That's a wasteland, but probably not a desert. Per the link, it gets 569 mm of rain a year; dry, certainly compared to most of Germany, but most definitions of "desert" run around 250 mm/yr (consensus, but even if the cutoff is off by a little bit, it's over twice that). By comparison, Denver, which is arid but not a desert by anyone's imagination, is around 368 mm/yr.
I'm making this a separate reply because I just realized that this is one of those language confusion things. If Germans think a desert is a place without plants, regardless of water resources, they will wander out into places that Americans and Australians call deserts, which are insanely dry, thinking that of course there must be water somewhere. In the US and Aus, if someone says "that's a desert", you should be carrying 10+ liters per day per person and some extra if you get into trouble. Do not assume that you will find water anywhere.