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Ready to Start my First Grow - Need a summary of Temp/Humidity per growing Phase

2by4Rich

New member
I am missing the optimal Temperature/Humidity for each growth phase. I was hoping someone could provide that info.
My 2 by 4 by 5 feet tent is ready and I have determined I have control on Temp/Humidity, lighting, and Air intake/output.
I do have the optimal factors per growing phase for light conditions, nutrients, and CO2..
I will be growing "Monster Bruce Banner Auto".
I plan to germinate using Rockwool Cube placed towards the edge of 5 gallon smart pots to do low stress training. Media is "Bush Doctor - Coco Loco" and nutrients from "Growth Science Nutrients".
Any advice on the Temp/Humidity on a per grow phase OR some other advice, would be great. Thx.​
 
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Technically anything works. Though seedlings, clones and young vegitative plants do better with higher humidity(60-70%+). Throughout veg most consider optimal between 50-60%. It it when you are in bloom that high humidity can destroy a grow by letting the moisture in the air lead to mold and/or rot in your buds. During flower I believe most try to stay near 50% RH or less. Let's hear what other members have to say.
I'll try and find you a link. I hope you can find this helpful. :)
EDIT:Ok, here's a couple good reads for ya.
https://www.growweedeasy.com/humidity
https://www.growweedeasy.com/temperature
 
A couple of videos explaining the Vapor Pressure Differential and plant transpiration.

https://www.youtube.com/watch?v=DLUCdBJkJ6k

https://www.youtube.com/watch?v=a8mq9TtMvWw

And a couple of charts.

Cannabis LED Grow temps humidity.png
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Humidity targets.png
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Thank you so much! These charts are exactly what I was looking for. The Videos has open up a whole new area I didnt know about. Great learning!
 
I use the AC Infinity fans and they have an app that you can control them with. it calculates the VPD value but you can only target temp and humidity as far as fan control. It also lets you set up some automations. I've set up a schedule for the tent with the flowering auto and it works pretty good. Only have to check it for watering and later as the temp rises usually add some humidity,

1. lights off fan set for 80F and 78% humidity; temp slowly drops to mid 60Fs and RH will run at 78%
2. 15 minutes before lights on, start out with fan off with a small heater on. Heats up and RH drops a bit.
3. lights on heater off, fan off for temp, on for 66% RH, slowly start removing RH.
4. fan on for 75F but not humidity, Fan will be running for heat RH will drop
5. the final fan on at 71F and 60%. for the duration of the lights on. Fan usually running a constant 2 out of 10 speed.

This is with the colder temps in the room, about 65F and 50-60% RH
 
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The thing with thermometers is getting them to read the same. I have an IR gun but don't trust it for the one or two degree difference you would be expecting. And it usually shows almost the same temp. A lot depends on air flow. The bigger your lights and smaller the space will need large airflow to control that heat. But it will keep the leaf temp the same as the air temp and make the humidity too low usually.

Controlling the lights for temp is what to shoot for if you can as the VPD target is a lot easier to attain with lower airflow. This is in the winter when high humidity is usually not a problem and cooler temps make for easy cooling.
 
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