Chamaecyparis obtusa IN PETER THE GREAT BOTANICAL GARDEN

Species of the genus Cypress trees ( Chamaecyparis Spach), family Cupressaceae - monoecious evergreen trees with a cone-shaped dense crown and aromatic resinous needles. In nature, they grow in East Asia (China, Japan, Taiwan) and North America; ornamental plants suitable for urban gardening and modern urban floristry. These plants look good in single, group and avenue plantings, especially in places with a suitable climate. They give valuable light, fine-grained, fragrant, hard and durable wood. The varietal wealth is so great - only 4 species have produced over 1500 modern cultivars. In culture, many varieties of Japanese selection are known, which have already proven themselves well in other countries. In most cases, cypress trees are suitable in areas with a maritime climate, mild winters and high humidity. Comparison with literature and archival data shows that in recent years and decades, against the background of climate warming, there has been a significant increase in the size of plants. Blunt cypress ( Chamaecyparis obtusa (Siebold et Zucc.) Endl.), in the Peter the Great Botanical Garden of V. L. Komarov Botanical Institute, Russian Academy of Sciences has been known since 1870, it grown in the collection in different periods -the first mention from 1870 to 1898, then in the period from 1949 to 1977. It has been included in the modern collection of the arboretum since 2009. At the age of 14, it is a double-trunked tree 1.94 m high, with a trunk of 0.20 m. In 2018, seed production was observed for the first time. In 2021, seed offspring were obtained. Given the ongoing warming of the climate in St. Petersburg and increasingly favorable wintering conditions, blunt cypress has prospects for wider cultivation in the North-West of Russia and introduction into the modern range of gardens and parks in St. Petersburg as a new ornamental plant. For planting blunt cypress, one should choose a place protected from cold winds, without stagnant moisture, near groundwater, but a slightly shaded place is possible. In the summer, plants should be watered, this is especially important for young plants, preventing their earthen coma from drying out. In winter, during heavy snowfalls, it is useful to shake off the plants to avoid snow breakage.