Vegetables are an important source of proteins, vitamins and other essential nutrients. According to the U.S. Department of Agriculture, Americans spend between $165 and $345 on vegetables and groceries every month. We all know that vegetables are both seasonal and annual and that is what decides their rate in the retail market. But, there are vegetables that are sold at an ever-growing rate, because their production and harvesting involve a lot of human effort. This piece of information explores 6 such vegetables that are considered most expensive in the global market. Read to know the reason behind the expensive affair.