Strategic Enhancements in Onion Cultivation Through Evaluating Plant Density and Harvest Intervals for Superior Yield and Profitability

The experiment was conducted at the agricultural research farm of the Department of Agronomy and Agricultural Extension, University of Rajshahi, Bangladesh from December 2020 to April 2021. The aim was to investigate the impact of plant density per hill and harvesting time on the growth, yield, and economic benefits of onions. Three plant densities were tested: one plant per hill (P1), two plants per hill (P2), and three plants per hill (P3). Additionally, two harvesting times were evaluated: 110 days after transplanting (H1) and 125 days after transplanting (H2). The experiment followed a Randomized Completely Block Design (RCBD) with three replications. Both plant density and harvesting time significantly influenced most growth and yield parameters. The highest values for leaf diameter, neck diameter, bulb length, bulb diameter, fresh bulb weight, dry bulb weight, and yields per hectare were observed with two plants per hill (P2). Similarly, the highest values for those parameters were found with the later harvest time of 125 days (H2). The combination of two plants per hill and harvesting at 125 days (P2H2) produced the best results, including the highest leaf and neck diameters, bulb dimensions, fresh and dry bulb weights, and yields per hectare. This combination also achieved the highest Benefit-Cost Ratio (BCR) of 2.12, compared to 1.71 for the one plant per hill and 110-day harvest combination (P1H1). Therefore, the study concludes that planting two onions per hill and harvesting at 125 days after transplanting yield the best growth, yield, and economic benefits.