albertoburrito wrote:How do you revive sphagnum? I want to do it for fun I guess. I know it will take a long time, but I think it will be worth it. Also how much humidity does it need indoors? My house is around 40%. I want to grow it with my neps without a terrarium.
Growing Sphagnum in lower humidity like that is rather difficult, though it can be done. The problem is, the moss has an extremely high rate of transpiration so it dries out very quickly, and moisture fluctuations will stunt its growth. You'll usually have dry tips on the moss even if you water it frequently (which may not be good for the Nepenthes if you grow them together.)
As for reviving moss, it really depends on which brand you have. Better Grow revives pretty readily, and that may extend to other brands that source their moss from Chile. Spagmoss and other products from New Zealand and much more thoroughly sterilized so it's much less likely, but it still happens for me on a regular basis, even in open air. If you want to do it on purpose though, you'll want to put some moss in a sealed container or bag, keep it evenly moist, and wait...then wait some more. It could take 6 months or more, particularly with Spagmoss.