In the 1600s and 1700s, Charleston, South Carolina, was an important port for the trading of rice, tobacco, and indigo. While most people could easily explain the first three products, most have no idea what indigo is, other than a dark blue color.
Indigo is a dark blue dye that can be made from the "peas" of certain tropical plants. Indigo was used to dye clothes blue. It was very valuable to plantation owners and farmers in South Carolina because it could grow on land that was not suited for tobacco or rice. Indigo would prove to be South Carolina's second most valuable crop. Some called it "blue gold." Over time, however, indigo production in South Carolina declined. After the Revolutionary War, English merchants started getting indigo from India. South Carolina farmers, however, weren't too sad. They soon turned their attention to growing a far more valuable crop --- cotton.