Ok, so, don't install a humidifier. Great! I won't. This GH will have about 6hrs of direct sunlight. My plan is to place my heat hungry trees in there like Black Jack, Tx Blue Giant, Black SPanish, Black Maderia and a few others. I also have a small 6x8 GH. That dude is in direct sunlight. I plan on covering it with shade cloth this year and using it too. Thanks for all your help.