Johannes Groenland (also spelled Grönland and called "Jean Groenland," 1824–1891) was a German botanist, horticulturist, and microscopist. He was born on 8 April 1824 in Altona, a borough of Hamburg that was part of the Duchy of Holstein at that time. He was the son of Johann Friedrich Grönland, a German organist and music teacher. Groenland was trained in pharmacology in his youth and served as a pharmacist in Altona, Hamburg, and Jena in his early 20s. In 1849 he joined the Schleswig-Holstein army to fight in the First Schleswig War. After the war, Groenland moved to Paris to work as an assistant to Louis de Vilmorin, a French biologist and horticulturist who was also a member of the family firm Vilmorin-Andrieux. While working for Vilmorin, Groenland worked with Theodor Rümpler to prepa