The German viticulture expert Johann Christian Metzger (1789-1852) was after a gardener apprenticeship in Karlsruhe senior assistant in the castle garden of Schwetzingen and senior gardener with the Margrave Ludwig in Karlsruhe, and then the function of a plantation inspector for the Enz, Kinzig, Murg and Pfinzkreis based in Rastatt. In 1812, Metzger was appointed gardener in charge of gardeners at the Heidelberg Castle and appointed garden director in 1843. In addition to other functions, he was a member of the Baden Landtag, a member of the University of Heidelberg and president of the orchard section for the gatherings of German wine and orchard producers.
He dealt with numerous fruit and wine-growing topics, but also with tobacco growing. Metzger was also a member of numerous scientific and professional societies. He published the works "The Rhenish Viticulture" and in 1836 together with Lambert Joseph Leopold Freiherr von Babo (1790-1862) "The wine and table grapes of the German vineyards and gardens". He did that in the ampelography an important contribution to the determination of grape varieties. See also below Viticulture personalities,