'Allgemeines teutsches Garten-Magazin oder gemeinnützige Beiträge für alle Theile des praktischen Gartenwesens' 1809, is online at Lower Saxony Heritage (Kulturerbe Niedersachsen) under the auspices of Gottingen State and University Library. The title roughly translates as: 'General German Garden Magazine or Useful Articles about all Disciplines of Practical Gardening'.
The magazine was issued regularly during the early part of the 19th century. It was one of the first periodicals to include coloured plates and advice on garden maintenance. It seems that these magazine issues were in fact compilations sourced from a variety of contemporary gardening and botanical-related accounts, pamphlets and (more obvious to me) botany books. At least a few of the illustrations are copied from, or modelled after, original sketches by the eminent British naturalist/illustrator, James Sowerby (eg.). So, this magazine compilation is more like the gardening Reader's Digest of its day, than a completely original publication. But perhaps that's a little unkind; it was ground breaking in its own way.
The written text dominates these 'general garden magazines'. Microfiche(?) or photocopy scans of the writing from the magazines can be seen here (compiled as yearly collections): this is within the Digital Garden Collection (newspapers, periodicals, company catalogues) of the German Horticultural Association, hosted by TU Berlin Universitätsbibliothek.