<p>This study examines the practical application of MicroChar to enhance phosphorus availability in nutrient-deficient soils. The char was enriched with organic nutrients and inoculated with a mixed microbial culture of bacteria and fungal spores. Combining incubation trials with two soils and pot experiments amending Regosol soil with 2% MicroChar, we examined impacts under optimal soil water and drought conditions, using pea (<i>Pisum sativum</i> L) as an indicator crop. While initially increasing soluble phosphorus concentrations in soil pore water, MicroChar application led to sustained enhancements in phosphorus availability throughout incubations and pot experiments, benefiting plant growth under optimal conditions. Under optimal water conditions, MicroChar also stimulated pea root, shoot, and pod growth, implying enhanced phosphorus nutrition. However, drought stress suppressed plant response regardless of phosphorus availability. Overall, MicroChar augmented plant-accessible phosphorus in phosphorus-deficient Regosol, bearing critical implications for sustainable phosphorus management in agriculture. Strategic MicroChar application shows potential to improve phosphorus efficiency. Further trials across diverse soils and climates would extend these findings.</p>