Thanks everyone for the kind comments!
Barb, perhaps 1 m of snow is beneficial for a few days but for four months? Actually in January we got more than two months amount of snow.... And February was three time colder than usual.
Andy, this nana is two years seedling from the
http://www.koehres-kaktus.de/ as well as the most of other seedlings I have except of the hybrids from Tim...
Chad, Cameron, Marceli, thanks you guys for your comments too!
As you know I had a bunch of yucca plants inside of unheated GH. It was too much unheated!
So what's happened to them:
1. Gloriosa green form is OK. Two variegated forms are OK too.
2. Recurvifolia green form is OK, the banana split has some leaf damage.
3. Rostrata sapphire sky three years seedling are OK
4. Thompsoniana is OK
5. Elata is OK
6. Glauca is OK
7. Torreyi is OK
8. Intermedia is OK
9. Pallida is OK
10. Joshua tree is OK
11. Faxoniana is dead
12. Baccata is OK
13. Agave parryi and havardiana are dead
14. Hesperaloe parviflora (even small seedlings) and funifera are OK ...
Any comments?