The article for the fi rst time presents the comparative results of the content of ash substances, sulfur, phenolic compounds (tannins), ascorbic acid in the leaves of plants Iris hybrida, Hosta decorata, H. albomarginata, H. lancifolia, cultivated in the Central Siberian Botanical Garden (CSBS, Akademgorodok) and used in landscaping the urban environment of the Berdsk and Koltsovo settlements (Novosibirsk region) during the seasonal development in 2020.