A greenhouse study was conducted to determine the effects of foliar applications of magnetized, chelated liquid iron fertilizer for increasing the drought tolerance of two legumes. The study objectives were to determine the drought tolerance effects of four treatments on foliar gas exchange, soil moisture, and plant growth for soybean (Glycine max) and velvet bean (Mucuna pruriens) plants. The plant treatments included applications with chelated liquid iron fertilizer (2.5 and 5%) with a conventional boom sprayer, with and without magnets in the spray lines, and metal halide lamps. Three gas exchange measurements were collected before applying the foliage treatments and after two water stress treatments. A foliage and metal halide lamp treatment deactivated or unlinked nine interconnected gas exchange parameters that are correlated with plant defense activities during water stress conditions. The deactivation of interconnected regulatory gas exchange functions improved metabolic efficiency, reduced stress levels, and boosted plant resilience to abiotic stressors. Also, the study findings suggest that the study treatments maintained or increased the level of biologically structured water in plant tissues and vascular systems.