The project developed a fertilizer based on chitosan nanoparticles (a sugar derived from shrimp shells or fungi) to support crops during drought. Plants irrigated with nano- or bulk-chitosan solutions were grown under conditions of either sufficient water availability or drought. The results showed that chitosan nanoparticles at concentrations of 0.2 g/L and 0.4 g/L significantly improved growth, the number of healthy leaves, seedlings survival, and both dry and fresh biomass compared to water-irrigated groups. The bulk-chitosan solution (0.2 g/L) enhanced seedling growth. The findings indicate that chitosan irrigation can be an environmentally friendly method of protecting crops from water stress, which could enhance food production and availability in the most drought-affected regions.