Effect of Liquid Organic Fertiliser Produced from Organic and Fish Wastes on the Growth and Yield of Tomato

The use of inorganic fertilisers poses significant environmental and public health risks. This study evaluated the effects of liquid organic fertilisers (LOFs) produced from waste materials, including fish waste, molasses, wood ash, cow dung, goat manure, cow urine, poultry manure, rice bran, and nitrogen-rich plants, on the growth and yield of tomato plants. Four LOF formulations were prepared by combining fish waste with various plant materials (Gliricidia sepium, Sesbania grandiflora, Leucaena leucocephala, Tithonia diversifolia) and agricultural byproducts (goat manure, cow urine, poultry manure, rice bran). The experiment was conducted in a protected house using a completely randomised design (CRD) with five treatments evaluated: a control (Albert’s solution; T0) and four organic formulations (T1–T4) comprising fish waste, wood ash, molasses, and cow dung, each supplemented with different plant residues and organic amendments—Gliricidia sepium with goat manure (T1), Sesbania grandiflora with cow urine (T2), Leucaena leucocephala with poultry manure (T3), and Tithonia diversifolia with rice bran (T4) with each treatment having six replicates. Growth parameters recorded included plant height, number of leaves, number of branches, number of flowers, flowering time, dry weight, number of fruits, and total yield. Results showed that T0 (Albert’s solution) achieved the highest growth and yield. Among the LOFs, T1 (fish waste, wood ash, molasses, cow dung, Gliricidia sepium, and goat manure) demonstrated growth performance comparable to T0. However, fruit number and yield in T1 were significantly lower than T0. The highest average yield per plant was recorded in T0 (1796.8 g), followed by T1 (1246.3 g), representing approximately a 30% reduction compared to the control. These findings indicate the potential for developing LOFs that perform similarly to Albert’s solution using the raw materials in T1. Future research should focus on optimising the composition of T1-based LOFs to achieve yields closer to those of conventional fertilisers, thereby supporting sustainable tomato cultivation.