In the dry winter I find that plants just won't veg very well. Jack the humidity up to around 60 (mid to high 70's temp) and watch the growth take off. The opposite is true, low VPD makes very slow growth. Humidifiers in the tents matter.
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VPD - yeah it maters
- Thread starter flylowgethigh
- Start date
DLI is very important also... Most dont realize that very high light intensity in veg is no bueno because you have the light on 18-24hr... So having strong light is not needed because you are giving it 2x as much time... Even half the intensity is still statistically the same photons.. You can dramatically improve your grow comprehending the importance of VPD/DLI,DIF, and diverse environmental exposures... Dramatic terpene improvement, and pest/environmental resistance.
Having the plants under super intense light in veg slows/stunts/inhibits them so much. You can put them under weak light, and stretch to the light until their preferred intensity essentially speeding up veg dramatically. So many strains are adapted to cloudy, poor environments, and grow/yield so much better under weak light.
For example, I started telling everyone GSC was the type that needed lower intensity or lower DLI, and the word spread fast. A commercial grower tried it mid grow, and got dramatic improvements so everyone jumped on board.. Improved many grows with that tip, i wish I coulda got some bud samples for that one lol
Having the plants under super intense light in veg slows/stunts/inhibits them so much. You can put them under weak light, and stretch to the light until their preferred intensity essentially speeding up veg dramatically. So many strains are adapted to cloudy, poor environments, and grow/yield so much better under weak light.
For example, I started telling everyone GSC was the type that needed lower intensity or lower DLI, and the word spread fast. A commercial grower tried it mid grow, and got dramatic improvements so everyone jumped on board.. Improved many grows with that tip, i wish I coulda got some bud samples for that one lol
Once the plant has vegged and has a bunch of leaves, the tent humidity seems to take care of itself as the plants digest a gallon a day. These little guys are still making roots, and need all the moisture help they can get I think.
I have no practical idea what DLI is, I just start sprouts at 18/6 at 185 umoles or so, and increase the umoles as the plant gets bigger. I end up around 800 umoles at the peak of flower. When I am trying to finish the plant I reduce the ON time, and reduce the power... mimicking fall. My trics and terps are nothing special, so there is much room for improvement here.
Being lazy with the environment is bad, and makes mid grade dope.
I have no practical idea what DLI is, I just start sprouts at 18/6 at 185 umoles or so, and increase the umoles as the plant gets bigger. I end up around 800 umoles at the peak of flower. When I am trying to finish the plant I reduce the ON time, and reduce the power... mimicking fall. My trics and terps are nothing special, so there is much room for improvement here.
Being lazy with the environment is bad, and makes mid grade dope.
Yeah thats what happened to me... PLUS low RH (low 40/30) and Temps (lower 70) because of winter.... plant was fucked up real fast...
As a beginner you think more light = more/faster growth... thats definetely NOT true.
Btw, even if plant looks great,it's still a waste of electricity to run lights at 100% from first day like some guys do. There is a reason most leds have a dimmer. So you can lower their power, and then you are able to keep them closer to the small plants for better efficiency. No point on keeping them on high and very far away to get same results. Wasteful and quite stupid in my opinion.
I have a plan for any low terp situation that might crop up with the hazes I m running now. I'll just spray a bunch or "true terpenes" on the stuff, and it'll be first class.
TychoMonolyth
Boreal Curing
Daily Light Interval
https://www.youtube.com/watch?v=JwtkHxv_3pU&t=132s
He also talks about best temps and humidity
Very informative.
SoSincere
Active member
I grew for over 10 years before I realized VPD is the most important aspect of growing, with humidity being king, followed by temperature.
My sweet spot in veg is 76-78F 68-70%RH (77F and 69% is perfect... plus u gotta love those two numbers... almost seems like gods plan lol!) with good indirect air circulation in the room.
Here is the secret to learning what your perfect VPD is for your room. Get a sensor push module which is the most accurate humidity reader you can buy for under $100 and it does the VPD calculations for you. It graphs the temp, humidity, and VPD forever and with that data you will discover your sweet VPD spot. I have 10 of these units and I feel they are a must for growers
My sweet spot in veg is 76-78F 68-70%RH (77F and 69% is perfect... plus u gotta love those two numbers... almost seems like gods plan lol!) with good indirect air circulation in the room.
Here is the secret to learning what your perfect VPD is for your room. Get a sensor push module which is the most accurate humidity reader you can buy for under $100 and it does the VPD calculations for you. It graphs the temp, humidity, and VPD forever and with that data you will discover your sweet VPD spot. I have 10 of these units and I feel they are a must for growers
| Leaves praying? THEN |
| Decrease VPD by |
| Lowering Temp |
| Adding Humidifiers |
| Decreasing Lights |
| Decrease air circulation/extraction fans |
| Weaker nutrients |
| Foliar Sprays |
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Where did that praying/drooping stuff come from? I started last winter by hanging tee shirts on the wall and spraying them with water. It works well cause the evaporation is self regulating. A lot of work and not automated, although a pump and inkbird could automate the process.
The company that makes a humidifier which you set the desired VPD on, and it controls the humidity based on the temp, will make growers better.
The company that makes a humidifier which you set the desired VPD on, and it controls the humidity based on the temp, will make growers better.
Hi can I ask you something? So praying leaves is NOT god as said I have read by a lot of other people that Praying Leaves are Happy plants... Is that wrong?
So u think praying leaves are neither extremely bad NOR super beneficial?
No, I think IF the VPD is good, there is no reason to belive they are a bad sign! So no reason to worry. But most people don't even check VPD or measure temps and RH with crap meters and then maybe they use a flawed VPD chart to relate those measurements with, and in the end their VPD is nowhere near as good as they think.
Switcher56
Comfortably numb!
It all depends... suppressing power generates heat.
Ok I see... so u definetely would recommend a good VPD defice OR good RH/Temp meters? Like for example if I have 60RH and 25C... how much could that be off would that be good anyway even with some low tollerance of the meters?
Can u link a good chart? What about leaf temperature while calculating VPD and so on... important or not? My leaves often 5 degrees C colder then air...
