Understanding vegetation dynamics in ecologically fragile regions is crucial for assessing the impacts of climate change. This study employed the kernel Normalized Difference Vegetation Index (kNDVI) to characterize the vegetation changes on the Loess Plateau from 2001 to 2022, analyzing its spatiotemporal trends, stability, and persistence, and quantitatively evaluating the environmental driving factors using the Geodetector method. The results showed a significant increasing trend in kNDVI, reflecting an improvement in vegetation coverage. The coefficient of variation (0.03–4.41) revealed significant spatial heterogeneity and low vegetation stability, while the Hurst exponent (0.21–0.77, with an average of 0.67) indicated strong persistence in vegetation changes. Climatic factors, especially the mean annual precipitation (MAP) and the aridity index, were the dominant drivers of kNDVI changes. There were significant interactions between climatic factors and biophysical and anthropogenic factors, particularly the interaction between MAP and vegetation type, topography, and land use change, which explained over 60% of the variation. These findings deepen the understanding of nonlinear vegetation-environment interactions and provide key insights for optimizing ecological policies on the Loess Plateau.