Drought conditions in the Southwestern U. S. and other parts of the world, the potential future impacts of climate change and politically-charged decisions regarding the allocation of water resources continue to challenge the agricultural community to find ways to successfully grow necessary food crops using less irrigation water. In addition, in many parts of the U. S., high levels of certain salts render ground water supplies unusable for salt-sensitive crops. Salt accumulation in soil and in tissues can also be a problem when water conservation methods are applied. Methods that save water and counteract salt accumulation are needed. Historically, magnetic water treatment (MWT) has shown promise in addressing both concerns though results have been inconsistent and somewhat controversial. This study evaluated the effect of MWT on lettuce yield, photosynthetic activity and nutrient levels under various irrigation reduction regimes. In addition, Watermark soil moisture sensors from Irrometer were used to measure the matric potential of root-depth soil of MWT, and non-MWT plants under those same regimes. Results indicated that statistically significant increases in yield, total chlorophyll and concentrations of some macro and micro-nutrients in plants treated by MWT could be achieved while using significantly less water compared to non-MWT irrigation water. In addition, MWT may also help counteract the effect of harmful sodium buildup in plants when less irrigation water was used.