Firstly, I am not one to worry too much about humidity. I have two conditions - high humidity, these go into a wardian case with 90%+ humidity, and all others - these get whatever the conditions dish out. You really can't control the humidity outdoors (not in a practical means) and I would recommend not worrying about it. Lots of mine get humidity from lows of 30% to highs of 60% based on nature, rainfall, humidity of the day, etc. They seem to do fine.