Small insects, especially aphids, can be controlled by spraying them with a garden hose. If you use this technique, be sure to spray the water onto the undersides of the leaves, where aphids feed. Trapping Some blueberry pests can be trapped using either visual attractants or baits. Leafhoppers and aphids are attracted to goldenrod yellow and can be caught on a yellow surface covered with a sticky substance. Use bait traps to trap adult blueberry maggots.
Ammonium carbonate is the attractant, and the flies are caught on surfaces coated with tangletrap.
There are several ways to design the traps. For one trap, start with a cottage cheese container. Place about 1 teaspoon of ammonium carbonate in paper and faster it to the bottom of the container, then coat the inside walls with tangletrap. Hang the trap upside-down from the foliage by a string fastened to the bottom of the container. If you paint the trap goldenrod yellow, it will be even more effective.