Coker embarked upon his career in the post-war economy with the stubborn conviction that the South's future hinged on the introduction of scientific principles to farming, coupled with the development of industry. At the cessation of armed hostilities in April 1865, the Coker family began rebuilding. Although Sherman's army had left no work stock, Coker had cotton seed and seed corn, which he planted with the use of an old
mule and a pair of
oxen borrowed from an uncle. He planted of cotton and of corn, which yielded 25 bales of cotton and 300 bushels of corn. At the prevailing prices, 25 bales of cotton brought $1,700, a small fortune in that time. Using those funds and others derived from mortgaging some of his land, Coker founded several businesses that were highly successful, including a cotton and naval trade post in Charleston, the Darlington Manufacturing Company, the Hartsville Cotton Mill, the Hartsville Oil Mill, and the Pedigreed Seed Company.
Hartsville, South Carolina, has enjoyed lasting benefits from his decision to build his own railroad spur (at his own expense) when other town merchants would not agree to help fund construction. In 1881, he organized and was elected president of Darlington National Bank, the only bank in the county. In 1890, Coker and his eldest son, James, began a search for a way to turn Southern pine trees into pulp for papermaking, and three years later, they had perfected a process. Shipping costs for the pulp made this business unprofitable, so Coker purchased his own papermaking equipment. That resulted in the formation of
Carolina Fiber Company. With precious few nearby customers for paper, in 1899, Coker organized the Southern Novelty Company, later renamed
Sonoco Products Company, to use some of the paper to produce cone-shaped yarn carriers. Today, Sonoco has over 19,900 employees in more than 335 operations in 33 countries, is a member of the Fortune 500 and the S&P400, and is South Carolina's largest corporation in terms of sales. ==Philanthropy and altruism==