Comparative Evaluation of the Biological, Chemical Properties, and Nutrient Content of Tithonia diversifolia and Cassava Peel Composts as Sustainable Soil Amendments

The increasing demand for sustainable agricultural practices necessitates exploration of organic waste materials as effective soil amendments. This study evaluated microbial activity, chemical properties, and nutrient content of compost derived from cassava peels and Tithonia diversifolia in a 1:3 ratio by dry weight, each mixed with poultry manure under controlled conditions. Throughout composting process, parameters such as temperature, pH, carbon dioxide (CO2) levels, microbial activity, and nutrient content were evaluated. Nutrient contents were determined according to standard procedures and data were analyzed using analysis of variance (ANOVA) at α=0.05. Results showed that cassava peel compost (CPC) maintaining higher bacterial counts, peaking at Week 6 (11 x 10⁷ cfu/ml), while Tithonia Compost (TC) peaked earlier at Week 4 (7.2 x 10⁷ cfu/ml). Fungal counts were consistently higher in CPC. Moisture content decreased over time, with CPC retaining slightly more moisture than TC. Temperature trends revealed higher initial temperatures and microbial activity in CPC, peaking at 62.2°C, while TC peaked at 57.6°C. CPC exhibited a mildly acidic pH (6.67) that gradually increased to neutral/slightly alkaline levels by end of composting, while TC was consistently alkaline, stabilizing at 8.37. TC exhibited higher nutrient content, attributed to its rich organic matter and lower C/N ratio, which expedited microbial decomposition and high nutrient release. However, CPC had a higher C/N ratio and fungal activity resulting in gradual nutrient release. Complementary use of TC and CPC on field trials is recommended to assess their long-term effects on soil health and crop yield under different agronomic conditions.