Flower stage humidity question

My Autoflower is on day 47 and flowering someone told me not to change my humidity and temp set that I was currently using which is 83F and around 50-65 RH… How Accurate is this

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Going off memory here but I think your vpd is high? Again going off memory but if you could keep like the humidity close to 50% and get temps down to around 72 you’d be almost ideal I think :joy:. Still trying to get my environment dialed in so I may be off.

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83 is a little warm unless you’re supplementing with co2. I’d shoot more for a temp of 75 and an RH of 50%.

You’ll still get fine bud at 83 but if you want to get the most out of your tent that’s a little warm.

In terms of VPD, fantastic on paper, but it can be a brutally tuff target unless you’ve got incredible environmental controls.

65% RH is taking a risk imho…mold, PM

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I’m not using co2

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83 is at the top of the temp range and I’ve ran a few at 85 with no harm. I would definitely get that RH down to at least 55%. 45-50% would be ideal :love_you_gesture:

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When growing autoflowers in flower that’s exactly where my relative humidity and temperature are. 50% RH 73°

They love it

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Most plants will love higher humidity. Just my O2 I don’t worry about that till about week 4 of flower my self. And for temps. I can only speak for my self. I hate to see any thing under 78 degrees.80 - 84 is my sweet spot. I run in the high 80s and low 90s in the summer. It has yet to effect a grow. With temps hitting 100+ every now and then. I would just make sure you use a fan on them :grin: I would rather see crazy high temps than low. I don’t chase numbers for the most part, as it only leads me to trouble here Till they show me a problem. I just let them be :grin: Those are looking good. Also, having other smaller ones in there. the extra humidity will be good for them. Again. just my O2 here

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So wait until my flower start forming real buds until I lower the humidity?

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If it was me I would. This is a page from one grow. With my temps and humidity. I don’t have the notes from every grow on here. But have a folder with notes like this for every plant I have done. So a few folders lol I will look through and find a page that shows about where you are. I run a de humidifier once I see decent buds. Un less I have big dense buds. I can get away with out the dehumidifier. If you have one. I would use it once you are farther along :grin:

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Appreciate that bro and with my environment I can get my humidity down to the low
30’s without an humidifier… just don’t want to get bud Rot and all the extra I’ve been hearing about lol

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This what I have my environment set to now

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I would be happy with that. Some thing I learned early on. When you are about 3 weeks or so out from finishing. Every now and then. Snap a few pictures of the plants with your flash on. With the tent lights off. I do this with photos as well. It allows me time to down load them onto my pc and blow them up to stare at them. 99% of the time. If you have any bud rot starting or there. You will see it. Where under the lights. You would probably miss it.

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Excellent info my friend. @Not2SureYet

It’s amazing what you can pick up when you zoom in.
Works in veg too for those of us that are optically challenged. :grin::v:

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@Oldguy I use a black light when drying also. It shows the plants as purple under it. And when they start to dry. You can watch them turn back to green :grin: and this is why I do the pictures since I figured this out. my eyes are not what they used to be either.

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My farm values at the moment… its warm outside tonight (im in the south) but with the school as full as it is , im stoked with these numbers. (Theres 17 in there)

The high humidity and temps are for clones and seedlings atm…


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45 to 50% humidity in flower. Temps from 65 in off to 82 degrees on. This is just what’s working for me. I run a dehumidifier and humidifier in tent to dial it in. Ac Infinity controlled equipment and tent.

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Here is a chart to show how mold grows at different temps and humidity.
Screenshot_20231223-071442_Chrome

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Not sure i follow this - why would you hate to see temps below 78?

90’s, 100+ temps that high seriously hurt several aspects of cannabis flowers…those temps are way too high even with co2.

Less fragrant flowers, lower potency, hermi’s - all at an increased risk at those temps.

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Here’s your VDP chart.

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@StickyFrostyBuds yep :grin: Once I get to mid 70s. things are ok. But I do much better with higher temps.
I don’t like the 90+ but I only see those for a few days here and there in the summer. I would take 85every day if I could. I cool down to around 60 - 64 at night. Mine just seem happy in that window. Definitely not less fragrant. If I put any in a zip lock bag. You are still going to really smell them. For potency. I haven’t had any complaints. @Myfriendis410 has tried a lot of what I have grown. As to hermis. I have been lucky there. And know there is a risk there. I am not running A/C for the plants though.
I would love to have some autos hermi. @Myfriendis410 had a few autos I gave him do that out side. I got a ton of good seeds from them :grin:
I am not saying every one would want to follow me. But if I saw low to mid 80s every grow. I would be stoked. :grin: I do know that I am probably not getting the super frost others get. But the potency is still there. I appreciate you pointing things out though. I am sure it will help others out. I got things dialed in for how I grow a long time ago. Not that the weather always wants to play nice :laughing:

Thanks @Caligurl I actually fall in line with most there. I like a little higher humidity till the end of flower too :grin: I only offer limited advise most of the time. I know my way is not in line with most growers. But if it works. Don’t fix it :grin:

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