Burnt soil, peat moss, charcoal, tree bark and limestone. Also, at the bottom of the pot is a 4 inch layer of pebbles and some limestone. Orginally I was thinking that this was the best mimic of northiana's environment. Turns out it actually helps in draining alot. I hose my northiana until it becomes waterlogged (because my burnt earth wasn't filtered, hence the terrible drainage
) and it took a minute to drain off. Yet the plant didn't complain and seemed to like being hosed.
Also, I'm guessing that the pticher becomes bigger on a harder surface eg. the charcoal bits. Just something I noticed, but this claim might nor be true. When it's time to repot it, I'll see how extensive the root is
thanks everyone!