VPD and Cannabis

Not bro-science, but defintely good science that is often warped by the peanut gallery's lack of education on relevant topics. Any feelings of inadequacy is purely caused by irrational insecurity. This isn't something you can just glance at and understand immediately. Biology and Chemistry, like many other complicated subjects, are learned in layers upon layers upon layers... if you don't have the foundational layers of knowledge, you cannot jump to the "3rd layer" and expect to understand it. This should not make anyone feel inadequate. We cannot understand all things in life and sometimes have to rely on the knowledge of others. With lab-precise environmental controls and elevated atmospheric CO2, it's a damn good idea to keep your VPD in a good range so that you don't waste all those other efforts and resources. 30C with approriate RH will result in the greatest amount of ATP production per day from photosynthesis. What is the best VPD? No fucking clue, and nobody knows this exact figure at this stage of the game. Large and numerous samples compared to a control group will be necessary, due to the matrix of possibilities of the variables involved. The range of suggestions are still a good ballpark to start and observe and adjust to what you see. VPD is also indiscrete. The same VPD at 20C is not the same resulting impact as that same VPD at 30C. So, don't think of it in that simplistic way. VPD on its own is incomplete information for most uses. For most of us in less controlled environments, it is still useful to know the basic relationships of VPD. e.g. a higher vpd needs a lower concentration of fertilizer over time, ceteris paribus. A high or low vpd can be an indication of high risk of pathogens.. A high vpd will inhibit transpiration at some point (CO2 intake). Understanding the basics of it, even if on faith, will help diagnose and deal with problems you encounter or help you avoid such situations in the future altogether. This stuff is complicated with many moving parts... easy to misinterpret when you don't have foundational knowledge.

For me and VPD .. it is something I’m trying to following as best as I possibly can, BUT honestly it isn’t always perfect and sometimes kinda off tbh. So, I try but I’m not going to beat myself up or panic about it either. I don’t have all the perfect equipment to be perfect all the time. Maybe somed

How so? Don't mistake the large acceptable VPD range to mean that VPD doesn't matter. Think of it like temperature for us humans. Whether it is 70F or 72F matters little for us, as long as we're not in the extremes of extreme cold or extreme hot, we are fine. Would you take this statement to mean that temperature doesn't matter for us humans? Surely it does but the level of acceptable temperature range is big enough that you have to make a concerted effort to fall outside it for extended periods of time. Generally, at least. It is the same thing with VPD. If you're not in a desert with unrelenting 0-10% RH and you're not in a rainforest with near constant 90-100% humidity, you're probably in the acceptable range. The way I see VPD is more of a guideline than a rule. If it's too low, I switch on the humidifier and if it's too high, I switch on the dehumidifier. It's way cheaper to control humidity than temperature over here but you can do whatever is easiest. If I'm like a few percentage points off from the optimal range, I leave it.

Gotta agree with the others, VPD does have a effect. Grey_wolf also has good points in other bro science myths. Some other ones to add onto his list. Milk does jack shit for WPM, Gnats will not hemi your plants. Ice Water last 48hrs does nothing. More curious why you feel VPD does not ass any positive effect, and what lead you to come to that conclusion. Maybe some sites and reference points if it was something you read vs something you dudected yourself.

VPD makes sense for every plant. It's the regulator of transpiration for the plants. Thats the same as saying light makes no sense for cannabis

you really need to read a book on growing cannabis mate vpd makes sense for most growers with an ability to absorb new knowledge and is not bro science bro science examples are flushing soil NOT RECCOMENDED 24hrs of Darkness before harvest DOES FUCK ALL Using flavor enhancers late flower ALSO DOES FUCK ALL

https://bucket.growdiaries.com/static/post/photo/105536/8425923_e56431d82bb548d3b9790aff3f692472_big.jpg Pressure conditions, like everything else to do with plants there is an optimal environmental condition that exist for a process, cellular transpiration is the nighttime opposite of photosynthesis, we try to follow a VapourPressureDeficit throughout the flower period which optimize transpiration. I attached a photo chart thingy , just make sure to check it every so often make sure your RH temps etc its not falling far outside the band.

Reply to what? The statement vpd does not make sense to cannabis, is just a statement and not a question. Of course it doesn’t ‘make sense ‘ to cannabis, they can’t read. If you are saying it’s bullshit then that’s a bold call to say only you think that and millions of educated people can make sense of it. If I’m still wrong then you must need it explaining . Vpd basically affects the plants ability to transpire.Temp and humidity dictate it. Temp humidity are real my friend . Very real. Non bro science answers can be given easily on here but asking a question that’sanswerable