Effect of Fertilization with the Sheep Manure Vermicompost on the Yield of Sweet Potato and Selected Properties of Soil Developed from Loess

The experiment was carried out in 2016–2018 in Łańcut, in the Rzeszów Foothills. The effect of fertilization using the sheep manure vermicompost on sweet potato of early cultivar (Carmen Rubin) and selected soil characteristics was investigated. The experiment was based on the method of randomized sub-blocks performed in four replications. Two cultivation technologies were used, in which the differentiating factor was fertilization applied or the lack of it. In the first technology (I nf – without fertilization), no fertilization was used in the years of research; in the second technology (II fv – fertilization with vermicompost), the vermicompost made from the sheep manure was applied. The vermicompost increased the yield of sweet potatoes of Carmen Rubin cv. and the share of large tubers in the yield structure. It also influenced the increase of organic carbon and total nitrogen in the soil as well as the content of available forms of phosphorus, potassium and magnesium. Some of the studied soil properties were less favorable compared to their condition before the start of the experiment.