Alkaline soils often present challenges, including nutrient availability and reduced microbial activity, which can adversely affect plant growth and yield. This study aimed to investigate the effects of different compost types and foliar applications of nanoparticle potassium on maize growth, quality and stress resistance under alkaline soil conditions. Conducted over two seasons (2023 and 2024), the research involved treatments of compost from banana trees and faba beans, along with foliar applications of nanoparticle potassium sources: silicate, citrate, and sulphate. Key parameters measured included growth metrics, chemical constituents, photosynthetic pigments, oxidative stress markers (proline and MDA), enzymatic antioxidants (CAT and POX), yield components, and quality traits. Maize treated with banana tree compost exhibited the highest growth metrics, including plant height, fresh weight, and dry weight. Nano potassium silicate led to superior growth compared to other potassium treatments. Significant increases in nitrogen (N), phosphorus (P), potassium (K), chlorophyll a, chlorophyll b and carotene levels were observed in plants treated with banana tree compost. Nano potassium silicate consistently recorded the highest leaf nutrients and photosynthetic pigment levels. Compost application reduced malondialdehyde (MDA) levels, indicating lower oxidative stress. The combination of banana tree compost and nano potassium silicate minimized stress markers while enhancing enzymatic antioxidant activity. The integration of banana tree compost with nanoparticle potassium significantly improved yield parameters, such as cob weight, grain yield, and quality traits, including protein and carbohydrate content. Finally, the findings demonstrate that combining banana tree compost with nanoparticle potassium can significantly improve maize growth, quality, and stress tolerance in alkaline soils. Future research should explore various compost types and their interactions with nanoparticle fertilizers, focusing on long-term impacts. Such studies will be vital for enhancing food security and promoting sustainable agricultural practices.