Question

Why did Europeans use one-crop economies in their colonies?

Answer 1

So other colonies could trade them for their one crop , gets them more money you can say

Answer 2

In the time of the colonial era, European countries followed mercantilism. This helped the production of agricultural products which could be exported to their motherland as raw materials for industries production there. It also increased the importance of the capital market in the life of the colonial peoples. As a result, larger numbers of land was shifted from growing food crops to growing “cash crops,”.