Vitality and Decorativeness of Plants of the Genus Spiraea L in the Arctic Zone of Russia (Коlа Peninsula)

Abstract

The article contains а hst of introduced specimens of the genus Spiraea L. in the Polar-Alpine Botanical Garden-Institute located abovethe Arctic Circle. The collection fund ofthe Polar-Alpine Botanical Garden-Institute contains 51 Spiraea specimens belonging to 12 species, 1 subspecies, 3 varieties, 4 cultivars and 2 hybrids. Most of the introduced accessions аге of seed origin. The age of the collection spireas is from 4 to 79 years. The article gives а comprehensive assessment of the viability and decorativeness of introduced plants of the genus Spiraea in the Kola Subarctic. Evaluated the degree of hgnification of the annual shoot, winter hardiness, retention of gmwth fonn, shoot-fonning ability, height gain, abihty to generative development, methods of reproduction in culture, crown architectonics, duration and abundance of flowering, color and size of flowers and inflorescences, attractiveness of fmits, color range of autumn leaf color, leafing duration, plant агата, damage, correlation between viability, decorative effect and the period of being in the experiment. Observations for 2000-2020 were used in the work. А verage score of winter hardiness of introduced S. betuhfoha, S. chamaedryfolia, S. nipponica, S. media 1-3. S. japonica, S. japonica 'Norroboth', S. х bumalda, S. х bumalda 'Shraederii', S. х cinerea 'Grefsheim', S. х rosalba аге frozen to the snow cover and soil level. Winter-hardy species retain their vital fonn, weak-hardy ones are аЫе to restore their growth foпn Most of the studied samples Ыооm and bear fmit not annually, reproduction is possiЫe with artificial sowing, using cuttings. The studied samples can Ье divided into groups: quite viaЫe and viaЫe high and medium decorative; less and less viaЬle high and medium decorative; non-viaЫe and absolutely non-viaЫe medium and low decorative. The most viaЫe and decorative under conditions of introduction to the Kola Peninsula are S. betuhfolia, S. chamaedryfoha, S. nipponica, S. media. S. japonica, S. japonica 'Norroboth', S. х bumalda, S. х bumalda 'Shraederii', S. х cinerea 'Grefsheim', S. х rosalba have low decorative qualities due to low viability.