The Rostock University herbarium ROST was started from the private collection of Johannes A. C. Roeper, who was a botany professor and president of the university from 1836 to 1885. In his collection some parts from important collections from 19th century Europe and other continents have been preserved, including samples from famous researchers such as Heinrich G. Flörke (Roeper’s predecessor at the chair of botany), L. Adelbert von Chamisso, and Ferdinand J. H. von Mueller. However, already in 1886/87 the most valuable part of his collection—the herbarium of J. B. P. A. Monnet de Lamarck—was sold to the National Herbarium in Paris for 12,000 Francs, and the money was used at the time to finance the instrumentation of the new Botanical Institute and Garden. Roeper’s collection forms the basis of the large-sized general herbarium, and was ordered and revised over several years by his assistant, F. Oltmann (cf. Oltmanns, F., 1894: Das Rostocker Universitätsherbarium. Archiv des Vereins der Freunde der Naturgeschichte in Mecklenburg 47: 109–126).
Another important key aspect of the herbarium ROST is the remaining parts of the Krause collection, which is currently continued as the Mecklenburg Herbarium. The physician and botanist Ernst H. L. Krause (1859–1942) published numerous works including Flora von Rostock (1879, co-authored by C. Fisch), Mecklenburgische Flora (1893) and J. Sturm’s Flora von Deutschland (2 edition, 1900–1907). He was also involved in the taxonomy of many plant groups (Rubus and fungi in particular).
A considerable number of plant samples in the general herbarium comes from Roeper and P. E. Kühlewein. Incidentally, further notable contemporary botanists are among those that contributed to the collection: C. F. Schultz (Stargard), Franz W. Sieber, A. Braun, de Candolle, Wallich, Weihe, Boissier & Heldreich, W. Schimper, Bergius, Reichenbach, Treviranus, and Griesbach. Unfortunately, a number of lichen samples and types from the Flörke collection have been lost over the years.
In the Mecklenburg Herbarium, there are many samples collected by E. H. L. Krause himself, as well as the Griewank herbarium and samples from other lesser known collectors. Additionally, the Herbarium Vivum Florae Megapolitanae from G. G. Detharding (1816–1825) is present in this collection.
The Rostock University Herbarium contains around 85,000 samples from nearly 30,000 taxons, which are divided into the following groups: vascular plants (70,000), mosses (5000), algae (4500), lichens (3000), and a small sample of fungi.