Plant cultivation as an intermediate crop ensures the improvement of soil and water quality. Acquiring additional biomass from areas that remain without vegetation during the winter season allows for increasing its potential, which can be used for energy purposes. This work presents the results of physico-chemical properties analyses of six plant species grown as crops: beans (Vicia labia equina), field pea (Pisum sativum subsp. arvense), white mustard (Sinapis alba), serradella (Omithopus sativus Brot.), common agrinomy (Agrimonia eupatoria L), rye (Secale cereale). Plant material was obtained from experience conducted in laboratory conditions. Plants were grown in glass vases according to the root exudate recirculating system. The obtained biomass was subjected to the assessment of the content of basic and trace elements as well as the technical analysis of energy parameters. On the basis of the obtained research results, it was found that species of forecrop plants, irrespective of the method of cultivation, may constitute an additional source of biomass intended also for energy purposes. (C) 2019 Elsevier Ltd. All rights reserved.