A Comparative Analysis of the Impact of Organic Comfrey Liquid Fertilizer and Inorganic Fertilizer on the Growth and Yield of Tomato (Solanum Lycopersicum)

The global shift toward sustainable agriculture has increased interest in organic fertilizers as alternatives to synthetic inputs, which are associated with soil degradation and environmental pollution. This study evaluated the effects of organic comfrey liquid fertilizer and inorganic fertilizer on the growth, yield, and economics of tomato (Solanum lycopersicum) The global shift toward sustainable agriculture has increased interest in organic fertilizers as alternatives to synthetic inputs, which are associated with soil degradation and environmental pollution. This study evaluated the effects of organic comfrey liquid fertilizer and inorganic fertilizer on the growth, yield, and economics of tomato (Solanum lycopersicum) production in Lusaka, Zambia. A randomized complete block design with three treatments control (no fertilizer), organic comfrey liquid fertilizer, and inorganic fertilizer was used. Data on plant height, leaf count, and fruit yield were collected and analyzed using ANOVA and LSD post-hoc tests. Results showed significant differences among treatments in final fruit yield (F(2,24) = 23.548, p < 0.001). Organic comfrey fertilizer produced the highest mean yield (186.67 g/plant), followed by inorganic fertilizer (128.56 g/plant), and control (75.67 g/plant). Post-hoc comparisons confirmed all treatment means differed significantly (p ≤ 0.001). Organic fertilizer also promoted greater plant height and leaf count, particularly at later growth stages. Cost-benefit analysis indicated that comfrey fertilizer offered a sustainable and economically viable alternative to inorganic inputs. These findings support the use of comfrey liquid fertilizer as an effective organic amendment for enhancing tomato productivity while supporting soil health and environmental sustainability.