Inceptisols is among the predominant soil types in Indonesia; however, they are characterized by low fertility, which constrains their agricultural productivity. To address these limitations, this study aimed to assess the effects of organic amendments and K fertilization on the soil chemical properties and growth performance of stevia. A factorial randomized block design was employed, incorporating three types of compost: No Compost, Rice Straw Compost, and Leucaena Compost, combined with four levels of K₂O application (0, 75, 150, and 225 kg/ha). Soil parameters (pH, EC, CEC, and exchangeable K) and plant traits (height, biomass, and total soluble solids [TSS]) were assessed. Both compost types significantly improved soil chemical properties, with Leucaena compost yielding the highest pH and nutrient availability. Potassium fertilization significantly increased plant biomass, K uptake, and TSS content, particularly at 225 kg K₂O/ha. The combined application of organic and inorganic fertilizers yielded the most favorable outcomes for both soil health and stevia productivity. These findings underscore the complementary benefits of integrating organic and inorganic fertilization strategies to optimize stevia cultivation. This approach enhances soil health and nutrient availability, promotes sustainable agricultural practices, and contributes to addressing the national sugar supply gap by producing healthier natural sweeteners. Future research should investigate the long-term effects of these practices across diverse agroecological zones and evaluate the economic feasibility of their large-scale implementation.