Here are some suggestions for how to reduce the costs associated with purchasing nutrient-rich vegetables:
Since the price of vegetables varies depending on the area in which you live, we would suggest that you see which vegetables are less expensive in your local market, and then look in the World's Healthiest Foods book or website to check the nutritional value of those vegetables. If the vegetable(s) in question are not featured in the book or website, you can also look them up on the USDA National Nutrient Database for Standard Reference located at http://www.nal.usda.gov/fnic/foodcomp/search/, which is free and easy to use.
When vegetables are in season, they are usually less expensive and can also be counted on to taste better. This seasonal aspect of vegetables can be confusing, however, since most grocery stores are filled year-round with vegetables that are not truly seasonal.
That is why looking for local farmers' markets near your home is a great way to buy vegetables seasonally. Vegetables sold at these kinds of markets are very likely to have been grown within driving distance of your home. This usually guarantees that they are fresher, and because of the reduced transportation costs, they are usually less expensive. Many farmers' markets also have organic vegetables available. If you live in a more rural area and have access to transportation, you could also check to see if there are any local farms that have farm stands.
Finally, if you cannot find fresh vegetables that fit your budget, you should consider purchasing frozen vegetables. Frozen organic vegetables are getting easier and easier to find, and there are a surprising number of nutrients that stay fairly stable during the freezing process. While not as good as fresh vegetables, the frozen variety are far better from a nutritional standpoint than most people expect, and, particularly when organic, can make a very nourishing alternative.