Sometimes that's all it takes. If you can't find them at garden centers, check your gardening catalogs. Several brands are available of lightweight spun or woven fabric that can be put directly on top of plants to form a barrier against insects. They let in light, air, and moisture, but must be removed when the temperature reaches into the high 80s, or when flowering plants need insects for pollination. Yellow traps attract thrips and whiteflies.
Red traps lure apple maggot flies.
Pheromone lures that drive certain bugs crazy, such as codling moths and apple maggots, will boost your success with some traps. Flea beetles might leave your eggplants alone if you plant radishes nearby, a plant they are particularly fond of. The bright yellow-orange blossoms of calendula are frequently the first place you'll find cucumber beetles and blister beetles. They make an easy target for hand picking while they are engrossed in these brilliant flowers, especially on cool mornings when beetles are sluggish. The diatom injure sow and pill bugs and many other types of insect larvae.