High Nutrient Concentrations of Hydroponic Solution Can Improve Growth and Nutrient Uptake of Spinach (Spinacia oleracea L.) Grown in Acidic Nutrient Solution

Hydroponic leafy green production offers high productivity and quality of crops but requires good management pH electrical conductivity (EC) to optimize the nutrient uptake. Nutrient solution is typically managed between 5.5 6.5, whereas lowering more acidic range (e.g., <5.0) can potentially mitigate problematic waterborne diseases. Plant response low species specific generally involves direct effect increased hydronium ions indirect effects pH-dependent factors, such as cations availability. To develop a new hydroponic strategy, ‘Corvair’ spinach plants were grown under 4.0, 4.5, 5.0, using deep-water culture system in growth chamber. Spinach shoot root mass after 19 20 days declined with pH. At lowest displayed stunted overall severely inhibited development. morphology at 4.5 or 5.0 normal small, suggesting that reduction these was likely result reduced tissue analyses showed decreased N, P, K, Mg, S, Cu, Fe, Mn, Zn concentration decreased. When strength three times improve availability, fresh weight concentrations (EC 3.4 dS·m −1 ) significantly improved still lower than those control (pH EC 1.4 ), respectively. analysis Ca, compared control. Under treatment all dry leaf similar higher control, except Mg Zn, which weak significance ( P < 0.06). This suggests additional optimization formula might further Together, our results will help low-cost methodology produce greens hydroponically.