Margaret and Veronique,
Thank you for your kind replies, hope, that i can answer your questions. Our small garden is behind the
house, surrounded by other gardens and houses, so the miicroclimate is not so good for the cultivation
of my beloved high alpine cushion plants. Many plants, which were no problem 20 years ago are no impossible
to cultivate for me. Temperatures over 33°C are simply lethal for them.
We live in a limestone region ( good for growing wine), so I created a small region with acid soil, this is also
the place where Mutisia spinosa grows.
The lowest temperatures were -14°C, only sometimes for a short time, but enough to damage and kill some tender
plants. I don`t know, if M. spinosa needs cold to germinate, in my experience rain and snow is also important.
Black plastic pots are probably the reason for losses by overheating of the roots by the sun, plunging or planting
as soon as possible are maybe better. Space in our garden is very limited, so I didn't make cuttings.