Settle this please. temp needs for LED

BBQtoast

Well-Known Member
Here's a question it's 35% here today, what should I set my lights on temperature to based on VPD for max growth?

I'd like to hear answers, that's not rhetorical, get your vpd chart out and the winner gets my dead plants in a week's time.
 

bEelzeBosS

Well-Known Member
My problem with the VPD chart is if I followed it, especially later in bloom my buds would rot...and I have great air movement.
 

rkymtnman

Well-Known Member
Here's a question it's 35% here today, what should I set my lights on temperature to based on VPD for max growth?

I'd like to hear answers, that's not rhetorical, get your vpd chart out and the winner gets my dead plants in a week's time.
according to that worthless chart, i'm supposed to run my room at 59F. lol. plants adapt.
 

twentyeight.threefive

Well-Known Member
I think the answer is that,

'Your exactly the type of grower who causes the op to have to ask these questions'

I've explained where your chart is wrong, backed up others growing far outside your vpd range in death zones and added topics you can go Google for a quick understanding,

Still waving that chart around is not doing your case any good, either you can get past this or good luck buckwheat I haven't got time to be stuck at your level for long.
Ok. Good luck. Lol
 

twentyeight.threefive

Well-Known Member
Here's a question it's 35% here today, what should I set my lights on temperature to based on VPD for max growth?

I'd like to hear answers, that's not rhetorical, get your vpd chart out and the winner gets my dead plants in a week's time.
You'd want to increase your humidity to balance proper leaf temperatures and RH to be in the best VPD range. If you insist on not increasing your humidity and leave it at 35% that's fine, I'm not saying you won't have good results, just saying you could have better.
 

rkymtnman

Well-Known Member
You'd want to increase your humidity to balance proper leaf temperatures and RH to be in the best VPD range. If you insist on not increasing your humidity and leave it at 35% that's fine, I'm not saying you won't have good results, just saying you could have better.
where does CO2 levels in the room come into play on the VPD chart?
 

Nwtexan

Well-Known Member
This seems pretty easy to follow to me. I spent the last few days reading VPD charts and getting a bit of a grasp. I find it pretty helpful as a baseline for my grow and it helps to take out the fuzzy difference between newer more efficient LEDs and older HID's.
Makes total sense and nice to see some science behind it.

Seems to me that a lot of folks have methods that have worked for them. Technology is allowing many of us to maximize our conditions in ways that the average grower couldn't a few years ago.

I would love to see some studies implementing increased levels of CO2 and how that would shift this. I am assuming that it allows the plant to transpire at higher temps and humidity, thus increasing growth. I wonder if it is linear or shifts at a different rate/ Way past my pay grade
 

BBQtoast

Well-Known Member
You'd want to increase your humidity to balance proper leaf temperatures and RH to be in the best VPD range. If you insist on not increasing your humidity and leave it at 35% that's fine, I'm not saying you won't have good results, just saying you could have better.

Can we agree those charts are shit now.

Now I do insist on leaving my humidity at 35, the plants feedback now instructs stoma to adjust size and without effort nature has now moved me to a better water use efficiency the same as at a higher humidity.
 

Wizzlebiz

Well-Known Member
Who's testested 40% against 45%% against 50% and so on?
If i grow two clones next to each other they aren't the same so how any percy grower can put what ever difference down to humidity in particular is bollox.
Somone above said weed grows in any conditions, loosely speaking that's fairly accurate, they grow from Siberia to the equator.
Thats true but whats grown on the equator won't do well in Siberia. Strains and conditions matter greatly.
 

BBQtoast

Well-Known Member
[/QUOTE]
Thats true but whats grown on the equator won't do well in Siberia. Strains and conditions matter greatly.
Siberian strain might do well on the equator though, happened before true story.

It took 50 generations for a drug type to revert back to a wild type in tests.
 

Wizzlebiz

Well-Known Member
[/QUOTE]

Siberian strain might do well on the equator though, happened before true story.

It took 50 generations for a drug type to revert back to a wild type in tests.
[/QUOTE]
That I could see. I would think it would be easier to go from cold to hot instead of the reverse.
 

BBQtoast

Well-Known Member
Siberian strain might do well on the equator though, happened before true story.

It took 50 generations for a drug type to revert back to a wild type in tests.
[/QUOTE]
That I could see. I would think it would be easier to go from cold to hot instead of the reverse.
[/QUOTE]

I read it acclimatized easy, it was in the history of its ancestry I read that bit where it changes in 50 generations.

It doesn't like the cold, Siberia probably produced a lot of hemp in summer, I'm not sure it ever domesticated these latitudes naturally.
 

Star Dog

Well-Known Member
Thats true but whats grown on the equator won't do well in Siberia. Strains and conditions matter greatly.
Yes that's what makes me think there is no best humidity it's down to the individual plants, we can't look a vpd chart and then suit a Siberian strain and an equatorial strain for example there's one ideal figure.

Imo statements like "I like 50% over 60% the buds are denser is nonsense imo.
I'm not suggesting there's no difference in laboratory condition or professional set ups, but most of us have a tent with loads of variables every crop, how can anyone say humidity is thee positive or negative is beyond me.
 

Wizzlebiz

Well-Known Member
Yes that's what makes me think there is no best humidity it's down to the individual plants, we can't look a vpd chart and then suit a Siberian strain and an equatorial strain for example there's one ideal figure.

Imo statements like "I like 50% over 60% the buds are denser is nonsense imo.
I'm not suggesting there's no difference in laboratory condition or professional set ups, but most of us have a tent with loads of variables every crop, how can anyone say humidity is thee positive or negative is beyond me.
That is very true. I grow strains like BC big bud due to its tolerance for high heat. Im sure there are strains that have genes that make them better in a low humidity environment or vice versa.

Thats a whole other monkey wreck thrown into the equations for sure.
 
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Humboldtcalikidd

Well-Known Member
I know humidity, dense fog, and early morning dew plays a big roll in my outdoor.Slowly evaporating before the morning sun hits them and fries the plant
 
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