Rezime:
The study targeted to assess major phenological and agronomic traits such as flowering and
fruit ripening time, as well as the yield and main characteristics of the fruit from three plum cultivars:
‘Valjevka’, ‘Kystendilska’ and ‘Stanley’. The research was conducted at the experimental plum plantation at the Research Institute of Mountain Stockbreeding and Agriculture in Troyan over 2019–
2022. This study aimed to compare the ‘Valjevka’ with the two cultivars mentioned above, which are
widely used in plum production in Bulgaria. Among the cultivars studied, ‘Valjevka’ showed the
earliest and ‘Kystendilska’ the latest flowering and ripening times. Cultivar ‘Stanley’ was characterized by the highest values of yield, fruit morphological and fruit chemical properties, while ‘Valjevka’
surpassed ‘Kystendilska’ in terms of the values of the mentioned properties. The variations in the
onset of the flowering phenophase were more pronounced between the individual experimental years
than between the cultivars. Additionally, the yield and morphometric characteristics of the fruit varied
significantly within the same cultivar, depending on the growing conditions of each experimental
year. Based on the obtained results, the cultivar ‘Valjevka’ can be recommended for commercial
growing in the Troyan region.