Enhancing the wet structure of the root zone under drip irrigation is one of the objectives of the irrigation designers and researchers. Improved operating standards such as application rate enable us to realize the full potential of drip irrigation technology. In this study, we applied two approaches to improve the wetting pattern; an experimental approach and a simulation approach. For simulation, we used HYDRUS 2D/3D model to simulate the application of four discharge rates. We performed our experiments in an open field at Chlef, Algeria with tomatoes cultivated. The objectives of this research work were to validate HYDRUS 2D/3D model, and to evaluate the application rate effect on soil moisture distribution, root water uptake and crop yield of tomato plant. Based on the measured data, the infiltration process and root absorption caused by the applied irrigation water under different parameters were analyzed and simulated using the HYDRUS 2D/3D model. We found satisfactory agreement between the simulated and experimental approaches. These results demonstrate the reliability of HYDRUS 2D/3D in the simulation of volumetric water content values (VWC) compared to those measured in the field. Additionally, the results indicate that under a discharge of 3 L.h-1 with 3 days’ frequency gives uniform moisture in the profile of the root zone. This strategy was tested in a field experiment on tomato cultivation and has been shown to have a significant effect on root extraction and crop yield