Understanding the potential of clinoptilolite -CLI- for adsorption of NH4+ and K+, providing appropriate fertilizer formula, and evaluation of the produced zeolitic nutrient sources -ZNSs- to meet the plant need are the main objectives of this study. Three ZNSs -NH4+-saturated, K+-saturated and dual-purpose NH4+-K+ saturated CLI- were produced, assessed, and compared with commercial N and K fertilizers -CFs- on corn growth in a greenhouse. The results indicated that CLI can potentially adsorb both NH4+ and K+ to the maximum values of 25.00 mg-NH4+ g−1 and 47.61 mg-K g−1, respectively, and chemisorptions mainly followed the process of adsorption. Saturation of zeolite by NH4+ and K+ occurred after 10 and 15 d which lead to ZNSs with 2% and 5% of N and K, respectively. NH4+-K+ saturated CLI contained 1% N and 1% K. The greenhouse experiment showed no significant difference between ZNSs and CFs on plant growth. However, the application of both N and K in the form of zeolitic sources significantly increased the uptake of N by the plant. The highest uptake of K -2.05 g pot−1- occurred in plants supplied with both natural zeolite and CFs. The present results may benefit the future utilization of ZNSs in environmental friendly farming practices.

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