Effect of Spring Fertilization on Early Blooming in Almond Trees: A Case Study from the Absheron Peninsula

Almond cultivation is highly vulnerable to early spring frosts, particularly in climates where warming trends and sudden cold snaps coincide with flowering. Among several agronomic factors influencing almond phenology, spring fertilization—especially nitrogen input—has emerged as a potentially critical determinant of bloom timing. This three-year study (2023–2025) conducted on the Absheron Peninsula investigates how foliar-applied nitrogen fertilizers affect the flowering onset of the early-blooming Guara cultivar of Prunus dulcis. Trees receiving nitrogen in early March bloomed 7–11 days earlier than untreated controls. In 2025, a striking early bloom was observed just 12 days after nitrogen application. However, this advancement coincided with frost events that caused 20–40% yield losses. These findings underscore the dual role of nitrogen as both a growth stimulant and a potential risk enhancer. In frost-prone regions, nitrogen fertilization should be carefully timed to avoid ecological and economic losses. This paper integrates field data, comparative analyses, and a comprehensive review of the physiological mechanisms linking nitrogen to bud development and bloom induction.