In many cases, conventional pest control options are more effective than organic ones and can be used less often to get the job done. For instance, the National Center for Food and Agriculture Policy
says that copper, when used as an organic fungicide, must be used at a rate of four pounds per acre. Sulfur must be used at a rate of 34 pounds per acre. Chemical fungicides, by contrast, can be used at a rate of 1.6 pounds per acre to generate the same result.
But in other cases, organic pesticides can be more effective than chemical ones. Biopesticides, which are made from living things or are found in nature, are often organic and carry lower risks while being more effective. Some biopesticides are targeted and work on only a small number of species. Others only affect the targeted organism for a short period of time and then break down quickly to reduce the risk of pollution. A few effective biopesticides that can be produced organically:
- Microbes. Fungus and bacteria can be used to control weeds and insects without having a negative effect on the environment.
- Plant materials. Garlic oil, black pepper and corn gluten all break down quickly after use.
- Hormones. Insect hormones, such as those that regulate mating behavior, can alter the way that a pest acts without killing it outright. For instance, a hormone that is used on moths may prevent them from mating or engaging in food-finding behaviors.
- Plant-incorporated protectants. These are genes and proteins that are introduced into plants through genetic engineering. These are rarely considered organic, as they fall under the umbrella of GMOs.
Biopesticides are often used as part of an integrated pest management approach that is more effective than using any one means of control alone.
Some organic options, such as companion planting, can be highly effective when used in conjunction with other methods. For instance, planting chrysanthemums in a bed with other plants can keep pests away from them in the garden. Other companion plants that may repel pests include rosemary, onion and thyme.