No idea Johnny. I got mine as a tree. If you have lots of stones, could be worth popping some in a pot to see what happens.
It's not so much the cold that can damage the trees, but too much water in winter. In Tuscany many trees cope with snow in the winter, but the drainage is ok. I have my tree in a big pot (terracotta, of course) and have dug lots of grit into the soil (about 50/50 grit to compost - it's bloody heavy!) It's doing pretty well so far!