The paper will discuss urgent and topical problems that affect historical areas of urban open space. Its main goal will be the identification of phenomena which take place within it, and which mainly affect its natural tissue. The article will also contain such aspects as: an analysis of modern trends in revalorisation and the effects of its impact, an analysis of possible preventive measures that can be taken, as well as an evaluation of the influence of environmental factors on the condition of individual types of greenery.