Hydroponics grows plants in nutrient-enriched water instead of soil. The system uses pipes or channels where roots directly absorb nutrients. It’s ideal for urban farming and regions with poor soil. With controlled light, pH, and nutrients, hydroponics achieves faster growth and 80–90% less water use. Example: Lettuce, basil, and strawberries are commonly grown hydroponically in vertical farms. Challenge: Initial setup costs and power requirements, but the returns and sustainability benefits are high.