This amazing midge was first characterized by researchers in Germany. It was a contaminant in an Aphidius trial. The trial was a failure because all of the Aphids disappeared. The researchers noted the presence of Aphildoletes midge and larvae but could not believe that they could be so effective. Subsequent experiments proved that Aphidoletes application is an excellent aphid control. When not cold stored, Aphidoletes has a tremendous searching ability, capable of finding individual Aphids within the crop. In our prevention method, only one release point per hectare of protected crop is needed for Aa to find single aphids.

Cycling both indoors and outdoors readily occurs if enough Aphids are present. Aphidoletes overwinter by diapause, triggered by short days. Diapause can be avoided in protected crops by supplementing with very low intensity light, such as adjacent street lights, walkway lights left on, LED garden walkway lights, or a string of Christmas lights suspended near the area.

The field or “garden” strategy is inoculating hot spots with an appropriate number of Aa. If enough aphids are present, Aa will multiply 20 fold after two or three weeks, spreading into adjacent plants and greenbelts. We find that outdoor applications are effective up to 5 years, after which, due to dilution, more Aphidoletes may be required.

We sell Aphidoletes in 5 packages:

1.  250 tray:  ideal size for hot spot treatment or prevention in an area of less than 2500 square meters, or in home gardens.

2.  250 Max vial: this is the simplest method. Just hang the vial near the hot spot and walk away. This product is well-suited for municipal trees and gardens where labor is at a premium.

3.  1000 tray: ideal size for preventative release program for an area of less than 10,000 square meters. As rates goes up, increase release points up to 8 per hectare.

4.  3000 tray: this tray is well suited for larger greenhouses or field crops. It allows an increase over the 1,000 sized tray without adding any more release points.

5.  5000 A-Bomb: this product was originally developed as a Whitefly control for extreme Bemisia hot spots in Poinsettia. It is economical and suited for outdoor release for crops such as Hop, Pecan, Apple, Berries etc.

Aphidoletes are effective against most Aphid species and Adelgids. Aphidoletes will also control Whitefly hot spots if there are no Aphids available for them. We have used them inundatively against the Potato Psyllid, where they feed on the juvenile stages, but they need to be placed in the hot spots as they cannot find the Psyllids by smell.

With the exception of the 250 Max Vial, all of the trays should be held at room temperature until the adults have emerged. This allows a simple number test and the trays are well-suited for mating.

Release strategies

  • Greenhouse prevention: place the open tray at a neutral release point, using this release point every time. It should be off the floor, and protected from watering sprays or direct sunlight. Usually placing it on top of an electrical panel works well, or bolting a flower pot on a post facing North, above the crop.
  • Outdoor inoculation: release an appropriate number in an aphid hot spot. Smaller, timed releases are more effective than one large release, but it will take longer to get the aphids under control. In extremely windy locations or when prevailing winds are constant, favour an upwind releases.

Aphidoletes adults are nocturnal, working at dusk. They can find single aphids from 200 feet away and lay their eggs either directly on the aphid or nearby. The larvae hatch from the egg within 24 hours and begin predation immediately, each killing about 200 aphids per day. After 10 days, they fall to the ground to pupate, re-emerging in about 14 days.

For more detailed release rates and general information, please see: