Its Iowa, the bread basket to the world. The produce departments at any town with a grocery store will have more than enough choices in veggies. Not to mention the farmer markets with fresh produce. All the finer dinning establishments in the larger towns will have vegetarian items on there menu. For out on the route. Make yourself a snack bag. But again there will be fresh fruit smoothes, melons, sweet corn, bananas, grapes, and trail mix to name a few. You will have plenty to eat. Don’t worry about the food. Worry about getting training miles in. You will be riding 500 miles in one week. Back to back long days with hills. Not to mention triple digit heat index. Your comfort level is directly proportional to training.