Why did cotton become the main southern agricultural crop in the years before 1860

In the Upper South, the tobacco market was unstable. The prices constantly rose and fell drastically. It also exhausted the land on which it grew, which made it difficult for most growers to remain in business in the same place for very long. Making it at times a nonprofit-crop

However The growth of the textile industry in Britain and New England created a new demand for the crop. As a result, men and women moved into uncultivated lands to establish new cotton-growing regions