The Gee Spot - You Finally Found It

[Gee64]

How long will it take the plant to adjust leaf temps; minutes, hours or days?

Minutes to hours. Quite quickly.

I just lowered the plant by 2" and figured I'd check it again before bedtime to see if further adjustments would be required if the effect will be seen by then. I have the cab open so it's not a perfect comparison to what it is when it's closed up, but it should give me a sense, at least.

Ok perfect. It's all a great start.

How so? I would think air temp is more a function of airflow and heat from the lights.

I was just thinking if your light is generating less light, as in turning it down, then maybe it would generate less heat too, but ventilation can certainly lower temps too. Anything you can do to bring your VPD down is good.

 

[Azimuth]

I was just thinking if your light is generating less light, as in turning it down, then maybe it would generate less heat too, but ventilation can certainly lower temps too. Anything you can do to bring your VPD down is good.

Oh, yeah, no. My lights are vanity lights like you'd see in a bathroom with screw in bulbs. The only way I can adjust the light intensity is raising or lowering the plants. So, limited variability but still some.

The bulbs are on 6" spacing so lowering the plants might actually increase usable light as well as lowering leaf temps.

 

[Gee64]

It got down to 2.9C last night and rain. Today the sun came out. It's too bad this pheno only has purple in her, but she is a pretty one. The purple came in a lot today.

 

[Gee64]

 

[Gee64]

Oh, yeah, no. My lights are vanity lights like you'd see in a bathroom with screw in bulbs. The only way I can adjust the light intensity is raising or lowering the plants. So, limited variability but still some.

Can't you just wire on a dimmer switch?

The bulbs are on 6" spacing so lowering the plants might actually increase usable light as well as lowering leaf temps.

This is totally possible. I see that in the veg tent when I have to raise the lights

 

[Azimuth]

Can't you just wire on a dimmer switch?

Both plants would have to be on the same intensity if I did. Each panel is 6 lights left to right, half over a plant in the first 6 weeks, the other half above a plant in the last 4-6.

This is totally possible. I see that in the veg tent when I have to raise the lights

I've taken the globes off so lose the diffusion effect in exchange for intensity, but also much less spread.

 

[Azimuth]

Ok, a couple of hours in and the leaf temp has dropped but is still 0.5° above ambient so I lowered the plant another 1.5".

It's definitely praying less but maybe if I can get it cranking it will be able to handle higher light intensity later. Ppfd is down to low to mid 800's.

 

[Gee64]

Ok, a couple of hours in and the leaf temp has dropped but is still 0.5° above ambient so I lowered the plant another 1.5".

It's definitely praying less but maybe if I can get it cranking it will be able to handle higher light intensity later. Ppfd is down to low to mid 800's.

Remember, the point isn't to drive light higher, the point is to match light intensity to the rootball and the environment.

If that settles at 700ppfd, then you need to fix your roots and/or environment, and then when you crank up the light it will go to a higher ppfd before leaf temps get to high, so then you fix roots and environment some more, and crank up the lights to a 2 degree spread again.

Repeating almost forever.

You need to find the 2 degree spread 1st so transpiration works right, then you can fix the rest.

 

[Gee64]

See this pic Azi. The leaf petioles are at a nice praying angle, but the leaves themselves are almost droopy, rounding down-ish at the tips. Zoom in and look at the serrations. See how they are jagging up like there's lots of light? Thats because there is. 950ppfd. If I turned it to 1000 or 1050 or 1100 I could make that droop turn into a nice tight super pray, because those jags would pull so tight it would flex the leaf tip straight, and angle the leaf edges up.

The only problem with that is now my leaves would be cupped.

If you lower your light and your praying droops to about here, your fine

Praying is good but don't let them cup.