Growth, Yield, Quality and Economic Response of Irrigated Garlic to Integrated Nitrogen and Vermicompost

Abstract

A field trial was conducted in Mulo District, Ethiopia, during the 2024–2025 off-season to assess the effects of nitrogen and vermicompost on garlic growth, yield, quality, and economic performance. The experiment comprised a 4 × 4 factorial arrangement of four nitrogen rates (0, 50, 100, and 150 kg N ha⁻¹) and four vermicompost rates (0, 2.5, 5.0, and 7.5 t ha⁻¹) in a Randomized Complete Block Design with three replications. Data were analyzed using the GLM of SAS 9.4, and means were separated using Duncan’s Multiple Range Test at the 5% significance level. Nitrogen × vermicompost interaction significantly affected major growth, yield, and quality parameters (P ≤ 0.05). The combined application of 150 kg N ha⁻¹ and 7.5 t vermicompost ha⁻¹ produced highest plant height (80.4 cm), leaves per plant (13.6), leaf length (50.9 cm), leaf diameter (1.72 cm), bulb diameter (5.6 cm), average bulb weight (40.5 g), and bulb yield (11.8 t ha⁻¹), compared with 55.2 cm, 8.5 leaves plant⁻¹, 32.4 cm, 1.10 cm, 2.8 cm, 18.5 g, and 4.2 t ha⁻¹, respectively, in the control. The same treatment recorded the highest total soluble solids (41.3 °Brix), dry matter (32.0%), and storability (140 days), with the lowest moisture content (68.0%). Adjusted bulb yield increased from 3,780 to 10,620 kg ha⁻¹, generating a gross field benefit of ETB 531,000 ha⁻¹. Therefore, 150 kg N ha⁻¹ plus 7.5 t vermicompost ha⁻¹ performed best under irrigated conditions, similar experiments should be conducted across different seasons and locations.