All that bark on top will only lower your ph and cause more of that yellowing you have going on. I would get it out of that bottle you have it in and put it in at least a 3 gallon pot or bucket asap. Roots don't like light and they are being exposed to it in that bottle. Don't waste your time wrapping it with tape, just transplant it and be careful. Cut it away with scissors if you have to. Good luck!