Many people think of ladybugs when they are looking for help with aphids, but these aphid predators offer much better control. Green Lacewings, for instance, are ferocious hunters of aphids. They have a seemingly endless appetite - they will consume an incredible number of aphids and then move on to other pest insects. Aphidoletes aphidimyza, on the other hand, stick with aphids. They imbed themselves in aphid colonies by laying their eggs there. Once they hatch, the ravenous larvae will begin preying upon adult aphids around them. Other aphid predators are parasitic wasps and search out aphid nymphs as a place to lay their eggs. When the wasp's eggs hatch inside the aphid nymph (which is dead at this point), the aphid hardens into a leathery brownish-grey mummy. Once the aphid parasite matures, it will chew a hole in the mummy and emerge. The beauty of buying aphid predators is that you can place them exactly where you need them so that they get right to the job of eliminating aphids.
All of these predators are most effective when applied before or at the time of infestation.
Aphelinus abdominalis: These parasitic wasps use aphid nymphs as a place to lay their eggs, but they also save some nymphs to use as a food source - the protein they provide helps the female wasp develop more eggs. Sold as mummies.
Aphidoletes aphidimyza: These predatory insects feed on over 60 species of aphids. Sold as pupae.
Aphidius colemani: These parasitic wasps can be used year-round in fields and greenhouses as it is not affected by short-day lengths. Sold as mummies.
Aphidius ervi : This species of parasitic wasps is highly effective against some of the larger aphid species, like Potato Aphids. Sold as a combination of mummies and adult aphid parasites.
Green Lacewing: These generalist predators hunt in their larval stage and will devour all manner of aphids as well as other common plant pests like mealybugs, spider mites, leafhoppers (in the nymph stage), moths (in the egg stage), scale, thrips and whiteflies. Sold as eggs or larvae.