The experiments aiming to describe the conditions determining cracking of lupine pods and seed shedding showed that their physical properties were the main factor responsible for the process. It results from the anatomical structure of the fruits. In this paper we were looking for the correlation between seed shading the field conditions and the physical features of pods. We examined the resistance of raphs, sclerenhyma layer thickness and selected morphological features (form factor). The experiments were conducted on blue lupine varieties that has the most susceptible for cracking.