seed germination

[Komitee gegen den Vogelmord e.V.]

Hi all !
I`m new in the AEG. Till now I sowed my Arisaemas conventional without any
special handling. Before christmas I read in this list about the possibility of
faster germination through freezing the seeds.
What temperature is necessary and wich is to low ? Are tempereatures under -10 C
(14 F) dangerous ? And how long should the stay in the fridge ?
Alex, Germany
Zone 6 b