Around the first or second week of November, I am going to dig up the plants and trim the leaves off my plants and store most of them in my outside Bldg. which is not heated...There is a refrigerator and Freezer in there and I think they give off a little heat, plus the bldg. is insulated really well !!
Used it last year and didn't loose a Plant. Oh yea, it's not dark in my Bldg. and the Plants have no problems going dormant. Hope this helps!!
Good Luck,
Frank