the owner of this plant has his own website
Bananenzentrum Karlsruhe - Bananenzentrumand there you will find temperatures till -7°C (19.4°F) for this musa.
an other interesting site will be
Bananen, Anregungen u. Tips. with nice and impressing pictures (look for Impressionen >Bilder)
to translate some words use
dict.cc | Englisch-Wörterbuch | German Dictionary