Birds, ladybugs and praying mantises are the gardener’s best friends when it comes to insect control. Birds can be encouraged into the garden by providing a feeder, a birdbath, or by providing plants that grow berries for them to eat.
Ladybugs are now for sale by the pint, quart or gallon. The average-sized garden can get by on a quart or less, as there will be about 25,000 to 30,000 bugs per quart. The cost is generally less than five dollars a quart. The average adult ladybug consumes between 40 and 50 aphids a day.
Praying mantis cases are also available and each one hatches up to 400 young. The cost is rather nominal for a case. A few gardeners have reported that this insect disappears rather rapidly from the garden, so you might want to experiment with just a few to begin with. They will eat any insect they can catch.