Eat local is a food mantra for a good reason—the longer your food is off the vine, tree, or stalk, the fewer nutrients it retains. Green vegetables lose about half their vitamin C within 24 hours of being picked, and they drop almost half of their heart-healthy flavonols. This means that even goodies from the farmers' market don't pack the biggest possible nutritional punch.
If you really want to eat local, grow veggies in your own backyard. Homegrown veggies are healthy, and they taste better, too.
If you're ready to venture into gardening, use rich soil for planting and rely on compost or organic fertilizers to address any deficiencies. What's in your soil is essential, because that's what you'll put in your body!