The publication presents historical outline of the development of investigations of physical properties of plant material in the Dobrzanski's Institute of Agrophysics PAS in Lublin. Major directions and range of the investigations of cereals, leguminous, rapeseed, fruits and vegetables are presented considering their geometrical features, mechanical and optical properties as well as basic physical characteristics. A special stress was paid on a considerable range of changeability of the properties according to various factors like: soil conditions, varietal features, agro technique, maturity and moisture content of the studied material.