There are four areas to consider related to control of garden pests. Prevention Pest Management Weed Management Disease Management Though related, these areas need their own attention and procedures for control. This book focuses on Pest Management. Organic gardening relies primarily on biological and cultural practices to manage pests, weeds, and diseases, but thinking that organic gardening means vegetables free of any chemical pesticides is not quite right. Organic pesticides are derived from naturally occurring substances. They need to be extracted, processed or concentrated from the natural source, but they are generally not chemically changed. In contrast, "synthetic" pesticides are usually derived from petroleum sources and the chemistry of the molecules is changed to give a desired product. Why are organic pesticides preferred by some gardeners? They breakdown rapidly in the environment after application, they act to prevent further insect feeding and many have a low toxicity to people and animals. Organic gardeners can use certain pesticides -- chemicals that are derived from botanical and mineral-bearing sources. These chemicals break down more rapidly than common synthetic chemicals. Long term natural pest control is the most cost effective approach to managing insect pests. This method provides stable, continuous suppression of pests by promoting their natural enemies. The long term approach is also the least toxic method of controlling insects. Chemicals are normally not needed and should be used only as a last resort. Pesticides Permitted in Organic Gardening As a general rule, most pesticides are prohibited for organic production. The use of botanical and mineral-bearing pesticides can also be incorporated into an Integrated Pest Management (IPM) approach to growing crops. IPM relies on a variety of pest control means rather than on one product or method. The pesticides discussed in this book are appropriate to include in IPM programs. Organic pesticides fall into five broad groups: Botanical Microbial Mineral Household Remedies Plant Barriers and Insect Traps Botanical pesticides are obtained from the roots, leaves, seeds, stems or flowers of plants. Many plants manufacture chemical compounds that protect them from pest attack. Once identified, people began using these chemicals to protect valued plants against similar pests. Microbial pesticides contain pathogenic bacteria, viruses, fungi or nematodes. These microorganisms serve as natural enemies to some insects and control natural population outbreaks under certain conditions. Manufacturing processes have allowed the application of these microbial pesticides in the form of sprays, dusts, baits or granules to control pest outbreaks. Mineral-based pesticides are derived from inorganic chemicals. They are crystalline, stable chemicals that do not evaporate but generally dissolve easily in water. Household remedies center around repurposing various detergents and chemicals used around the house for pest control. Plant barriers, companion planting and insect traps constitute the fifth tool for organic gardening and control of pests.