Persuade beneficials birds to become residents in your yard or garden. Invite the birds to vist and take up residence. Birds comsume a large amount of insects as part or all of their diet, depending on the species. Martins can consume a kazillion (more or less) mosquitoes in a day. Put out birdseed in feeders, plant different types of plants to provide fruits, seeds, protection, and nesting sites for birds or hang nesting boxes. Be sure to supply a water source for them.
By providing birds with favorite flowers, water, and shelter, the will get your pest control problem under control and keep it that way. You won't need to spray anything that could also kill the beneficial insects.
Row covers, stiff plastic netting, or inset barrier fabric over plants or beds will keep the birds away from the crops you don't want them into.
To find out more about attracting birds, check out the places listed below.
Other beneficials to have around are spiders, toads, and some insects.
Spiders are one of the most effective insect predators. Don't disturb the webs and don't kill them. Mulching pathways and bare areas give the spiders extra protection. So stop being squemish about spiders and let them help you in your garden. If they come in my house, I just catch them and carry them out to the garden.
Toads and frogs are insect eaters. They don't like to go dry, so give them someplace where they can hide from the heat and stay moist. Make a flowerpot house for them by chipping a doorway in the rim of an old clay pot. Put the pot upside down somewhere in your garden. How's that for a welcome mat. They need water, too, so provide a source for them. I put an old hub cab near the flower pot. Works great.
Attract beneficial insects by letting their favorite wild and weedy plants grow. These undisturbed areas will provide homes for both insects and birds. You can also attract a wide range of predatory, parasitic, and beneficial insects by planting flower borders that are rich in nectar and pollen. Mix plantings throught the garden amoung the veggies. Some good things to plant are sweet alyssum, members of the parsley family (angelica, anise, caraway, carrots,cilantro, cumin, dill, and fennel), daisy family (asters, calendulas, cosmos, daisies, feverfew, goldenrod, marigolds, ornamental thistles, sunflowers, yarrow, zinnias). The flowers are what attract the insects so let some of your herbs flower.