Barley and corn seedling were used to investigate the influence of zeolite and phosphogypsum on a) growth, photochemical activity of chloroplasts and chlorophyll content; b) content of water soluble Sr, Ca and Cd in the soil, and c) uptake of these elements in relation to photosynthetic activity, and content of these elements in the soil. Phosphogypsum was found to negatively influence the growth and development of the seedlings, affecting their morphological traits, biomass production and photosynthetic activity. Therefore, application of phosphogypsum combined with natural zeolite enabled a complete removal of the “side effects”; of phosphogypsum treatment. Furthermore, the application of zeolite was found to increase photosynthetic activity and biological yields of barley and corn plants. The results of our investigation showed the absence of close correlation between the content of water soluble Sr in the soil and its accumulation in plants. However, the uptake of Sr by barley plants was found to be highly dependent on their photosynthetic activity and leaf area.