Okay, you never heard of companion planting, the use of traps and netting to ward off all those uninvited guests in your garden. 
Companion plant gardening is the least expensive method because you have already invested in the plants and from there it is simply a matter of putting plants together that complement each other in repelling insects. 
Now is the time for the gardener to make a list of items that you want to grow and arrange them in your garden in such a manner that they protect each other.  This is companion planting!  Planting a variety of plants with the diversity needed that will reduce the threats from all types of pests and disease.
A good repellent is chives and it a great companion for tomatoes, carrots, and apples; besides, it is very tasty.  An added bonus with chives is that it attracts beneficial insects which assist one in reducing the pest population.
Cucumbers, cabbage, and other veggies are well protected from beetles, root files, vine borers and other pests by the tasty radish.  Plant these around your  plants and most pests will be repelled from having a meal on your meal ticket.
Like potatoes, a good companion plant is the onion.  This also holds true in the kitchen.
With a little research one can find a complete listing of companion plants that go together and plants that are not so compatible with each other.
Beneficial insects are a big help in controlling garden destructive pests and how does one attract these knights in shinning armor?  Herbs such as borage, dill, caraway, tansy, fennel, and parsley have small, nectar-rich flowers and aromatic leaves.  These herbs attract lacewings, braconid wasps, aphid parasites, spiders, mealybug and spider mite destroyers, and minute pirate bugs, all of which prey on harmful insects.
The alkaloids in the tomato plant repels many insects, such as cabbage pests, asparagus beetles, flea-beetles and white-flies.  A very good companion with beans, cabbage, onions and peas.
The practitioner of organic gardening should try to use as part of their pest control strategy by employing companion planting.  Keep it in the back of your mind when planning out your garden, you can't go wrong.

You have companion planting in place and, yet, your garden still has a few unwanted guests.  Now is the time for bring out the heavy artillery, the trap.  Before you set up those traps, remember you want target the nuisance pests not the beneficial ones.

Sticky traps are quite effective in apprehending many types of harmful insects.  You can buy them or build them yourself.  One can build a simple yellow or white sticky trap by gluing either yellow or white strip of paper onto a piece of cardboard the same size and spray with adhesive.  Hang the traps from tree branches or place on a stake close to plants that are susceptible to pests.  Color determines the type of pests you will attract.  Yellow is the favorite of aphids, fruit flies, leafhoppers, leafminers, and whiteflies and white attracts flea-beetles, rose chafers or tarnished plant bugs.

In closing, I would like to mention my favorite garden assistants in pest control:  Ladybugs are the best garden insects because numerous garden pests fear their larvae and adult forms. They eat aphids, mites and other small insects in addition to the eggs of beetles and moths.  Praying mantises eat all sorts of bugs, the good ones and the bad ones.  They are not the best option; however, they do get the job done

Employing the principle of the above mention, ensures one of a chemically free food to eat which is nothing but GOOD.