Atsa nice! Persumably you have a liner that keeps the runoff from entering the bog? Otherwise there could be future trouble from the marble chips. Everything seems fine as frog hair now though. How will you overwinter the bog?
not sure of the zone but i don't cover it at all. Some leaves cover it a bit but nothing at all. The live is 6mil plastic with no drain holes. I have found that in the dead of wint I have put a thamomiter in the ground at diffrent depths and it never goes to 32 at 2 inches it is about 36 when it is 20 out and at 6" it is about 38. at 12" and below it stays at 38. I have had a string of days that it was in the teens for weeks and you guys see they allo came back just fine.
Tamilin if you read this I do have some pitchers if you want them. Let me know