Phenological Stages of the Species Jacaranda mimosifolia D. Don. According to the Extended BBCH Scale

The jacaranda (Jacaranda mimosifolia D. Don.) is a widely cultivated ornamental tree species in urban landscapes, but recent research has highlighted its additional ecological and industrial potential. However, no detailed phenological description has been available for this species. The objective of this study was to establish a standardized phenological scale for Jacaranda mimosifolia D. Don. based on the BBCH coding system and to determine the thermal requirements (growing degree-days, GDD). Thirty-nine secondary stages were used to describe the life cycle of jacaranda in this BBCH scale, distributed across seven principal growth stages (PGSs). Of these thirty-nine secondary stages, five stages correspond to dormancy and sprouting (PGS-0), six stages correspond to leaf development (PGS-1), three correspond to the emergence of the flowering organ (PGS-5), eight correspond to flowering (PGS-6), ten correspond to fruit formation (PGS-7), three correspond to ripening fruit (PGS-8), and four correspond to the beginning of dormancy (PGS-9). Thermal integral analysis indicated that jacaranda requires approximately 3800 accumulated degree-days (GDD) to progress from dormancy to leaf fall. This phenological framework enhances understanding of the growth cycle of Jacaranda mimosifolia D. Don. and provides a useful reference for improving the timing and efficiency of management and phytosanitary treatments in Mediterranean conditions.