Cauliflower Performance and Nitrogen Leaching Under Blends of Controlled Release and Conventional Urea

The efficiency of nitrogen fertilization in cauliflower depends on synchronizing nutrient availability with crop demand while minimizing environmental losses. This study evaluated cauliflower performance and nitrogen leaching under varying ratios of polymer‐coated controlled‐release urea (CRU) and conventional urea (CU). Two experiments were conducted in Florida using six CRU/CU proportions (0/100, 20/80, 40/60, 60/40, 80/20, and 100/0) at a fixed rate of 225 kg N ha −1 . Evaluated parameters included plant growth, biomass partitioning, yield components, tissue nitrogen dynamics, and nitrogen species in both leachate and soil. Results indicated that intermediate‐to‐high CRU proportions, particularly the 60/40 and 80/20 blends, significantly enhanced total biomass and root growth, improved commercial yield, and facilitated an earlier harvest compared to exclusive CU. Nitrogen accumulation followed a leaves > inflorescences > stems > roots hierarchy, with tissue concentrations declining over time due to biomass dilution. Environmentally, CRU‐predominant treatments effectively curbed early‐season nitrate and total nitrogen leaching. However, the exclusive use of CRU (100/0) occasionally left higher residual inorganic nitrogen in the soil postharvest, reflecting a release period that outlasted the crop cycle.