A plantation is a large agricultural property dedicated to planting a few crops on a large scale. If you dream of having 3,000 acres to raise cucumbers on, then you have dreams of a cucumber plantation.
Plantation doesn't have to only mean massive single-product farms. A small grove of trees is also called a plantation, but usually when we use the word we mean the big farms. In the United States prior to the Civil War, crops like cotton and tobacco were grown on plantations in the South by exploiting the labor of enslaved people. In Latin America, many international companies own banana and coffee plantations.