The article presents the results of scientific research on four species of the genus Helianthus L. (H. annuus L.; H. tuberosus L.; H. mollis Lam.; H. debilis Nutt.). H. mollis and H. debilis species are new plants for the Republic of Moldova but valuable in terms of forage, honey and decoration. Biological features of growth and development, some phenological aspects are described, which demonstrate the adaptive potential of plants to the climatic conditions of the Republic of Moldova, with the perspective of acclimatization, introduction and valorisation in the conditions of the country.