The emergence of urban climate is a part of global climate change. It affects the early onset of spring phenological phases and exposes woods to late frosts. In the urban environment there is a more frequent occurrence of tropical days and hot waves. Thanks to the reaction of woody plants to the warmer climate of the sites, it is possible to predict the development of ecosystems in the current trend of increasing temperature and to implement measures for the maintenance of the health status of vegetation as well as the inhabitants of towns. In order to evaluate the differentiation of phenological phased of woody plants in the urban and rural environment, we monitored the onset of phenological phases of Acer pseudoplatanus L., Acer campestre L., Tilia cordata Mill., Fraxinus excelsior L., Corylus avellana L., Betula pendula Roth, Sambucus nigra L., Prunus spinosa L., Crataegus laevigata (Poir. DC), Larix decidua Mill. in the Liptov and Zvolen basins. We evaluated the occurrence of temperature extremes (frost and tropic days, hot waves) and their influence on the onset of phenological phases. In order to compare the stability of the onset of phenological phases, we have compiled long-term and short-term phenological calendars. In the results of the first objective, we disproved the hypothesis of the same average onset of phenological phases in the urban and rural environment. Due to the warmer urban climate, in the urban environment of both localities we observed earlier onset of spring phenological phases of most woods on average by 1-10 days. The influence of the altitude was manifested in Liptov basin through the biggest differences in the phenological phases. Most of the spring phenological phases started when the temperature limit reached 0 °C. Differences in the duration of the phenological phases were negligible between the environments except autumn phenological phases. In both locations, the most extreme year 2015, with the greatest occurrence of tropical days and hot waves, affected the earliest onset of yellowing and falling of leaves of most species, as well as the shortening of duration of yellowing, especially in the urban environment of Zvolen. The most sensitive reaction to the occurrence of both low and high extreme temperatures was achieved by Acer campestre and Corylus avellana. From phenological calendars, we found stability in the order of the onset of phenological phases. As a result of the temperature increase in the second half of February, during the period 2014-2017, the flowering of Corylus avellana in the Zvolen basin was shifted to winter.