Chemical potassium fertilizers used to increase plant yield; nevertheless, overuse of these fertilizers is costly and pollutes the environment. So, many farmers have turned to cheaper alternative sources of potassium, such as foliar spraying potassium silicate or natural substitutes like feldspar with high potassium content. In this context, two field experiments through the two following seasons of 2022/2023 and 2023/2024 were carried out in a private farm on reclaimed sandy soils in EL-Minia City's western district, El-Minia Governorate, Egypt, to study the effect of different potassium sources (without addition, potassium sulfate, feldspar, and potassium silicate) with or without inoculation by Enterobacter cloacae (E. cloacae) were arranged in a split plot design with three replicates on vegetative growth, yield, and tuberous roots quality of cassava plants "cv. American" as well as soil remaining nutrients. The soil fertilized with potassium sulfate or feldspar, either alone or in combination with bacteria enhanced vegetative growth parameters compared to those of un-fertilized soil. But feldspar exhibited a positive effect on remaining nutrients in soil, tuberous roots yield, and quality of tuberous root, i.e., starch, total carbohydrate, and total soluble sugar content. Moreover, the inoculation with E. cloacae significantly increase in all vegetative growth parameters, yield, and tuberous root quality of cassava; therefore, our findings suggest that the application of feldspar mineral combined with E. cloacae could be considered as an alternative for chemical potassium fertilizers for cassava production in reclaimed sandy soils.