Settle this please. temp needs for LED

[Gemtree]

Not trying to start shit but I've grown in low humidity/high temp for a decade and always have killer buds. Just started using quantum boards and they're growing fine in 30-40% humidity. I did bump up the room temp to 77 from 73 because I thought they seemed small but I'm thinking it's just the strain. Haven't grown enough under led to compare.

 

[BBQtoast]

That's a fallacy.

It's not a question of what works and what doesn't work, it's a question of what if most efficient.

As an example, you can get across a street by hopping on one leg. That reality doesn't somehow disprove that walking on two legs is a more efficient option.

It solves an argument where one grower says under 60 is bad and the other says look at my grow, wow, now how is it doing so well at 20.

A fallacy but shows the extent of one misjudgement by a grower and that humidity is not important in this case.

Fuck efficiency, both crossed the road that's the truth.

 

[PJ Diaz]

It solves an argument where one grower says under 60 is bad and the other says look at my grow, wow, now how is it doing so well at 20.

A fallacy but shows the extent of one misjudgement by a grower and that humidity is not important in this case.

Fuck efficiency, both crossed the road that's the truth.

No one's saying their grow is doing great at 20F.

Sure, both guys crossed the road, but the guy hopping likely got there slower, and possibly tripped and sprained an ankle. Maybe got hit by a car because he couldn't get out of the way fast enough. The guy who used two legs was able to run the fuck out of the way and not get hit.

You're argument is akin to saying that you can grow weed with a 20-watt cfl, so it's not worth using a 1000w HPS.

If you want to debate, use facts, instead of simply trying to poke holes.

 

[PJ Diaz]

Not trying to start shit but I've grown in low humidity/high temp for a decade and always have killer buds. Just started using quantum boards and they're growing fine in 30-40% humidity. I did bump up the room temp to 77 from 73 because I thought they seemed small but I'm thinking it's just the strain. Haven't grown enough under led to compare.

If I had the choice between growing in low humidity or high, I'd choose low every time.

 

[BBQtoast]

No one's saying their grow is doing great at 20F.

Sure, both guys crossed the road, but the guy hopping likely got there slower, and possibly tripped and sprained an ankle. Maybe got hit by a car because he couldn't get out of the way fast enough. The guy who used two legs was able to run the fuck out of the way and not get hit.

You're argument is akin to saying that you can grow weed with a 20-watt cfl, so it's not worth using a 1000w HPS.

If you want to debate, use facts, instead of simply trying to poke holes.

20% rh no 20f.

We watched a lot of bipedal and one legged people cross a road, efficiency became not the question when someone else came along and rumoured us that one legged people can't cross roads.

Both crossed the road, no one noticed a difference in any way in perfect environment with low humidity compared to a higher but not extreme humidity.

The most efficient humidity was only noticed by a scientist in a lab as we couldn't tell, how much more efficient a two legged pedestrian traverses a road over a less abled one leg was easier to deduce.

It's both fact and subjective but we can easily say broscience to those who think low humidity is bad unless we're all scientists in labs talking about very tiny differences like wether a car came along or if crutches gave the one leg guy a speed advantage.

 

[Nwtexan]

As someone that isn't super educated in these areas, but likes learning about stuff, it's interesting to try to figure out what is right, and where to point the compass. I think because of the legality, there hasn't been as much research and then folks have come up with their own methodologies that work well for them, passing these along with mostly good intentions. I see the same thing in the organic world and the light world.

I guess part of it is learning to discern from the great "internet library" what will serve your purpose. In my case, I really enjoy the process, so much of my pursuit is towards gathering knowledge, and the end product is a bonus. For those who have more invested in it, I could see why it would be such a passionate issue.

I appreciate everyone sharing info, especially those that do it with a kind heart. We are all experts at some things and beginners at others.

Dig it.

 

[PJ Diaz]

20% rh no 20f.

We watched a lot of bipedal and one legged people cross a road, efficiency became not the question when someone else came along and rumoured us that one legged people can't cross roads.

Both crossed the road, no one noticed a difference in any way in perfect environment with low humidity compared to a higher but not extreme humidity.

The most efficient humidity was only noticed by a scientist in a lab as we couldn't tell, how much more efficient a two legged pedestrian traverses a road over a less abled one leg was easier to deduce.

It's both fact and subjective but we can easily say broscience to those who think low humidity is bad unless we're all scientists in labs talking about very tiny differences like wether a car came along or if crutches gave the one leg guy a speed advantage.

Growers such as Josh Neulinger who follow very careful and close attention to crop steering, have shown us over time that it's not bro science..



In fact, his approach is quite scientific..

 

[Kassiopeija]

What is the stupidity level for someone convinced they need high relative humidity to ignore everyone at low humidity producing exactly the same?

So the answer to whether LEDs need higher temperatures isn't yes, it's no you just haven't mastered what those at lower temperatures are doing and twisting shit to suit your own personal opinion.

This seems about right for a lot of what's debated here, let's find a little paragraph about calcium, let's link that to a light spectrum and then promote that LEDs need more calcium in the fertilizer. It's wholly untrue but I can present evidence some idiot will swear is scientific.

LED demands more Ca???? How did you figure that out? I thought it was Mg....? Is there really Ca in epsom salts? Guess more PAR = more nutes in general...

20% rh no 20f.

We watched a lot of bipedal and one legged people cross a road, efficiency became not the question when someone else came along and rumoured us that one legged people can't cross roads.

Both crossed the road, no one noticed a difference in any way in perfect environment with low humidity compared to a higher but not extreme humidity.

The most efficient humidity was only noticed by a scientist in a lab as we couldn't tell, how much more efficient a two legged pedestrian traverses a road over a less abled one leg was easier to deduce.

It's both fact and subjective but we can easily say broscience to those who think low humidity is bad unless we're all scientists in labs talking about very tiny differences like wether a car came along or if crutches gave the one leg guy a speed advantage.

so what is VPD for you? just stoner science.

you are really hard pressed for arguments. day is night and black is white....

 

[twentyeight.threefive]

Growers such as Josh Neulinger who follow very careful and close attention to crop steering, have shown us over time that it's not bro science..

View attachment 4799700

In fact, his approach is quite scientific..

View attachment 4799701

Fake news.

 

[Star Dog]

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.

 

[Kassiopeija]

Who's testested 40% against 45%% against 50% and so on?

VPD: Ideal temperature/relative humidity

So you thought your lights were too hot ... maybe you just need a bigger humidifier :woohoo: Here is a great post by @Kcar: Here is a simpler explanation Humidity and Vapour Pressure Deficit (VPD) For years Relative Humidity (RH) has been used as a measure of how much water vapour is...

www.icmag.com

 

[gwheels]

VPD for the win.

I got my bloom to 79.5F 50% RH and its right in the zone. The girls drink less, they drink the right amount.

the dehuey barely comes on (Huge savings in power....and the water you watered your plants with that ends up in the dehuey).

I did it by balancing the light power over the space because i am limited to a single 6 inch outside extraction.

I found the girls like the lights turned down to just under 80 better than when i run them hard at 83

a lot better.

I use a 1000HPS
1000 watts of boards
700 watts of cobs.

 

[twentyeight.threefive]

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.

Good point. I'm sure no one in history has ever done studies on it. VPD charts were probably just made up numbers stuck on a chart.

 

[twentyeight.threefive]

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.

Good point. I'm sure no one in history has ever done studies on it. VPD charts were probably just made up numbers stuck on a chart.

 

[BBQtoast]

LED demands more Ca???? How did you figure that out? I thought it was Mg....? Is there really Ca in epsom salts? Guess more PAR = more nutes in general...


so what is VPD for you? just stoner science.

you are really hard pressed for arguments. day is night and black is white....

I was taking the piss out of those who think LEDs need more calcium.

VPD is not a chart that plots temp against humidity, once you put in leaf boundary layer humidity does not swing the chart much. This also is visually apparent when you compare clones from 30% and 50%.

There is a difference we just can't see it, does 60% humidity yeild more than 40%? Think you get the point.

 

[BBQtoast]

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.

I've tested every humidity and every boundary layer. Within reason I couldn't replicate under 20%.

In still air humidity really changes plant growth, with air flow it doesn't have much effect.

There's an easier experiment, still air at 70% Vs air flow at 70%, eye opener!

 

[twentyeight.threefive]

VPD is not a chart that plots temp against humidity

So what exactly are the values for the x and y axes?

 

[BBQtoast]

View attachment 4799980

So what exactly are the values for the x and y axes?

That's not a VPD chart, that's the power of humidity against temperature.

Apply that chart to a leaf in 0.5m/s air flow and it doesn't work because you never put the z axes in for the power the humid layer around the leaf.

If you want to plot pressure put in all the resistances not just humidity. It's normally done by a computer in real time in a greenhouse and involves soil water measurements and other leaf measurements.

 

[twentyeight.threefive]

That's not a VPD chart, that's the power of humidity against temperature.

Apply that chart to a leaf in 0.5m/s air flow and it doesn't work because you never put the z axes in for the power the humid layer around the leaf.

If you want to plot pressure put in all the resistances not just humidity. It's normally done by a computer in real time in a greenhouse and involves soil water measurements and other leaf measurements.

It's exactly a VPD chart...

 

[BBQtoast]

It's exactly a VPD chart...

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.