Encarsia formosa is a tiny parasitic wasp that parasitizes whiteflies. It was the first biological control agent developed for use in greenhouses. The whitefly species in a crop must be correctly identified to make sure it is a species that Encarsia can control and to determine the correct release rate.
The predatory beetle Delphastus avoids feeding on the whiteflies that have been parasitized byEncarsia. Delphastus adults also feed on whitefly eggs and can therefore be used with Encarsia. The predatory bug Dicyphus hesperus may be used with Encarsia. The parasitic wasp Eretmocerus californicus may also be used with Encarsia.
- Best use preventatively at roughly 0.1 per square foot before adult whiteflies are seen and 0.2 per square foot thereafter. Monitor on the lower leaves and look for black scales. When 90% present are black, reduce rate.
- Encarsia pupae are sold glued onto cards or as loose scales. For pupae on cards, it is important to hang the cards from lower leaves in the shade as Encarsia tend to fly upward. Avoid wetting them while watering. If there are hanging baskets in the greenhouses, some cards must be placed on the baskets, as well as on plants on benches. Do not attempt to use Encarsia if high whitefly populations are already established.
- Orders for E. formosa must be received by noon on Friday for shipment the following Wednesday, with exceptions for major holidays. Bulk discounts are available for large orders, please contact us for details. Beneficial insects are normally shipped by FedEx Ground within the state of Washington, and by FedEx Express elsewhere in the USA. Please contact us directly if you require a different method of shipping.