Hi Sebastian,
this is not a font, but handwriting. This style is called Kurrentschrift, it was popular in Germany until the 1940s.
Your sample reads ‘Junger Fliegenschwamm’ [young fly agaric].

See these older threads for more information:
German script on "Das weiße Band" movie poster
Beautiful handwritten cookbook

There are not a lot digital Kurrent fonts. DS-Kurrent, the font mentioned in the first thread, will bring you only somewhat close. If you need something more commonly readable, try Viktor Solt-Bittner’s Voluta Script.
F

Hi Florian,

Great answer here. I found one freeware Kurrent style font. Wiegel Kurrent

http://www.chip.de/downloads/Wiegel-Kurrent-Font_36248849.html

not as great as Viktor or Voluta as you posted but it is free and might help to visualize the idea in the poster. I am going to try how that looks.

Thanks,
S

You’re welcome.
If it’s only (one line in) a poster, isn’t writing an option?

I tried Wiegel Kurrent...but does not work. It is almost certainly unreadable :(

Too bad.

Regarding writing...i am not that good at calligraphic work.