Influence of different iron liquid fertilizer doses and applications methods on broccoli (Brassica oleracea) growth and yield through controlled greenhouse environments

Abstract

This study aimed to evaluate the influence of different iron liquid fertilizer treats and applications methods on broccoli growth and yield. The results shows that lower concentrations of ferox (1 ml L^-1) applied by foliar and fertigation methods recorded significantly higher values of plant height, leaf count, chlorophyll content, stem diameter, and shoot weight relative to the control treatments. These positive differences in growth parameters translated into improved overall crop performance and increased yields when compared with the comparison groups. In contrast, increasing the concentration of ferox beyond 1 ml L^-1 demonstrated a noticeable decline in growth values, confirming poorer outcomes than the control in some cases and indicating possible toxicity effects at higher doses. This reduction was especially pronounced with the 2 ml L^-1 concentration, where foliar application produced significantly lower growth compared with both the control and the fertigation method. Therefore, the best comparative results were consistently obtained at 1 ml L^-1, which maximized productivity and enhanced yield, providing greater economic benefits relative to the control and other treatments. Conversely, excessive ferox concentrations caused nutrient imbalances and increased costs, showing negative differences when compared with comparison transactions. The controlled experiment at Bakrajo Technical Institute’s multi-span greenhouses during the 2024-2025 season under CRD design confirmed that precise fertilizer management is critical for optimizing broccoli growth, ensuring maximum efficiency, economic gains, and sustainable crop production.