The DRIS (Diagnosis and Recommendation Integrated System) and DOP (Deviation from Optimum Percentage) are applied to interpret the nutritional state of the peach tree (Prunus persica L. Batsch) at different times during its vegetative cycle. The DRIS which uses nutritional relations in the form of ratios, only established a correct order of the nutritional elements considered (N, P, K, Ca, and Mg) when the corresponding reference values and coefficients of variation the sampling season were used, and thus appears to be time dependant. The DRIS that uses nutritional relations in the form of products did not establish a correct order of limitations for the considered elements. The interpretations obtained by the DOP system coincided with the DRIS and also provide more valuable and extensive information that is easily applied and interpreted by computer.