The increasing social demands for scientific collections in botanical gardens, their display and practical use are the driving force for the development of both the collections themselves and various forms of their study. However, on the one hand now there is quite little research in the field of the functions of both the botanical gardens themselves and their collections. On the other hand, the educational function, as an integral feature of modern leisure in botanical gardens, uses the accumulated biological and ecological knowledge to transmit it to a wide audience. The paper presents the analysis of the significance of indoor and outdoor plant exposure for visitors to the Peter the Great Botanical Garden (St. Petersburg, Russia). The authors conclude about the importance of the public's request to the collections in order to increase their educational function. As examples, the overview of the greenhouse collection of plants, temporary exhibitions, outdoor collections and floral decoration is given. The analysis of individual collections of the Peter the Great Botanical Garden demonstrates their functional purpose, educational potential and current areas of exposure for further development. The authors describe the mutual influence of the educational function and the development of collections now. The paper presents the developed directions for the development of botanical collections and the conditions under which the educational function can be implemented.