Anyways, before realizing that it is not mandatory, this was my idea, so please tell me what you think about it and could it work (and not kill the plant!).
It is around 20 degrees in our apartment, and it is less than zero outside. We don't have a single colder place in the apartment, but we do have old windows, that is - there is around 10cm between two window glasses.
My idea was to put the plant in there, and wrap it up a bit so it doesn't get much light. The temperature in between the windows is around 10 degrees.
Here are some pictures, please tell me what do you think, if this could work and is it safe!