Physically preventing bugs from touching your plants

One of the best methods to prevent insect damage is physically preventing bugs from touching plants. Several methods work well depending on the plant and the insect. All methods mentioned are very effective and reasonably inexpensive when done properly.
Row covers are sheets of spun-bonded polypropylene that can be draped over food crops to eliminate insect problems. They are lightweight enough to drop directly onto most crops, or you can create a frame for the covering by bending PVC pipe or bamboo sticks. (Cheap tip: You can even grow useful bamboo stakes yourself.) The fabric stands between the bug and its meal. It allows most available sunlight and water to pass through freely and protects from wind, hail, slight frost, and windborne weed seeds, as well as bugs, birds, and small animals.

It is critical to cover the crops early, before bugs get to them, which is when planting or transplanting them. A sprinkling of inexpensive diazinon or diatomaceous earth raked into the soil will kill any current soil-dwelling inhabitants. This is important for direct seeded melons, a special favorite of cutworms. Leave enough slack in the fabric to allow for the eventual growth of the plants, and anchor the fabric along the edges with dirt or planks. This is very important, because not only might it blow away but also the idea is to prevent bugs from getting to the plant, and they crawl through the smallest spaces. Lift the cover occasionally to monitor a plant's progress.

Covers are most convenient for plants that will not flower for harvest, such as carrots or broccoli. Covers will work for plants that flower, such as cucumbers, as long as you remove the covers in time for pollination to occur.

Treat these fabric covers with respect to get your money's worth. Work cautiously around them, a careless swing of the hoe will tear the fabric. Never walk on them, always go around. Don't drive stakes through them as anchors. Fabric anchored by stakes will not always keep out bugs anyway, and the stakes will cause rips. Cut the fabric down to a size you can handle easily. You will run less risk of damaging the fabric while you are working with it. Above all else, fold or roll up fabric covers at the end of the season and store them. Don't just drop them in a pile on the floor of the garden shed, since mice find them irresistible for winter housing.
and organic protection, use a stem collar. Stiff paper or cardboard are often recommended, but one of the best and cheapest substitutes I have found is a plastic drinking straw. Salvage used straws, and cut them into 1 1/2-inch long pieces. Slit the pieces up one side, pull the plastic apart and fit around the stem of each transplant. Push the plastic down into the soil, and you have a plastic barrier no cutworm can chomp or climb.

Stem collars protect tender transplants from cutworm damage. Cutworms are underground caterpillar-like bugs. They will devastate beans, broccoli, cantaloupe, and a vast array of other plants with equal zeal. They are especially prevalent in new gardens freshly dug from sod or areas filled with weeds. A dash of diazinon or diatomaceous earth will eliminate those present at application. But for continuing