This study was conducted to determine the effects of temperature on nutrient release patterns of three polymer-coated fertilizers (PCFs), each using a different coating technology: Osmocote Plus 15N-3.93P-9.96K, Polyon 18N-2.62P-9.96K, and Nutricote 18N-2.62P-6.64K. Each fertilizer was placed in a sand-filled column and leached with distilled water at ≈100 mL·h-1, while being subjected to a simulated diurnal container temperature change from 20 to 40 °C and back to 20 °C over a period of 20 hours. Column leachate was collected hourly and measured for soluble salts and NO3-N and NH4-N content. For all fertilizers, nutrient release increased and decreased with the respective increase and decrease in temperature. Nutrient release patterns of the three fertilizers differed, with Osmocote Plus showing the greatest overall change in nutrient release between 20 and 40 °C, and Nutricote the least.