I'm in Sacramento, Zone 9 with 6 very young Ensete Maureliis (plus a Ventricosum and a Kru). Night time temps are beginning to dip below 50s--42 last Sunday night.
I made a simple DIY banana blanky last night:
1) two 55-gallon trash liners.
2) I cut open the sides and tops and laid them end to end;
3) taped them together
4) placed a U-haul moving pad on top
5) cut tiny openings in both at equal intervals along the perimeter
6) threaded bendable thingies that hold plants upright on stakes (sorry, forgot what they're called ); allowed enough length so that I can easily attach the "banana blanky" to something
7) the finished project is a "waterproof banana blanky" that I can cover my young bananas with;
I huddled my plants together in a fenced corner, and used the bendable thingies to attach the waterproof blanky nails on the fence. I hope to keep them warm and dry this way--until they grow too tall.
Anyway, I sleep better now knowing they're snug as bugs in their blanky.