The economy in the Southern colonies was based on

Agriculture.

Explanation:

The economy in the Southern colonies was based on agriculture. Many Southerners relied on cash crops, plantations, and slave labor for their income.

The South had many plantations that would grow cash crops. Cash crops were crops that sold for a lot of money and were grown for profit. Southern cash crops during this time consisted of cotton, rice, indigo, and tobacco. In order to keep up with the amount of crops that were being grown, many Southerners relied on slave labor to tend to the fields.

After the Civil War, slavery got abolished and it was much harder for the South to continue their usual agricultural practices. The North heavily relied on industrialization during this time, making most of their money from factories, so they did not have to worry about the use of slave labor.