List At year’s end, the University of Rostock Botanical Garden sends an updated list of the seeds collected from its cultivatied plants to over 500 gardens all over the world. The seeds are sent upon request [...] depending on the species (in some cases only a few days, in others, many decades) and its requirements for humidity and oxygen content of the environment, only about 1000 species of the 10,000 in the garden [...] are stored in a climate chamber. All seeds are then numbered and entered into the catalog. In the climate chamber, the seeds are kept at 4 °C for a maximum of 3 to 5 years, and are examined monthly to check
https://www.garten.uni-rostock.de/en/about-us/seed-exchange/