 The partly <unk> Middle Colonies enjoyed fertile soil vastly different from the nearby New England Colonies , which contained more rocky soil . Because of the large grain exports resulting from this soil , the colonies came to be known as the Bread <unk> Colonies . Pennsylvania became a leading exporter of wheat , corn , <unk> , hemp , and flax , making it the leading food producer in the colonies , and later states , between the years of 1725 and 1840 . Broad navigable rivers of relaxed current like the Susquehanna River , the Delaware River , and the Hudson River attracted diverse business . Fur trappers moved along these rivers , and there was enough flow to enable <unk> with water wheel power . 
