Hello anttisepp!
I´m glad to see that there are other finns who is interested in palm growing.
Here on the Åland islands the climate for growing outdoors is the best in the country since we have the least fluctuations in avg.temperature (cooler summer and mild coastal winters), therefore i am giving palmgrowing a serious shot.

I am however a bit worried, since you on one hand have the warm summers that the palm requires to gather energy for the winter, on the other hand i know what the winters are like east of helsinki :-)

But i do wish you the weri best of luck in your growing!

Tyvärr kan jag ingen finska, så jag skriver på engelska istället (eller svenska helst)