Syringa vulgaris cultivars distribution to the groups according to the period of the flowering beginning under the conditions of the Southern Coast of the Crimea

Abstract

As a result of the analysis of long-term phenological observations, the cultivars of the lilac collection of the Nikita Botanical Gardens are divided into groups according to the timing of the beginning of flowering. It was revealed that in the conditions of the Southern coast of the Crimea the criterion for such distribution is the sum of effective temperatures of more than 5 ° C. For the early blooming cultivars (beginning of flowering, on the average, in the second- third decade of April), it ranges from 153 to 194 ° C, for cultivars blooming in the medium period (the third decade of April) - from 211 to 228 ° C, for cultivars that bloom into later varieties terms (the first decade of May) - from 247 to 283 ° C.