Several years of carpological research have deepened our knowledge of the plants grown during the early Middle Ages. In this paper, I shall confine myself to three questions (being fully aware that there are others): the choice of the species cultivated, the relation between evidence from remains found in excavations and written evidence, and the condition of the fields. The choice of the species was determined by three factors: the limitations of the soil itself, social and economic conditions, and cultural preferences. The comparison between the results of carpological studies and the written evidence produced some surprising results. The text of the Brevium Exempla, for instance, is not in agreement with the data from the excavations. The study of adventitious plants among the crops suggests the presence of low-nitrogen soils side by side with nitrogen-rich soils, even within the same field.