The best way to describe the economy of the Northern colonies during the time period you mention is to say that it was a mixed economy. This is in contrast to the Southern colonies where the economy was centered very much on the production of staple crops like tobacco.
In the Northern colonies, there were a large variety of economic activities. For example, on the coasts, there was a great deal of fishing and there was a strong emphasis on trade. Along with the trade came all sorts of industries that were centered on shipping -- there were shipmakers and sailmakers and coopers and all sorts of other industries that shipping needed. Farther inland, there were various types of agricultural activity that was needed to feed the coastal cities. These industries, along with many others, meant that the economy of these colonies was very mixed.