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Vertical first attempt

mrktwiz

Member
OK I'm not afraid to look stupid because I want to learn this

OK I'm not afraid to look stupid because I want to learn this

You must spread some Reputation around before giving it to DHF again.



This is solid information in plain English coming from a guy with more experience than most of us... maybe all of us. Water is what gives us life. So many chemical reactions are dependent on it... Higher metabolic rate= higher water consumption... Low RH means the plants are going to lose more water through transpiration. RH can be a limiting factor in growth. DHF knows this, so you guys should listen...

OK Bobble....I'm just going to ask because I am just not that smart, what is RH? Room humidity? Resident humidity, I am trying to understand VPD vs Humidity I believe these are two different things and I am trying to apply this to my stadium grow, currently (since i am flowering) I keep my bud room at a room humidity level (RH?) lower than 50% and I'm running my de-huey 100% of the time due to the storms hitting Santa Cruz and it's like 99% humidity here right now PLUS I get a little water seepage into my grow basement because I kinda live in a flippin rain forest (very wet micro climate here).

Can you put VPD into layman's terms for me to apply to my situation?

Thank you,

Mrktwiz
 

ChronMan

New member
very nice grow mate! do you rotate those pots for 360 degree growth.?
or you just training the growth like a stadium effect.? nice.
 

Hydrosun

I love my life
Veteran
RH is "Relative Humidity" it is expressed in a % of total possible humidity at any given temp.

Once the RH = 100% you have rain / condensation. RH at 50% means the air has exactly 1/2 of the amount of water it could hold before the water condensed out of the air.

I am sure the plants in hydro respond differently than plants in soil at the same RH. I believe this because hydro plants have access to more water / unlimited water to push through their leaves but soil plants are very limited to the amount of water they have and can move from the roots.

I have heard anecdotal reports that higher RH for veg and the first few weeks is better, and that seems to be what DHF is saying.

I think each strain and growing style have their temp and RH sweet spot and it would be neat to so control / dial your room that you could hit the sweet spot daily. Dare to dream.

:joint:
 

bobblehead

Active member
Veteran
it would be neat to so control / dial your room that you could hit the sweet spot daily. Dare to dream.

:joint:

I'm gonna go ahead and make that dream a reality. After reading this, I'm going to implement a fogger in my new rooms. The HUM-1 can increase or decrease humidity, so I'll get one of those and plug the fogger into it. Hell, maybe I can even do a side by side, the difference between 50% and 70-80%. You do have a good point Hydrosun, DHF grew in smart pots with coco... your RDWC plants have an unlimited supply of water! ha ha... But they still have to process it, and that takes energy.

Check this out... We carry CO2 as carbonic acid in our bodies... H2CO3= H20 + CO2. Now I'm a little rusty on plant biology, but I'm betting it's not that different. If the plants are working to replace water lost, then that's less energy available to do other things... I'm gonna have to break out my biology book...
 

bobblehead

Active member
Veteran
OK Bobble....I'm just going to ask because I am just not that smart, what is RH? Room humidity? Resident humidity, I am trying to understand VPD vs Humidity I believe these are two different things and I am trying to apply this to my stadium grow, currently (since i am flowering) I keep my bud room at a room humidity level (RH?) lower than 50% and I'm running my de-huey 100% of the time due to the storms hitting Santa Cruz and it's like 99% humidity here right now PLUS I get a little water seepage into my grow basement because I kinda live in a flippin rain forest (very wet micro climate here).

Can you put VPD into layman's terms for me to apply to my situation?

Thank you,

Mrktwiz

you answered your own question with that great info you posted bro!

How does VPD compare to relative humidity?

Figure 1 shows how VPD relates to the customary thinking about humidity. Higher VPD means that the air has a higher capacity to hold water, stimulating water vapor transfer (transpiration) into the air in this low humidity condition. Lower VPD, on the other hand, means the air is at or near saturation, so the air cannot accept moisture from the leaf in this high humidity condition

You just have to understand osmosis. If the air has little water in it, it has a high VPD, and it's going to try and take some water from your plants to even things out. This is just water lost from your plants. They now will have to draw up more to replace it.

Don't worry too much about VPD and the technical terms. The important thing to take away from this conversation is that during the stretch, you want to keep the RH (Relative Humidity) high, 70-80%. That will make sure the plants have plenty of water for growth. When bud formation really starts to pick up, you need to cut the humidity to around 50% to prevent bud rot.
 

StealthDragon

Recovering UO addict.
Veteran
Wtf!? Is Aerohead giving a test on humidity and VPD on friday or something? Is it ICmag finals time already?

I just came in to stare at some pics and drool a little bit, but I feel like I should be taking notes. :)
 

mrktwiz

Member
ok if I am using the calculator correctly here is my equation to hit max VPD in my room;

Temp - 78 degrees

RH - 59%

= VPD (ideal) 18.1 kpa

All I think I need to do is let my humidity rise about 8-9% and then I am dialed in.

Interesting
 

bobblehead

Active member
Veteran
ok if I am using the calculator correctly here is my equation to hit max VPD in my room;

Temp - 78 degrees

RH - 59%

= VPD (ideal) 18.1 kpa

All I think I need to do is let my humidity rise about 8-9% and then I am dialed in.

Interesting

That's correct, for your late stage flowering... 75% for the stretch. Thanks for the info Billy Liar!
 
D

DHF

Guys......I just fell into this shit where I live.........Gojo/Spurr ran all that VPD technoglarb by me at the Cabana awhile back about why my plants grew so explosively with high relative humidity at least 70%...........Bobble gets it.......

Thanks Billy , for a more understandable version.......

Hydrosun......I totally agree with you on soil plants transpiring and uptaking nutrients at a slower rate from hydro setups , and higher RH might be counterproductive if room temps weren`t in sync with the plant`s nutrient uptake and transpiration rate......

Mrktwiz....It took me awhile ta wrap my head around the concept that actually helped me grow bigger plants faster , but it`s best ta not stress too much about it , and do the best yas can to control environment lights on and especially lights off when RH goes through the roof with buncha plants sweatin.....

Back when I ran krusty buckets , folks were usin foggers to up RH , and I was runnin dehueys ta keep it below 80-90% .....

I`m just here ta help , and tryta keep folks from fukin up as much cuz this shit we do`s kinda costly if done on a regular basis , and somewhat of a return on investment is required at some point in the game huh ?...........

Ya`ll take care.....DHF.....:ying:.....
 

Aerohead

space gardener
Veteran
For some reason I can't upload pics, gives me a data path error. I have tried 4 PC's and 2 diffferent internet connects, I am trying to resolve the problem... Bummer got some juicy ones too..


Edit: If there is Mod reading this I could use some help, I get this message:

Failed to write file. Check disc quotas and permissions for the path: /data/web/icmag/icmag.com/www/ic/userimages/607/607685.picture

I also cannot contact ICMAG... I'm stuck
 

StealthDragon

Recovering UO addict.
Veteran
it's ICmag bro..there's a thread up somewhere about it..look in new posts you'll probably see it...kick back and smoke a bowl :)
 
Sounds like their server is having some issues... Too bad, I'd love to see those pics Aero! If you removed EXIF data (geotag's!) you could put the pics up on imageshack.us or something.
 

Aerohead

space gardener
Veteran
Hey Cheesebuds, good to see you!! Thanks yes I stepped it up a bit..

DHF, Glad you found the thread, Thanks for spreading your wisdom here, The RH help is much appreciated...

Thanks!!

Marlo....LMAO @ the huge powered doughnut... This is my new goal....Time to make the doughnuts..

ChronMan, Thanks for checkin in, I did think about rotating the plants but this would have to be manual since I don't have an automated way to rotate. I decided not to trust myself to consistently rotate the plants and trim the back sides off.

Greenthumbdub, Welcome!! Vert growing is a great experience, I am already blown away can't believe I didn't do this sooner...


Pics coming as soon as I can upload them, I think I am going to have to take new pics since it is going on 2 days and they have grown again since the last pics I was attempting to upload

Edit: I forgot to mention, I placed a humidifier in front of the passive intake to the room and bumped it up to 53% lights on. This will have to do for now, gotta be better than 30%, it was occasionally hitting 20%...
 

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