Organic farmers who grow their crops in soil participate in a protest in Stowe, Vt., in 2015. Critics say the organic label is at essence about the health of soil, and did not want to allow crops raised in hydroponic systems to be labeled organic. Their efforts to strip hydroponic vegetables of the organic label failed this week. Wilson Ring/AP Images hide caption

Baby basil is planted in PVC piping through which nutrient-infused water flows at regular intervals at a hydroponics farm in Nevada. This week, the National Organic Standards Board is set to vote on whether foods grown hydroponically can be sold as "certified organic." Julie Jacobson/AP hide caption

These Central Valley sheep are happily munching on sprouted barley grown indoors. Farmer Mario Daccarett says the barley, grown in shipping containers, is sweet and keeps his sheep full longer. Ezra David Romero/Valley Public Radio hide caption

Hydroponic tomatoes are now just as tasty as tomatoes grown outside in perfect summer conditions, scientists say. iStockphoto hide caption

At the Mini-Farmery in North Carolina, greens grow on the walls and customers can pick their own produce. Amy Edwards/New Image Studio hide caption