How Cold Is To Cold

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Thejoeybrown

Thejoeybrown

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I used to always run 76/73. Been running 77/68 noticed trichome increase with the cooler nights at least thats what I think lol Not 100% sure, always trying to figure it out too. Honestly I like to run warm through week 7 then drop cooler that last 2 weeks.
Ya see so we are on the same page. I keep my temps as 76/68.
I will let it get to 65 without turning a heater in but it’s rare. I do think a slight temp drop at lights out helps but I’m talkin when temp swings are more than about 10 degrees I don’t think that’s optimal for growth.
I’m actually right with you on your thinking.

I just don’t think dropping temps to low 60s or lower to get some purple is making the harvest any more potent or grow as much. If anything I think it slightly hinders it. But the colors are nice to look at.
 
Thejoeybrown

Thejoeybrown

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I used to always run 76/73. Been running 77/68 noticed trichome increase with the cooler nights at least thats what I think lol Not 100% sure, always trying to figure it out too. Honestly I like to run warm through week 7 then drop cooler that last 2 weeks.
I actually think 77/68 is about as ideal as it gets in my mind.
 
Toaster79

Toaster79

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I've got 68-73 at lights on and 50-55 at lights out ambient temps and my plants are thriving. But I keep their feet warm from 73 lights on to 85 lights out.

This is 150W calorique infra red foil at the bottom of my tent which sits on concrete floor in my basement where my temps hoover around 50 in winter

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jguit

jguit

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Not quite the truth. I had serious issues in flower wit temps around 55 at lights out.

Curious what issues you had? Perhaps, it was strain dependent or something else? I've done quite a few winter runs with lights out temps dipping into the mid 50's without any visible issues. Did it affect yield? Most likely but i had no way to measure this. Dont get me wrong, I'm in no way condoning low temps and if you can raise temps then by all means do so but i dont think there would be many issues, if any if everything else is in check. At least this was my personal experience. YMMV

Correct advice would be to get temps up but dont lose sleep if for some reason you can't.
 
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GT21

GT21

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Keep them above 65... But about 2 weeks before harvest dip them to 60 for 3 days and watch the magic happen while flushin
 
Daikokuten

Daikokuten

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Curious what issues you had? Perhaps, it was strain dependent or something else? I've done quite a few winter runs with lights out temps dipping into the mid 50's without any visible issues. Did it affect yield? Most likely but i had no way to measure this. Dont get me wrong, I'm in no way condoning low temps and if you can raise temps then by all means do so but i dont think there would be many issues, if any if everything else is in check. At least this was my personal experience. YMMV

Correct advice would be to get temps up but dont lose sleep if for some reason you can't.
Never had a problem either, doesn't mean it doesn't happen to others. It's all strain dependent really. I run my room purposely at 55 and none of the strains i have yield less or flower slower at those temperatures, i have tested it a LOT. But i bet the right genetics would get trashed by these temperatures.

Why do people think that air temp equates to root temp? My roots on average were at least 5 degrees higher in coco and peat and more like 7 or 8 at 60 degrees. And with dwc you keep the water warm by turning off chiller. My buckets stay around 66/67.

Chilling to 60 should be fine for most strains. Im sure you could shock a plant lower than that. And again, just test it. Almost nobody does. Even the most professional, peer reviewed textbooks have mistakes. If you live in a cold area and want to know, its very easy to test. Easy to test "side by side" if you have a veg and flower space.
 
Ryesty

Ryesty

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So I was able to keep my low temp at 65 last night so I went ahead and transferred everything from my veg. room to the shed. The temp outside got down to 22 last night so I’m now able to hold a 40 degree difference between outside and inside. Which has been my biggest issue so far with this new shed. I thought r15 would be good enough but it just didn’t hold up on the really cold wind blowing days. This r30 system seems to be doing it. Fingers crossed, I’m all in now
 
xavier7995

xavier7995

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Below 65* and the foot zone shuts down. A shut down root zone stops.plant growth
I battled this my whole last grow. It was the suck.

Edit: I was down in the 50s and couldn't get the temps up. Very slow growth with bad yields, a few strains never filled in properly. Oh well, luckily it is warming up.

Edit @Smerb that is a great idea. Didn't even know those existed.
 
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Freshone

Freshone

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Something i have done over the years is put down a sheet of foam insulation on the floor as an insulator,when you keep the soil off the cold floor itself it make a huge difference in heat transference.
 
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