Hi Yassir, I have grown nepenthes such as rafflesianna, mirabilis,
rokko, kampotiana (that's what I call it anyway), maxima and thorellii
in straight peat with a thin layer of spaghnum over the top just to keep
everything moist underneath, but I reckon that I might as well not even
have spaghnum there at all because it's so thin. These plants have been
growing for years with no trouble at all, but I do have them in big
fishtanks because it's not very humid where I live. So with these
plants, it should be ok. I haven't tried this for others though.
Kenny Leong.