Seasonal development of the genus Heuchera L. plant varieties in the conditions of the Right-coast Forest-Steppe of Ukraine

Purpose. To study the seasonal cycle of development for introduced genus Heuchera L. plant varieties. Methods. Phenological, biometrical and analytical. Results. Based on the results of phenological observations, it was marked that the plants of Heuchera genus of the Right-coast Forest-Steppe of Ukraine pass through the all stages of seasonal development cycle. It was revealed that the phases of green shoots growing and blossoming are considerably prolonged. The phases of budding, blossoming and fruiting take place simultaneously. The studied plants, according to the nature of the development rhythm, are classified as a phenological “summer-winter green” type with winter dormancy, which determines the duration of their “decorativeness”.Conclusions. It was found out that the vegetation period for Heuchera species lasts 216–232 days. The beginning (I–II decade of May), duration (26–43 days) of the blosso­ming phase and phenological spectra analysis of the genus Heuchera varieties show that the rhythm of their development responds to the climatic conditions of the Right-coast Forest-Steppe of Ukraine. The decorativeness of introduced Heuchera varieties is evident from the budding to the end of the vegetation. So, they are able to provide a long decorative effect from March to early November according to different types of planting. As the fruiting phase is available, including the fruit-setting and viable seeds ripening, it is an absolute argument for selection work fulfillment.