New Grower First indoor grow: LindaSeeds GG#4 and Gelato 33 under Mars SP3000
- Thread starter WildBill
- Start date
MOB
Dream World
Do you follow VPD?
hightimes.com
Understanding Vapor Pressure Deficit | High Times
Lately a new buzzword has permeated the upper echelons of the cannabis world. That word is VPD or Vapor Pressure Deficit. With help from Skye Hanke over
hightimes.com
Do you follow VPD?
Understanding Vapor Pressure Deficit | High Times
Lately a new buzzword has permeated the upper echelons of the cannabis world. That word is VPD or Vapor Pressure Deficit. With help from Skye Hanke over
Nope! That's sorta new to me. Makes sense! I've read about it MANY years ago, but since I've always grown outdoors, it really didn't matter to me because of little control of the conditions.
Something that's bugging me, maybe it's nothing. Seemingly, water usage has slowed. Maybe it's just that I'm learning to properly saturate the soil. Maybe it's that with the combo of lower tent temps and increased humidity.
I switched the timers over to 6AM to 12 midnight yesterday due to the cooler overall temps. It's been roughly 29 hours since I watered and fed. When checked a few moments ago, all three were still towards the upper end of "Moist" on both of my soil probes. Both cleaned with 1000 grit sandpaper before usage. Moisture levels were even at all levels on each pot with naturally the top levels being less moist, but no levels were "Wet".
Buds are fattening up and there is still upwards growth.
With MOB's question about VPD, the seemingly lower water usage makes perfect sense!
Let's see if the changes I just made to the grow room and tent will get the girls better aligned with the VPD chart. I slowed the exhaust fan and shut off the central a/c vent to the closet. That may raise the humidity due to transpiration though, but we'll see. I'll play around with some now that I have something to go by!
Thanks again MOB!
Damn this site is great!
EDIT .......I just turned on the a/c for a while to lower the house relative humidity and adjusted the fan back up slightly.
Gain Express Soil Ph & Moisture Meter 295mm Long Electrode
XLUX Soil Moisture Test Sensor
I switched the timers over to 6AM to 12 midnight yesterday due to the cooler overall temps. It's been roughly 29 hours since I watered and fed. When checked a few moments ago, all three were still towards the upper end of "Moist" on both of my soil probes. Both cleaned with 1000 grit sandpaper before usage. Moisture levels were even at all levels on each pot with naturally the top levels being less moist, but no levels were "Wet".
Buds are fattening up and there is still upwards growth.
With MOB's question about VPD, the seemingly lower water usage makes perfect sense!
Let's see if the changes I just made to the grow room and tent will get the girls better aligned with the VPD chart. I slowed the exhaust fan and shut off the central a/c vent to the closet. That may raise the humidity due to transpiration though, but we'll see. I'll play around with some now that I have something to go by!
Thanks again MOB!
Damn this site is great!
EDIT .......I just turned on the a/c for a while to lower the house relative humidity and adjusted the fan back up slightly.
Gain Express Soil Ph & Moisture Meter 295mm Long Electrode
XLUX Soil Moisture Test Sensor
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Well, much better.....................61% humidity and 75*F
Hunidity is gonna be high for quite a few days here.................93% and 66*F outside at the moment
Hunidity is gonna be high for quite a few days here.................93% and 66*F outside at the moment
Well, the 15 gal GG#4 is showing her stuff with putting some bulk to the buds. Makes me excited.........especially with the time left on this girl.
15 gal GG#4
Yep! It's a cool toy and tool!
"What the hell? You're easily amused aren't you?" ......................only a select few of you will fully get that!
....................and NONE of you will FULLY get it if you have to Google it! 
I like this one with the profile
15 gal GG#4
Yep! It's a cool toy and tool!
"What the hell? You're easily amused aren't you?" ......................only a select few of you will fully get that!
....................and NONE of you will FULLY get it if you have to Google it! I like this one with the profile
MOB
Dream World
Dehumidifier might be in order, in your stage looking for even lower humidity..... Water usage will be less with higher humidity - also consider adding another fan or two, blowing up under canopy!
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Yeah, It looks like I'll have to do that. It's back up to 65% this morning.
I just completely forgot about VPD. It bugs me that I didn't figure it out and remember about it. It was just one of those things that I thought I'd ever have some control over in my gardening life.
Thanks again MOB!
MOB
Dream World
I have a big dehumidifier controlling room and a smaller one in the tent, if needed, and lots of fans, like five fans currently ......
Folks think about soil and pot size, watering etc but often overlook humidity and wind - I suspect wind is the biggest overlooked item .....
Most welcome sir!
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