I've never cloned pepper plants but I have cloned, uhm, other stuff.. But should it be put in a humidity dome? When I did it, I took a cutting, dipped stem in rooting powder, stuck it in a peat disc and cut the leaves in half to reduce transpiration while it's developing roots and put it in a heated humidity dome. The humidity gives the plant moisture since there is no root system yet to supply it with moisture. I had roots in a week..