It depends on how big their plantation was
In the south, slaves were used mainly for farming. The southern colonies' staple crop was rice. The middle colonies' staple crop was tobacco.
Slaves, and later sharecroppers, provided the labor to grow and prepare tobacco as a cash crop.
Many of the plantations that used slaves grew tobacco, a profitable crop back then.
Tobacco
The main crop of Virginia was tobacco. This was mainly grown in Jamestown and served as the main cash crop in the colony.
tobacco
They were maintained by tobacco and corn as the crop. Slaves were used in industries often.
It was mainly tobacco. They also grew corn and caught fish.
Sugar cane was the main crop. Tobacco was second.
The discovery of tobacco as cash crop in Virginia made the colonies labor supply grow. Indentured servants were first brought in to work the fields but soon after that slaves from Africa were used.
The establishment of tobacco farming in Virginia led to the importation of indentured servants and African slaves to work on the plantations. The demand for labor increased rapidly as tobacco became a profitable crop, prompting planters to turn to indentured servants and later to African slaves to meet their labor needs.
Well, actually the southern plantations grew only a single cash crop. Which was tobacco, then when the middle passage, and the slaves came to the south, tobacco was no longer the cash crop. It was cotton