Optimal temperature, humidity and EC
- Thread starter Lavindo
- Start date
King Avitas
Well-Known Member
Well that depends. There are scenarios that change those parameters form room to room and strain to strain.
A general rule of thumb for a basic set up is:
55% to 65% humidity lights on from seedling to mid Flower cycle, mid to late flower 40% to 50% humidity. Then for lights off, try to stay under 50% humidity with good air circulation from fans and that should keep most grows safe.
As for temps try to keep them under 85⁰f but over 75⁰f from seedlings to mid flowering cycle. Then you want to try to keep your mid to late flowering temps at about 70⁰f to 72⁰f to preserve terpenes. During lights off, try to stay about 10⁰f cooler than your lights on temp but don't go lower than 65⁰f.
Now you can throw everything I said out the window if you are trying to maintain VPD (vapor pressure deficit) or are using CO². But that's a story for another time.
LeastExpectedGrower
Well-Known Member
For temperature:
-80f for mats for germination
-75-85f for the duration for me is the goal. My lights-on temps are 82-85, Lights-out 74-79 generally.
For Humidity:
-Germination through the first 2 weeks of veg ~70% RH give or take.
-At week 3 I start pulling back humidity into the 60-65% RH Range.
-Once I hit mid flower I've been aiming at 50-55%
-After mid flower I taper down into the mid 40's.
During most of the grow I'm trying to keep the VPD somewhere in the range of .8-1.3, of course as your temps fluctuate between 75-85 but your humidity remains locked in within a few degrees, VPD also drifts in range.
I prioritize my temperature over my humidity. I've measured my leaf surface temperatures to be -2f or -2.5f from ambient when in the 80's in my tent, with lights on so having the heat up in the 84-86 range isn't a problem.
-80f for mats for germination
-75-85f for the duration for me is the goal. My lights-on temps are 82-85, Lights-out 74-79 generally.
For Humidity:
-Germination through the first 2 weeks of veg ~70% RH give or take.
-At week 3 I start pulling back humidity into the 60-65% RH Range.
-Once I hit mid flower I've been aiming at 50-55%
-After mid flower I taper down into the mid 40's.
During most of the grow I'm trying to keep the VPD somewhere in the range of .8-1.3, of course as your temps fluctuate between 75-85 but your humidity remains locked in within a few degrees, VPD also drifts in range.
I prioritize my temperature over my humidity. I've measured my leaf surface temperatures to be -2f or -2.5f from ambient when in the 80's in my tent, with lights on so having the heat up in the 84-86 range isn't a problem.