The Effects of Organic Liquid Fertilizer (Vegetable Waste) on Moisture Retention, Soil Physical Properties and Yield of Lettuce (Lactuca Sativa L.) Grown in the Malkerns Area, a Region in the Kingdom of Eswatini.

Abstract

The main aim of this study was to investigate the effect of organic food waste on the condition of soil and the yield of vegetables. The experiment was a randomized block design with N:P:K at ratio of 2:3:2(37) inorganic fertilizer, organic fertilizer (vegetable food waste) and no fertilizer as the three treatments using no fertilizer as a control. There were three replications per treatment. The vegetable food waste was processed in a closed container along with addition of stillage and sugar in anaerobic conditions for 3 weeks. The vegetable food waste liquid fertilizer was analysed and the NPK values were found to be 0.83 %, 16.5 mg/kg, 20.62 cmol/kg, respectively. After application of treatments in the soil, the results of the study showed that vegetable waste had the highest yield per head (355.5 g) followed by synthetic fertilizer and no fertilizer treatment (control) with 283.2 g, and 253.1 g, respectively. Similarly, vegetable food waste had the higher moisture holding capacity of 0.237 cm 3 /cm 3 while synthetic fertilizer and the control both were 0.139 cm 3 /cm 3 . The results obtained from the study showed that liquid vegetable food waste fertilizer can be used as an alternative to synthetic fertilizer to increase crop yield and improve soil physical properties while reducing the negative impact of synthetic fertilizers on the environment as well as the environmental effect of disposing vegetable food waste in landfills.