Abstract: In a commercial semi-field trial in England, the predatory mite Typhlodromipsmontdorensis (Schicha) gave 97% control of Trialeurodes vaporariorum (Westwood) and 100%control of Thrips tabaci Lindeman larvae. Mites were applied to the plants in a preliminarycommercial formulation in proprietary paper sachets. From a single release point mites spreadfrom the top to the bottom of plants in large numbers, and the presence of all life stagesdemonstrates that they successfully established and bred on the plants. The peak mite populationrecorded on a single plant was 584 mites, of which 22% were eggs, 42% adults and 36%juveniles. Mites were present and easily visible amongst adult whiteflies in the heads of theplants.