Coordinating nutrient supply and flowering time for sustainable agriculture

The transition from vegetative to reproductive growth is a critical phase in the life cycle of a plant, directly affecting fecundity and overall crop productivity. This phase change is regulated by both endogenous genetic programs and environmental cues, including photoperiod, ambient temperature, abiotic stress, and nutrient availability. Among essential macronutrients, nitrogen (N), phosphorus (P), and potassium (K) support fundamental plant growth processes and actively regulate flowering time through distinct physiological and molecular mechanisms. Many studies have shown that both deficiency and excess of N, P, or K can either accelerate or delay flowering, depending on the species, developmental stage, and environmental context. In this review, we summarize the current knowledge on how N, P, and K affect flowering time in various plant species, including model and crop plants. We highlight the nutrient-responsive regulatory pathways and key genes involved in floral transition. By integrating recent findings in molecular genetics, physiology, and agronomy, we provide insights into how precise nutrient management can optimize flowering schedules, improve yield stability, and reduce fertilizer dependency. These insights, along with understanding macronutrient use efficiency, are essential for developing sustainable agricultural strategies that can adapt to changing environmental conditions, while ensuring food security and productivity.