What was the Middle Colonies's economy based on?

The economy of the Middle Colonies was a diverse one. Fertile land and a decently long growing season meant that sufficient crops—such as wheat, oats, and barley—were grown to be exported to the other colonies. This is in contrast to the Southern Colonies (who mostly focused on the production of cash crops) and New England, which practiced subsistence-level farming.
In addition to farming, settlers in the backcountry of the Middle Colonies trapped animals (such as beaver and mink) for their pelts, which were a highly valued commodity for the fashion designers in Europe. A significant amount of timber and iron ore also came from this region.
Perhaps the biggest driver of the economy of the Middle Colonies was the role of its cities as commercial and shipping centers. Large port cities such as New York City, Philidelphia, and Baltimore became trading hubs. Goods from all over the colonies would find their way there for export to England. As these cities grew, more and more artisans and craftsmen took up their trade there, making them important centers of production.