Old Strains - New LED Light!

[Chuckeye]

Damn those are looking sweeter by the day. Totally loving the color you got going on and as I’m learning, you are maintaining turgidity. As also evidenced by your lack of complaint about drooping leaves now. Lmao!

Yeah, no complaints At All

Wow. Looks like you got a rouge giant hybrid looking type something in the back middle. I’m guessing that one and the lower right hand plant are the two monsters.

The middle back one is a cross between Maui Wowie and OG Kush, both of which are guesstimated to be 4 feet high plants...

The lower right is the Acapulco Gold, a cross between Central American Genetics x a Mexican Sativa ! This one can be a five footer

Cheers

 

[KeithLemon]

Beautiful.

 

[Sativa1970]

Mowi is one of my favorite strains that I make sure to never run out of. Love the creative energetic mood. I flip mine at 18 to 24 inches tall and wide to keep her bellow 5 foot tall and wide. Wait too long and sativas will take over a room. When they say it is only so big, that's usually more of a minimum, than the maximum size.

 

[Gee64]

Looking good Chuck!

 

[Gee64]

I understand pressure gradients, what and how VPD works. All plant bio chemistry functions on pressure gradients. My question was why is it, that the charts and calculators, have so much variation, from one to another. I know that there are different charts for different stages of growth. Plugging the same temp, RH and stage into several calculators or charts tends to yield different results. Calculators do seem to be far less accurate. This is just the first chart from a google search result. Notice they don't exactly match. 75F 60RH is a perfect VPD 1 on your veg chart but that would be a 1.19 on this chart. Perfect for late flower. Good science is repeatable. Why isn't this repeating?

All caught up Chuck. They are looking great! The uppotting really made them happy.

Not to keep beating the VPD subject, but it is both powerful and dangerous if not applied correctly. This chart posted by @Sativa1970 isn't a plant VPD chart, it's a room VPD chart. 2 very different things.

@Chuckeye you mentioned

Ah, so you can factor leaf temperature IN place of ambient !

Thay may explain the differences in charts...

But I am not buying another gadget

Cheers

You don't insert leaf temp in place of ambient, you need a calculator that has 3 inputs. Room temp, leaf temp, and RH.

I use this one.

I got it from the Google Play Store.

If you have a VPD meter such as the Pulse meter you can't just assign something like a 2 degree offset into the settings and leave it that way.

You need to make note of your current room temp, then use an IR gun to get leaf temp, then adjust the offset variable in the meter setup EVERY time you want an accurate reading.

Those meters kill or greatly damage a lot of crops because of this. If your using one and your plants are constantly starving and crashing this is likely why.

If VPD gets too high you pull water thru the plant faster than nutes can enter with the water intake at the roots, and starvation/deficiencies are guaranteed.

If it goes in the other direction the plants will constantly look fat and too wet, and bugs are on their way.

I don't enter my tent without an IR thermometer in my hand.

Other than keeping temp offset updated, the time of day is the other really important thing to remember.

You can check accurate VPD any time of day you like (accurate=proper leaf temp offset) but only make adjustments based on the reading you take at 10 hours after lights on. If you make adjustments at earlier times then again, your plants will suffer.

VPD is also a very excellent way to dial your light in, far more accurate than a light meter, but thats a whole other rabbit hole.

 

[Sativa1970]

@Gee64 So you are saying that the puls chart is using room RH and leaf temp where the chart I pulled up is using room RH and room temp? Didn't catch the room VPD because it was just the first result on a google search. That would explain why the calculators that use 3 variables never quite match the charts that only use 2 variables. Two charts using a different temp variable wouldn't match each other.

Never actually checked, but I just assumed, leaf temp would be near ambient under LED. I just put that into the HID and greenhouse variable. You are right. Even the subtle difference of LED light would skew the chart. Happened to set a meter at canopy height yesterday for a different test and it is currently 3 deg hotter than the room.

 

[Jon]

Yeah, no complaints At All


The middle back one is a cross between Maui Wowie and OG Kush, both of which are guesstimated to be 4 feet high plants...

The lower right is the Acapulco Gold, a cross between Central American Genetics x a Mexican Sativa ! This one can be a five footer

Cheers

Awesome. Thanks.

 

[Chuckeye]

Mowi is one of my favorite strains that I make sure to never run out of. Love the creative energetic mood.

So looking forward to trying it

Do the munchies come with it ? That is the box I Need to tick

I've got a half dozen strains that do everything else, he, he...

I flip mine at 18 to 24 inches tall and wide to keep her bellow 5 foot tall and wide. Wait too long and sativas will take over a room.

My SOP has always been to flip at around day 50 and with topping/training they are around 18" tall. Still, I've had runts that I ended up super cropping at 5'

When they say it is only so big, that's usually more of a minimum, than the maximum size.

I've always taken that as a ball part figure and go ahead and grow the strains I'm interested in anyway

Cheers

 

[Chuckeye]

All caught up Chuck. They are looking great! The uppotting really made them happy.

Not to keep beating the VPD subject, but it is both powerful and dangerous if not applied correctly. This chart posted by @Sativa1970 isn't a plant VPD chart, it's a room VPD chart. 2 very different things.

@Chuckeye you mentioned

You don't insert leaf temp in place of ambient, you need a calculator that has 3 inputs. Room temp, leaf temp, and RH.

I use this one.

I got it from the Google Play Store.

If you have a VPD meter such as the Pulse meter you can't just assign something like a 2 degree offset into the settings and leave it that way.

You need to make note of your current room temp, then use an IR gun to get leaf temp, then adjust the offset variable in the meter setup EVERY time you want an accurate reading.

Those meters kill or greatly damage a lot of crops because of this. If your using one and your plants are constantly starving and crashing this is likely why.

If VPD gets too high you pull water thru the plant faster than nutes can enter with the water intake at the roots, and starvation/deficiencies are guaranteed.

If it goes in the other direction the plants will constantly look fat and too wet, and bugs are on their way.

I don't enter my tent without an IR thermometer in my hand.

Other than keeping temp offset updated, the time of day is the other really important thing to remember.

You can check accurate VPD any time of day you like (accurate=proper leaf temp offset) but only make adjustments based on the reading you take at 10 hours after lights on. If you make adjustments at earlier times then again, your plants will suffer.

VPD is also a very excellent way to dial your light in, far more accurate than a light meter, but thats a whole other rabbit hole.

As I mentioned I have limited control over my environment.

Right now I can keep the heat under 80 and the rh at ~50% with my exhaust fan only running for short periods.

Lights are at 50%/28", ~450 par/30,000 lux. Seems to be a good medium for the largest and smallest !

Just a hint of tacoing on the tallest, the Maui Wowie !

Even so, knowledge is Power (thanks for that) and I'm moving on to training

Cheers

 

[Sativa1970]

Mowi isn't really a munchy high. I get hyper focused on a creative project, or take a walk in the woods without stopping to eat. After smoking Jack Herer it might get ugly if you stand between me and a chocolate twinkie. lol

 

[Chuckeye]

Mowi isn't really a munchy high. I get hyper focused on a creative project, or take a walk in the woods without stopping to eat. After smoking Jack Herer it might get ugly if you stand between me and a chocolate twinkie. lol

LOL, Jack is On my list now

Cheers

 

[Fenderbender]

Jack should be a good one, back in the day that was the strain that knocked me on my feet.

 

[Delps8]

You need to make note of your current room temp, then use an IR gun to get leaf temp, then adjust the offset variable in the meter setup EVERY time you want an accurate reading.

There's simply no reason to take leaf temperature offset every time you want to take a reading. The offset very, very rarely changes and the only time it's not been -2° in three years of using VPD is that, for my last grow, I added fans to get to 2 meters/second of wind speed and that too my offset to -4.

Other than that signficant change in windspeed, it's been -2° since 2021.

You're injecting a lot of fear in what you write and VPD isn't the bad guy. Remember, VPD is just one number to describe temperature + RH. It's not magic. It's pretty much the same as saying 25°C is too cold but 68°F is just right.

Those meters kill or greatly damage a lot of crops because of this. If your using one and your plants are constantly starving and crashing this is likely why.

The meter doesn't have anything to do with it. "Attack of the Killer Thermometer" — does that make any sense?

If plants are "constantly starving and crashing" (whatever that means) it's because temperature and/or RH are swinging out of control. The meter has nothing to do with it.

Other than keeping temp offset updated, the time of day is the other really important thing to remember.

You can check accurate VPD any time of day you like (accurate=proper leaf temp offset) but only make adjustments based on the reading you take at 10 hours after lights on. If you make adjustments at earlier times then again, your plants will suffer.

That's absolute bunk. VPD is nothing more than one number instead of two numbers. If a grower decides to change nutrient strength when VPD is very high, there's simply no reason to wait a magical number of hours "after the lights go on".

VPD is also a very excellent way to dial your light in, far more accurate than a light meter, but thats a whole other rabbit hole.

Again, no basis in reality.

VPD impacts transpiration which impacts, in turn, water uptake. Light impacts photosynthesis.

The idea that you can "dial your lights in" (whatever that means) using VPD is nonsense.

 

[Chuckeye]

Come on @Gee64 and @Delps8, let's play nice

I'm grateful for all of the information freely offered !

What I take away from this conversation is a better understanding of the dynamics involved with the ideal environment for our favorite plant

I'm off now to chop the heck out of my Maui Wowie

Cheers

 

[budnoob3]

Mowi isn't really a munchy high. I get hyper focused on a creative project, or take a walk in the woods without stopping to eat. After smoking Jack Herer it might get ugly if you stand between me and a chocolate twinkie. lol

And then there’s chocolate OG that makes me chilly and completely unable to speak coherently for at least an hour. Yes, I love it but only in a 4 times a year kind of love akin to makeup relations

 

[Gee64]

Come on @Gee64 and @Delps8, let's play nice

I'm grateful for all of the information freely offered !

What I take away from this conversation is a better understanding of the dynamics involved with the ideal environment of our favorite plant

I'm off now to chop the heck out of my Maui Wowie

Cheers

lol I wasn't about to play unnice. I'm good. I didn't want you to give VPD a whirl without knowing the pitfalls is all, but your not using it so it's all good. .

Your pretty darn good at reading plants, you don't need VPD.

 

[budnoob3]

As for the VPD stuff, it peaks my interest and I enjoy learning new things; but I treat it as one of those things I’ve gotten by without knowing of it for a long time so I’m not going to kill myself learning all I can like a Netflix binge but I’ll definitely gradually take it in and try to leverage any new knowledge just can gain as an opportunity to improve going forward. Pretty much my attitude about anything

 

[Chuckeye]

Day 23

Well, it wasn't as difficult as I thought it would be

I just kind of Hate to remove perfectly healthy stuff, he, he..

So I kept the goal in mind and once Lambs Bread and I got cutting I had to slow down when I lost count of where I was, he, he...

It worked out to be my original plan !

Wait for the sixth node. Top there with a good inch of stem left and leave two nodes in total

And she is now at 8" high, go figure, eh ? Tomorrow I'll top off the medium !

I'll take this as a win

Before

After

The Girls before

The Girls after

There was still a bit of water in the reservoirs of the SIP's after 5 days so I will wait for tomorrow to give them another half gallon.

The coco/bags felt like about half weight so I gave them both a half gallon, just a bit of run off !

BTW > with HID I would be post transplant by two days, let alone starting my topping/ training

Cheers

 

[Chuckeye]

lol I wasn't about to play unnice. I'm good.

You Are

I didn't want you to give VPD a whirl without knowing the pitfalls is all, but your not using it so it's all good. .

Not quite accurate, I do what I can with limited resources, now I just look a little closer with an added understanding

Your pretty darn good at reading plants, you don't need VPD.

Thank you !

Cheers

 

[Chuckeye]

Last grow under HID at day 14 -25

Cheers