Response of Garlic (Allium sativum L.) Growth and Bulb Yield to Application of Vermicompost and Mineral Nitrogen Fertilizers in Haramaya District, Eastern Ethiopia

Yield of garlic is often constrained by low and unbalanced nutrient supply in the soil. Thisstudy was conducted to assess the effect of application of vermicompost (VC) and mineral nitrogen (N)fertilizer on growth and bulb yield of a garlic variety named ‘Chelenko I’ The experiment was conductedduring the 2016 main rainy season. The experiment was laid out as a randomized block designed in afactorial arrangement and replicated three times per treatment. The treatments consisted of four rates ofvermicompost (VC) (0, 2.5, 5.0 and 7.5 t ha-1), and five rates of mineral nitrogen (N) fertilizer (0, 52.5, 80,105 and 130 kg N ha-1. Data were collected on days to maturity, plant height, leaf number, yieldcomponents, namely, bulb length and clove weight, and marketable and unmarketable bulb yield of garlic. The data were analyzed and computed using SAS software version 9.0 and the means were separated byusing Turkey’s Test at 0.05 probably level . The results revealed significant (P < 0.05) differences in earlymaturity (130.48 days) at control treatment (zero fertilizers) while late maturity (135.50 days) was atapplication of 7.5 t ha-1 of VC. Significantly (P < 0.05) maximum plant height (60.65 cm), clove weight(2.71 g/clove), and marketable bulb yield (12.32 t ha-1) were recorded at the rate of 7.5 t ha-1 of VC. Dueto combined application of VC (7.5 t ha-1) and mineral N fertilizer (130 kg ha-1) unmarketable bulb yieldwas reduced by 41.03% over the control treatment. The highest net benefit was recorded from themaximum marketable bulb yield of garlic at the application of 7.5 t ha-1 of VC and 130 kg N ha-1 . Thus, itis concluded that combined application of vermicompost and mineral nitrogen fertilizer resulted inoptimum production of the crop in the study area