During a period of 5 years, we monthly monitor the phenology and the stem diameter increment of 12 of Schinus terebinthifolius trees. Dendrometer bands were used for it. This study was aimed to answer the following questions: (i) Are there conflicting demands for resource allocation in different phenophases? (ii) In which period does the stem diameter increment occur? (iii) Which phenophases are more likely related to stem radial growth? The phenological observations were carried out using the Activity Index. In order to identify patterns in phenology and diameter increment over the assessment period (2010-2015), we performed an analysis of seasonal decomposition, followed by Pearson’s correlation analysis. Apparently, there is no conflicting demand for resources, but an optimized distribution of them, regulated mainly by the allocation of nutrients derived from leaf senescence, as well as, temperature rise and photoperiod. Higher diameter growth rates occurred from December to March which coincided with the flowering period.