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Vertical farming stacks crop layers within climate-controlled buildings, using LED lighting tuned to specific wavelengths rather than relying on sunlight. Because water is recirculated in closed hydroponic or aeroponic loops, these facilities can use up to ninety-five percent less water than open-field agriculture growing the same crop. Proponents argue that locating farms inside or near cities shortens supply chains and reduces spoilage. However, the energy demand for artificial lighting and climate control remains substantial, and until that electricity comes from renewable sources, the carbon footprint of vertical farms may rival or exceed that of conventional greenhouses. Consequently, most commercial vertical farms currently focus on high-value, fast-growing crops like leafy greens and herbs, where the price premium offsets operating costs, rather than staple grains.