Could be Adantium capillus-veneris, there's more than one Adiantum fern though. I have two, Adiantum venustum and Adiantum pedatum, both got through the very hard winter we had last, 7 weeks below freezing down to -17C.
They have different habits, yours looks to have the habit of Adantium capillus-veneris..
http://apalacheehills.com/Plan...
It's native to your country..
http://en.wikipedia.org/wiki/A...
