organic farming, the practice of raising plants—especially fruits and vegetables, but ornamentals as well—without the use of synthetic pesticides, herbicides, or fertilizers. In the United States, as elsewhere, awareness of the environmental damage and threats to health (see pollution; environmentalism) caused by DDT, dieldrin, and other insecticides and by the excessive use of chemical fertilizers has fostered interest in organic gardening, particularly among home gardeners. Organic gardeners use short-lived, biodegradable pest-killers or biological pest control and prefer manure for fertilizer. Organic farming on a large scale is both difficult and costly, but a small, steady market for organically grown, or "natural," foods supports a limited commercial effort in the United States. See also Integrated Pest Management; organic food.

or organic gardening

System of crop cultivation that uses biological methods of fertilization and pest control as substitutes for chemical fertilizers and pesticides, which are regarded by supporters of organic methods as harmful to health and the environment and unnecessary for successful cultivation. It was initiated as a conscious rejection of modern agri-chemical techniques in the 1930s by the British agronomist Sir Albert Howard. Miscellaneous organic materials, including animal manure, compost, grass turf, straw, and other crop residues, are applied to fields to improve both soil structure and moisture-holding capacity and to nourish soil life, which in turn nourishes plants. (Chemical fertilizers, by contrast, feed plants directly.) Biological pest control is achieved through preventive methods, including diversified farming, crop rotation, the planting of pest-deterrent species, and the use of integrated pest management techniques. Bioengineered strains are avoided. Since organic farming is time-consuming, organically grown produce tends to be expensive. Organic produce formerly accounted for a minuscule portion of total American farm output, but it has seen a huge proportional increase in sales in recent years.

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