bloomingdale
Member
How important is it for the nighttime temp to be lower than the daytime temp? If so what is the optimal swing? 3, 5, 10, 15 degrees?
Nighttime temp swings
- Thread starter bloomingdale
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sheik_yerbouti
Member
Lots of great articles and different opinions on the subject. I've read that a good 10deg temp swing is best for fastest growth however by keeping the night temp closer to your day temp you can keep your internodes tighter if such is warrented or wanted.
bloomingdale
Member
thanks Sheik. I meant to say that i'm really referring to the flowering period after stretch. what about that time?
It's usually lower anyways once the lights go off, however, it doesn't have to be lower. I have noticed you get more frost when the lightout temps dip into the low 60's. I've heard others say there shouldn't be more than a 10 degree differential between day and night, however, I find this not to matter and have had it to happen often without any issues. Think about what happens in nature...there is no guarantee of a 10 degree or less temp differential. These things are very resilient..
D
DHF
All valid points Bud......except.....
We`re creating the most optimum environment and watts per sq ft "inside" not outside , and ambient temp differentials between lights on/off have been determined for more yrs than I can remember to be most effective with 10 degree variable or less if environment can be dialed as such for max returns by end of cycle.....and hey....
The "more frost" production thingy is a myth with lower lights off temps , and I`ll be gladta explain......In late bloomage the plants job is to suck juice for lights off swellage , and yeah.......
Plants flower and swell at night.....JUST like "outside".....but.....The only other thing they do during lights on till end of cycle is pump resin for survival mode in extreme heat/light exposure from HID lighting to mimic the big Metal Halide in the sky........and THAT`S where the frost comes from......and.....for the record....
Once I knew what I was doin after yrs and yrs , I did in fact manipulate my lights on/off temps further during the last 2 weeks before chop to kill excess chlorophyll and bring out the anthocyanin in each and every plant for those "fall" colors everyone drools over , and during lights on I "raised" temps and slowed airflow to stress the plants into pumpin even more resin as a defense mechanism........but......
Unless yas`ve have run monocropped and dialed bitches , it`s better to keep things within a 10 degree variable for dialed results and more bottom line returns with different varieties runnin at once........anyways....
My 2 cents from all them yrs.......Hope that helps.....
Peace....DHF.....
......bloomingdale
Member
So if my lights on temps are 78-80° is it safe or beneficial for my lights off temps to be only 3°-5° less?
farmhouse cat
Member
DHF, remind me of why we try to keep day and night temps as close as we can?
Right now in my sog room i have been able to keep the day and night temps within 4-5 degrees. (lights on from 74-78) (lights off from 70-74) So far it has kept my stretch down to a minimum, but i think its mainly because of the lower temp range im keeping? In sog of course we want as little stretch as we can get.
But in the vertical grows dont we want stretch? So if one was trying to promote stretch then a bigger temp swing would promote it?
Right now in my sog room i have been able to keep the day and night temps within 4-5 degrees. (lights on from 74-78) (lights off from 70-74) So far it has kept my stretch down to a minimum, but i think its mainly because of the lower temp range im keeping? In sog of course we want as little stretch as we can get.
But in the vertical grows dont we want stretch? So if one was trying to promote stretch then a bigger temp swing would promote it?
Yes!
Keeping your differential under 10 will maximize yields too, quite a bit.
Anyone that says different, hasn't tried &/or paid attention.
No problem dropping the lights off temps the last couple weeks like mentioned either.
I've found it adds some sweetness, as well as the beautiful colors.
J
JimmyRow
I always tried to keep temp swings to a min, here's my current situation. Can't seem to do any better than this...
Lights on 78-79. Then lights off temps drops to 62-64. Within two hours we are back up to 67. Then temps max out at 69-72 a couple hours later and hold til lights on.
Bad??
Lights on 78-79. Then lights off temps drops to 62-64. Within two hours we are back up to 67. Then temps max out at 69-72 a couple hours later and hold til lights on.
Bad??
farmhouse cat
Member
I have the exhaust hooked to a temp sensor. It runs full time during the lights on to keep the temp at the setpoint. But at night the exhaust is usually off, unless temps creep up then it turns it on to cool the room. I also put a space heater in there to come on if it drops below 70.
Seems to be working pretty good.
I would think 62-64 lights off temps might be too cold and slow the plants down. But it also depends on what week your in.
Id say it depends alot on when, and growing medium etc. I know i just screwed up my whole crop, by letting the room get down to 14c during lights off for the first 3 weeks of flower. Stunted em bad, hindering water/food uptake. Really killed my yields. But im in coco, which i think is more vulnerable to cold root temps.
Stay Safe
Stay Safe
^^ I agree I feel like this happened to me also ..
My roots got super cold ! ..that's we're I think it stunted them ..I've had better yields when I run the cold reverse ..cold air during lights on + air from the room lights off ..but during light out its a humidity battle when the cold air shuts off and the room air comes in ..if I keep lots of air flow it works out fine ..
I thought I read somewhere that frostiness was a production of the plant to protect itself from cold Or uva/b rays ?Is that incorrect ?
Also I didn't see color discussed 2 much ..we all kno some plants color in any temp and others need color night temps to do it ..I persoanlly like when my ogs change from green to purple and the undersides of my leaves usually end with a purple tint ..in cold temps ..
My roots got super cold ! ..that's we're I think it stunted them ..I've had better yields when I run the cold reverse ..cold air during lights on + air from the room lights off ..but during light out its a humidity battle when the cold air shuts off and the room air comes in ..if I keep lots of air flow it works out fine ..
I thought I read somewhere that frostiness was a production of the plant to protect itself from cold Or uva/b rays ?Is that incorrect ?
Also I didn't see color discussed 2 much ..we all kno some plants color in any temp and others need color night temps to do it ..I persoanlly like when my ogs change from green to purple and the undersides of my leaves usually end with a purple tint ..in cold temps ..
D
DHF
In all my yrs of croppin I never got much closer than 10 degree variables during lights off/on across the board for dialed results , and the reason behind it`s simply less stretch and more node stackin with dialed environment.........
With Equatorial Sativa`s that grow 20' in the wild and have donkey dicks colas 3-4 ' long once they finish is because of the less than lights on and lights off temps that stack nodes and develop said nugs......
FHC.....All about stackin nodes and laterals in Pre-veg , and settin bitches loose once dialed and fillin in that sideways canopy ftw after the flip and end of stretch to be all they can be by end of cycle......
Good luck....DHF....
......
J
JimmyRow
I'm digging in coco. Right at week 5. Think I'm gonna add some more insulation under em, next week I'm adding more exhaust, and will be blowing air from the veg room on to the roots. Doin what I can for now...thanks for all the input
farmhouse cat
Member
Thanks Fred.
Heres a pretty good article i just found.
http://www.cannabisculture.com/articles/1536.html
Heres a pretty good article i just found.
http://www.cannabisculture.com/articles/1536.html
Found it,I copy/pasted it a few years ago,it was an article in the 2006 High Times Seed Buyers Guide....
https://www.icmag.com/ic/showpost.php?p=2587554&postcount=6
