The Saint Petersburg Botanical Garden, also known as the Botanic Gardens of the Komarov Botanical Institute or the Komarov Botanical Garden, is the oldest botanical garden in Russia, consisting of outdoor and rich indoor collections, which is situated on Aptekarsky Island in Saint Petersburg and belongs to the Komarov Botanical Institute of the Russian Academy of Sciences. It is 18.9 ha in area, and is bordered by Aptekarsky Prospekt (main entrance), Prof. Popov Street (second entrance), as well as the embankments of the river Karpovka and the river Bolshaya Nevka.
The garden was founded by Peter I in 1714 as a herb garden in order to grow medicinal plants and reestablished as a botanical institution under the name Imperial Botanical Garden in 1823. Ivan Lepyokhin was in charge of the botanical garden from 1774 until 1802. In 1930 it became subordinate to the Academy of Sciences of the Soviet Union and in 1931 was merged with the Botanical Museum into the Botanical Institute.
The garden has 25 greenhouses constructed in 1823-1824 (No. 1 – 28, the greenhouses No. 5 and No. 25 don't exist, the greenhouses No. 10-11 are shared), some of them are open to the public (guided visits only), including the huge collections of azaleas and other Ericaceae (No. 6), ferns (No. 15), cacti and other succulents (No. 16), various tropical plants (No. 18), the 23.5 m high Big Palm Greenhouse with an important collection of orchids (No. 26) and greenhouse with a pond featuring Victoria amazonica (no. 28). The night blossom of cactus Selenicereus grandiflorus, cultivated there since 1857, is a celebrated event announced in mass media and open to the public in the 16th greenhouse in June-July. The indoor collections suffered significant losses during the Siege of Leningrad in 1941-1944. Out of 6367 species only 861 survived.
The chain of greenhouses encircles the Southern Yard and the Northern Yard, the latter featuring an extensive outdoor collection of Iridaceae and bulb plants. The building of the botanical museum faces the Northern Yard in place of the non-existent greenhouse No. 5.
The outer park includes a small rock garden (constructed in the end of the 19th century) located in front of the Big Palm Greenhouse, and a 0.16 km² arboretum, organized partly as an English garden and partly as a formal garden. The park, unlike the greenhouses, is closed for visitors from October 1 to May 8. It is elevated only 1.5-3 m above sea-level and has thus regularly suffered from catastrophic floods characteristic of Saint Petersburg. The herbarium edifice built in 1913 stands in front of the main entrance.