So I’m in week 6 and my plants are nice and healthy. No signs of tip discoloration at all. Here in Oklahoma the humidity stays crazy high. I have plenty of exhaust in the room, and probably more than enough air moving in the room, will it really matter if I see 58 percent? Or should I get it down quick? I figured if the air is constantly moving and not stagnant and still. Always running my exhaust now that I’m not running c02. Thoughts or suggestions? I know they say lower the humidity late in flower to prep for harvest. But even with my dehumidifier running over night, it never gets under 49. No standing water in the room
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58% is pretty well in the sweet spot as long as your air circulation is on point and your temps are around 80f or so. the higher your temp is, the higher humidity your plants can tolerate. look up vapor pressure deficit. you dont need to adhere to this by any means, but it will give you a better idea of what plants can tolerate, what conditions help them do their business, and danger zone rh levels (high or low). for reference: one of my tents (led lights, no co2) runs at 85f and 70ish% rh and produces excellent results. my sealed rooms (de hps lights, 1200ish ppm co2) run 80f and 63ish% rh also with excellent results. i have run 78f and 55% rh with excellent results. ive seen rooms with pretty out of whack temp and humidity still produce respectable results. cannabis is a soldier of a plant, it doesnt require the doting and babying that most people seem to think it does.
tl;dr: 58% is probably good to go. keep your air moving adequately and youll be fine
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That’s not an issue but as temps go down with lights off the humidity will go up. Just keep your night time humidity in check and you should be fine.
I have to use a dehumidifier at night to keep mine around 50% otherwise humidity gets in the 60s
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I’m OK also, and I struggle with humidity in the summer. We live in an old house, and it’s not what you’d call, tight. I got hit with some PM last year and it was brutal, I had some Blueberry, and Afghani plants that it wiped out. For me, 60% is getting up there. I increased my airflow quite a bit, and I got a small dehumidifier. I recently bought some UVB lights from Solacure for my flowering tent. I’d been thinking about it for a while anyway, and June’s right around the corner. 
Good luck man. 
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Let me know how you like the uvb lights. I might have to do that. My portable ac has a dehumidifier in it, but doesn’t work all that great.
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What part of Oklahoma are you from sir? I’m in 5he tulsa/sapulpa area. If you’re ever down to smoke a doob let me know. I enjoy networking and making friends with other growers.
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We’re not that far apart man, I’m 7 miles south of Muskogee. It’s always good to meet a fellow head, share a toke and a smile. We don’t get up to Tulsa a lot, we do a Sam’s run every now and again, but yeah. I think we should burn one. 
Next time one of us is headed in the other’s direction, we’ll have to make some plans.
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Oregon is amazing. Oklahomas bud can’t hang with any of this stuff. Even their low grade thc buds 17, 18 % blows away our stuff testing at 26
I’m just starting to struggle with humidity issues. No way can I run a dehumidifier. Turning my exhaust system and all fans to 24/0 tonight. Also put in a new air filter into the furnace and turned the furnace fan on. It’s nice enough now that we have all our windows open. Hoping all this helps to drop the rh.
Its 85% right now, but it’s raining. Supposed to go back down to 50%-60% by tomorrow evening.
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my grow will never reach perfection but i keep trying, 45% humidity is what i aim for while flowering, higher when veging higher still when germinating
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