The Cotton Belt spans the southern half of the Unites States, from Virginia to California. Cotton is grown in 17 states and is a major crop in 14. Its growing season of approximately 150 to 180 days is the longest of any annually planted crop in the country. Since there is much variation in climate and soil, production practices differ from region to region. In the western states, for example, nearly the entire crop is irrigated.
Planting begins in February in south Texas and as late as June in northern areas of the Cotton Belt. Land preparation actually starts in the fall, shortly after harvest. Stalks from the old crop are shredded to reduce food supplies for over-wintering pests. Usually, this residue is left on the surface to protect the soil from erosion. The use of heavy mechanical harvesters compacts the soil, sometimes requiring tillage to loosen the soil for the next crop’s roots.
Planting is accomplished with 6, 8, 10 or 12-row precision planters that place the seed at a uniform depth and interval. Young cotton seedlings emerge from the soil within a week or two after planting, depending on temperature and moisture conditions. Squares, or flower buds, form a month to six weeks later and creamy to dark yellow blossoms appear in another three weeks. Pollen from the flower’s stamen is carried to the stigma, thus pollinating the ovary. Over the next three days, the blossoms gradually turn pink and then dark red before falling off, leaving the tiny fertile ovary attached to the plant. It ripens and enlarges into a pod called a cotton boll.
Individual cells on the surface of seeds start to elongate the day the red flower falls off (abscission), reaching a final length of over one inch during the first month after abscission. The fibers thicken for the next month, forming a hollow cotton fiber inside the watery boll. Bolls open 50 to 70 days after bloom, letting air in to dry the white, clean fiber and fluff it for harvest.