Garden pests such as aphids, caterpillars and whiteflies can quickly destroy an entire plant or crop if uncontrolled. While many gardeners choose to use chemical pesticides, these can have side effects and are bad for the environment. Homemade organic pesticides can be just as effective and do not contain the harmful chemicals found in commercial products.
One of the most popular organic pesticides, a soap solution sprayed on plants gets rid of aphids, whiteflies, caterpillars, sowbugs, leafhoppers and grubs. Mix a few drops of cooking or olive oil with 2 tbsp. of dish soap in a gallon of water. Spray it over the plant, being sure to cover the undersides of the leaves.
Garlic will deter a wide variety of garden pests. Plant bulbs in gardening areas to help ward off unwanted pests, or create a garlic mixture to spray on the plants. Puree two garlic cloves in a blender or food processor. Add a 1 1/2 cups of water and puree the water with the garlic. Strain out the largest pieces of garlic. Mix the garlic puree with 1 gallon of water and spray on your plants.
Like garlic, peppers are very effective at ridding your garden of unwanted pests. Chop up the hottest peppers you can get, such as cayenne or serrano. Jalapeno peppers will also work if other varieties aren't available. Place the peppers in boiling water and then reduce the heat and allow them to simmer for about five minutes. Strain out the pieces of peppers, keeping the water, and spray your plants with the water after it has cooled.
Nicotine will kill many common garden pests. Make a nicotine brew by boiling water and then steeping unused chewing tobacco in the water. You can use a coffee filter tied up like a tea bag for the steeping, or place the chewing tobacco directly in the water and then strain it out after it is finished brewing. Spray the tobacco "tea" on the plants after it has cooled, making sure to spray the underside of the leaves. Do not use on any members of the bean family; it is fatal to these plants.
Alcohol will kill several types of undesirable insects. Products that contain alcohol are usually less expensive to use, although rubbing alcohol will also work. Add 1 cup of mouthwash that contains alcohol, such as Listerine, to 1 gallon of water. Mix well and spray on plants. This mixture works well on aphids and soft bugs.