Developmental patterning—such as longitudinal zonation of roots in growth domains, the transversal subdivision into layers of distinct cell types, and asymmetric growth during tropisms—is inherently multiscale and multiprocess. Consequently, computational models integrating these processes and scales are powerful tools to test whether our current understanding of involved players is both necessary and sufficient. Additionally, models help identify missing factors and reveal how the whole exceeds the sum of its parts. In this review, we discuss influential models that have advanced our understanding of root development and its adaptation to environmental conditions. We also highlight the potential for further integration of growth, mechanics, physiology, and physicochemical processes in these models. Such expansions are critical to advance the explanatory power of current models beyond genetic causes and identify the importance of cell size, nutrients, forces, pH, and ionic charge for developmental processes.