In article ,
Janet wrote:

I had a p. caerulea in a previous garden (north of Glasgow, cold and
wet) which in a cold winter ( more minus than 17) would die back to ground
level; but spring back up from underground the following year. Its roots
were under a big sandstone slab at the doorstep which probably saved its
life. It was still there and thriving last time I looked, must be well
over a quarter century old by now .

P. incarnata would definitely do the same. I spoke to a couple of
nurseries who couldn't keep it alive, had the same problem in two
places, and succeeded only when I planted it in the rain shadow
of the eaves.

I suspect that there are quite a few 'tender' plants that would
do better under such conditions.


Regards,
Nick Maclaren.