Dear woofie, after minus 10f they will start to loose their fronds. Mine have been down to minus 26F; but they are protected by a "microclimate" I have made with the fence, the shed and the warmth of the house. Plus next doors house. Of course they can take a bit of looking after in the summer as they do like to be kept moist! I just spray them with the hosepipe and they are fine.
They seem to like it here and have been moved about a lot in the past. I do not put mine in a greenhouse, but a lot of people do. If you have a greenhouse use it.
The biggest one is 35 years old, although i do have smaller ones. All were grown from spores.
Regards.
Neil.
A link:
http://www.forestferns.co.uk/t...
This is now a renamed plant!
