Research via questionnaires was conducted in 1998 among 400 farmers in the regions of central-eastern Poland. In each of the above-mentioned areas a hundred of questionnaires were carried out. Potatoes were produced on 314 farms, while sugar beets on 130 farms. The research embraced farms with varying production courses, excluding those with a high proportion of special production, e.g. herbs, hop, industrial fattening, and the farms of 10 hectars of agricultural farming lands. The aim of the research was to present the influence of certain factors on the yielding of potatoes and sugar beets on farms. Mineral fertilisation and the pesticides applied determined, to a greatest extent, the yielding of tuber crops. Greater yield crops were obtained on larger plantations and also on farms with a high proportion of tuber crops in the structure of arable crop land and specialising in the production of tubers and roots.