Running 90°F temps

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BurnzYzBudZz

BurnzYzBudZz

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Hotter temps = higher humidity. Always need increased airflow and increased water schedule when it’s hotter but I’ve ran my tent 95+. Check out VPD charts and keep the temp in line with humidity and you’ll be fine. Check my first grow log when I was battling hot ass temps with no AC in my garage. Keep it simple.
 
ComfortablyNumb

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Hotter temps = higher humidity. Always need increased airflow and increased water schedule when it’s hotter but I’ve ran my tent 95+. Check out VPD charts and keep the temp in line with humidity and you’ll be fine. Check my first grow log when I was battling hot ass temps with no AC in my garage. Keep it simple.
Yep. A VPD chart is very helpful. Just make sure to use the leaf temps and not air temp.
 
Kl420

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C
Hotter temps = higher humidity. Always need increased airflow and increased water schedule when it’s hotter but I’ve ran my tent 95+. Check out VPD charts and keep the temp in line with humidity and you’ll be fine. Check my first grow log when I was battling hot ass temps with no AC in my garage. Keep it simple.
Checked out your grow log, pretty good girls you've got there. I want to ask after which node Is the best time to top it off?
 
Kl420

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Update day 17:

The plants are growing pretty well, starting the fifth nodes in 3 plants, 2 on the forth node still and one has had a problem.

20210824 063917

I feel they'll be ready to be topped off in a couple of days and was wondering if its better to FIM or top them off? And how long to wait before up potting them.

The one plant that had trouble seems to be over watered and the roots have started to rot I think, today I changed the soil in it and didn't see much white roots.
20210824 063921

Is there anything else I can do to save her now? Hopefully it'll dry out and recover soon.
Here are some other photos of the girls. Jah bless these plants
20210824 063925


20210824 063906
 
BurnzYzBudZz

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This is incorrect. Warmer air holds more water vapor so hotter temps = lower relative humidity. This is why it's called relative humidity. It's relative to temperature.
At sea level, raising the temperature from 20C at 100% RH to 30C results in 55% RH:
1280px-PsychrometricChart.SeaLevel.SI.svg.png
😮 . Nice charts, please elaborate for us new growers.

*edited
That’s why I had said increase air flow, intake and exhaust. If he’s running 90+ Degrees, he’d want the RH 70+ with increase airflow. I’m talking from my experience. Gotta work with what we got.
 
Kl420

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😮 . Nice charts, please elaborate for us new growers.

*edited
That’s why I had said increase air flow, intake and exhaust. If he’s running 90+ Degrees, he’d want the RH 70+ with increase airflow. I’m talking from my experience. Gotta work with what we got.
Yeah now running a big ass fan and the temps are under control, only when the outside environment temps peak at noon its close to 87°F
 
PauliBhoy

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Nice charts, please elaborate for us new growers.
Sounds like you get the gist of it. RH is the fraction of water vapor the air can hold. Hotter air holds more water vapor than cooler air, so RH would drop with an increase in temp and visa versa. It's why RH is almost always lowest outside at the hottest point of the day and highest at the coolest point of the day.

Yeah now running a big ass fan and the temps are under control, only when the outside environment temps peak at noon its close to 87°F
That's fine for veg but you'll want to get those temps down a lot further for flowering.
 
Kl420

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HELP!! Is it normal for the plants to be drooping in the morning? Should I water them? Haven't watered in a week now
 
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Madmax

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Yes they do droop of a morning at times.when your plants are wilting from lack of water the petitole and tops of plant will droop .like hanging over lifeless..i have no experience using ffof but i gather pots are are pretty light at 7 days especially if its hot.roots wont grow into dry soil .
 
Kl420

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That
Yes they do droop of a morning at times.when your plants are wilting from lack of water the petitole and tops of plant will droop .like hanging over lifeless..i have no experience using ffof but i gather pots are are pretty light at 7 days especially if its hot.roots wont grow into dry soil .ood to know

Yes they do droop of a morning at times.when your plants are wilting from lack of water the petitole and tops of plant will droop .like hanging over lifeless..i have no experience using ffof but i gather pots are are pretty light at 7 days especially if its hot.roots wont grow into dry soil .
Thanks for the reply. That's great news, I just watered them afterwards and now they seem to be rising up again, must've been a sleeping situation after the light out period. And I cut the pot open in a panic to let the roots breath more. Hope all goes well here on
 
Kl420

Kl420

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It's day 19 and I topped 3 of the plants after the fifth node. One might have turned into a FIM situation, still not sure. Any advice as I wait to see the results of these toppings?
20210826 084908
20210826 084917

^this looks like I missed it
20210826 084930
 
PipeCarver

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Anthem

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That's fine for veg. Just be aware that during flowering you won't want it hotter than 76 day or night.
The temperatures you are running depend on several factors.
#1. If you are running LED's you should be about 81 to 82 form lights on. This is air temperature, which will lead to a leaf temperature of about 78 which is ideal for flower.
#2. If you are running HPS you should be at about 78 degrees, again this is air temperature.
If you match up the temperature and humidity with a good VPD chart and remember the VPD temperature is based on leaf temperature your results will improve.

The problem with running the VPD charts to the end of flower is various types of mold. There is equipment to combat the mold but rather expensive for someone in a small tent so your best bet is to start dropping your humidity as your flowers get larger. The larger the bud is the more likely it will be mold.
 
ComfortablyNumb

ComfortablyNumb

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That's fine for veg. Just be aware that during flowering you won't want it hotter than 76 day or night.
That changes based on humidity and other factors. Check a VPD chart for acceptable temps in various humidity levels.
If you do not have a way to cool the grow area, then the plants will have to adjust.
I have grown successfully outdoors in 90 degree weather. The ideal temps are 75 with lights on and 65 lights off, but it is not always possible.
 
Kl420

Kl420

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Wow thanks a lot guys, this is some vital information.
The temperatures you are running depend on several factors.
#1. If you are running LED's you should be about 81 to 82 form lights on. This is air temperature, which will lead to a leaf temperature of about 78 which is ideal for flower.
#2. If you are running HPS you should be at about 78 degrees, again this is air temperature.
If you match up the temperature and humidity with a good VPD chart and remember the VPD temperature is based on leaf temperature your results will improve.

The problem with running the VPD charts to the end of flower is various types of mold. There is equipment to combat the mold but rather expensive for someone in a small tent so your best bet is to start dropping your humidity as your flowers get larger. The larger the bud is the more likely it will be mold.
Yeah this great news, so I think my leaf temps are pretty good as I have been measuring the air temperature at canopy level all this time. According to vpd chart its all in the green zone now.
That changes based on humidity and other factors. Check a VPD chart for acceptable temps in various humidity levels.
If you do not have a way to cool the grow area, then the plants will have to adjust.
I have grown successfully outdoors in 90 degree weather. The ideal temps are 75 with lights on and 65 lights off, but it is not always possible.
Yup currently I am unable to reduce the temperature below the outside environment temperature because I don't have a AC but these days it's been monsoon season and temps have been cooler, hopefully it lasts beyond the flowering time. The tent is only a couple of degrees warmer than the outside.

Again thanks a lot guys, I hope this thread will benefit someone else in the future who is fighting high temps, I'll keep the progress updated for educational purposes.
 

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