We examine the pore space evolution during saturated stage of soil drying as obtained via porosimetry. This is modeled at a microscale using Poiseuille flow through the capillary vessels of the size of the actual modal pores, with deformable walls driven bym evaporation flux at the external boundary. Onset of desaturation and the post-saturation stage are subsequently simulated as water cavitation mechanism and moving liquid/vapor interface inside the pores.