested plants suffer from a lack of vigour.

Tomatoes and cucumbers are usually most severely infested, although this pest will attack many other

common glasshouse and houseplants. One specific biological control product is available which is Encarsia.