A photograph of a sweet potato plant, 1900.

Sweet potato cultivation spread to Europe in the fifteenth century as a result of the Columbian Exchange, but it had already spread to Polynesia, Hawaii, and other Pacific islands around the ninth century. In this photograph, one can see many features of the plant. The leaves and stem at the top of the plant would be above ground when the potato is growing, while the fibrous roots and storage roots at the bottom of the plant would be below the surface. The storage roots are the sweet potatoes that, during harvest season, require some heavy labor to dig out of the ground.