Abstract
Tomato (
Solanum lycopersicum
) production in southern Georgia contributes significantly to the agricultural economy but faces challenges from low-fertility soils and heavy reliance on chemical inputs. This study evaluated the effects of biochar application rates (0, 5, 10, 15, and 20 tons/acre) combined with conventional (granular and liquid) or poultry litter fertilizers on tomato growth, yield, fruit quality, and economic viability over two growing seasons (2023–24). Field trials were conducted on a Coastal Plain soil at the University of Georgia Tifton Campus, Hort Hill Farm, using a 5 × 2 factorial arrangement in a randomized complete block design (RCBD) with four replications. Results showed that poultry litter significantly improved plant height (+32%), stem diameter (+27%), and marketable yield (+39%) compared with conventional treatments. Biochar application had no significant effect on plant growth or yield but reduced fruit defects such as zippering by up to 47% at higher rates (15–20 tons/acre). Economic analysis revealed that combining poultry litter with biochar at 20 tons/acre achieved the highest profitability, with a cumulative benefit-cost ratio (BCR) of 2.08, while conventional treatments remained below the economic viability threshold (BCR <1). These findings suggest that integrating poultry litter with high biochar rates (15–20 tons/acre) can enhance soil health, improve crop resilience, and increase profitability in tomato production. This research provides actionable insights for growers in southern Georgia to optimize soil amendments, reduce reliance on synthetic fertilizers, and improve climate resilience in Coastal Plain soils.