<p>The application of poultry litter in fields and excessive use of synthetic fertilizers in paddy wetlands are common in the State of Kerala. The study compared the effects of bio-amendments, like poultry litter and poultry litter-derived biochar (PLB), mineral fertilizers, and current farming practices that use fertilizers, lime, and cow dung on soil fertility, growth, and yield of rice plants. The research was conducted from November 2022 to March 2023 in the Vayalkkara East paddy field of Kunnukara village in Kerala State, India. Six treatments and controls were replicated three times and arranged in a complete randomized block design. A noticeable improvement was observed in the physicochemical properties of the soil under biochar treatments. The vegetative growth and rice yield were significantly higher for biochar treatments. Specifically, rice yield from treatment No. 4, where biochar was prepared at 300&#xa0;°C with a 60-minutes residence time (PLB300-60), reached 39.06 t/ha, which is six times higher than the control (6.4 t/ha), twice that of mineral fertilizer application (16.6 t/ha), and current farming practices (17.5 t/ha), and 1.5 times greater than feedstock poultry litter (24.4 t/ha). The study strongly recommends using biochar made from waste materials like poultry litter to enhance soil fertility, rice growth, and yield. This approach supports a circular bio-economy through sustainable waste management and good agricultural practices that protect the paddy wetlands and the surrounding ecosystem.</p> Graphical abstract