lighting Trying to understand LED Grow lights.

For those of you who know me, I moved from Fluorescents to LED grow lights this season.
Search as I may, the answers for growing pepper seedlings under LEDs is not so easy to find.

The seedlings were started with the lights down to 14" above the coco coir pellet's & set to 50 percent output.
So now that the peppers & others are in their 3.25" pots I need more space.

The higher you raise the lights the wider the light footprint, & today I lowered the plant bench 10 inches
it's now 24". I waited today to find answers first, before & lower or turn the lights up some.


Can I turn the light intensity up now that the lights are higher?

My grow space is 4' x 2' & I need every bit of that space to have enough light.
What is the perfect height & intensity output setting for my peppers now?

Fluorescent was so easy, you lower the lights right down to about 2 inches above the plants & turn the light up to 100 percent output.

These LED lights have the ability to fry my plants if I don't make the correct settings from the start.
Any help you can offer will be greatly appreciated.

Lights: https://www.viparspectra.com/products/xs-series-xs1500
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It's best to gradually lower them until you notice they're too close (seedlings will react accordingly). As the plants grow they will endure higher light output, so you may be able to adjust the height & intensity of the lights if needed. It also depends of the lamp. I usually keep my Mars Hydro T600 (non dimmable) about 4 feet above the plants while my homemade LED light hangs no more than 2 1/2-3 feet above the plant canopy.
 
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I'd do it like Bou says; start high and adjust according. My LED's aren't adjustable and would fry a sprout in a hurry if they were too low.

I have a few of these, which pull about 119 watts from the wall. I start out my plants under T5HO's, which I prefer for the young plants, then migrate them to the LED's once they're bigger. I keep one LED per 4x2 table and it covers that footprint pretty well at perhaps 24" above the plants directly under the light. I use the very outer edges of the table for varieties that like less intense light or sometime rotate plants from the outside to inside, but pretty much all the table space will grow peppers just fine. With two lights in what looks like a 4x2 tent you should have ample coverage, and could likely go lower than I do with reduced intensity and still have superior coverage.
 
My LED's aren't adjustable and would fry a sprout in a hurry if they were too low.

The only thing I found about growing peppers under this Viparspectra XS 1500 was to put them at 14" above & 50 percent power.
I have watched videos about growing pot with lights at the top of the tent set to 100 percent, growing weeds in the soil below the plants.

The problem with adjustable intensity is there are no set height to power charts.
Like at 14" set lights at 50 percent. At 24" set light to 65 percent ???

I can see the 24" height covers more grow space than 14" does however the light intensity is visibly less strong on the plants.
So is it a good idea to keep the light at 24" & set the power to 60 percent?

If you can grow weeds under a mature weed plant, thats a lot of light.
 
I'm converting all the inches in this thread to centimeters and I'm starting to think I might put my seedlings to close to the lights. How do I calculate the distance from seedlings to my grow lights without adjustable intensity?
 
How do I calculate the distance from seedlings to my grow lights without adjustable intensity?
I did read to buy one of these. https://www.amazon.com/Apogee-Instr...uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl

Not gonna happen!
Not relying on my Telephone for anything but talking for 66 years I just learned about using your telephone to measure light intensity.
I should have known & it's free, I know LOL, however it has to be better than the back of my hand.

I'm going to leave the lights at 24"/60.96cm & turn the lights up to 60 percent & watch them like a hawk.
Before I do it may be good to take readings with my phone testing 50 percent at 14"/ 35.56cm & 60 percent at 24"/ 60.96cm using 60 percent.

As for how far above. https://www.spider-farmer.com/products/spider-farmer-sf600-led-grow-light/

All the ads I see for LEDs the lights are feet above the plants. I assume most are set at 100 percent.

The only time I ever worried about burning my plants before was when the growing tops grew into the Fluorescent bulbs.
I can see I'm on my own, the path is not clear at this time.
 
I'm converting all the inches in this thread to centimeters and I'm starting to think I might put my seedlings to close to the lights. How do I calculate the distance from seedlings to my grow lights without adjustable intensity?
That's what CD and I explained above; there is no need to fuss with this parameter! Simply start higher and lower your lamp a few inches each day until your plants show you've pushed it too far! Lamps are hard to compare from one to another (quality and number of leds vary a lot) and not every plants will show the same light tolerance, you need to find your own balance!
 
For those of you who know me, I moved from Fluorescents to LED grow lights this season.

Search as I may, the answers for growing pepper seedlings under LEDs is not so easy to find.



The seedlings were started with the lights down to 14" above the coco coir pellet's & set to 50 percent output.

So now that the peppers & others are in their 3.25" pots I need more space.



The higher you raise the lights the wider the light footprint, & today I lowered the plant bench 10 inches

it's now 24". I waited today to find answers first, before & lower or turn the lights up some.





Can I turn the light intensity up now that the lights are higher?



My grow space is 4' x 2' & I need every bit of that space to have enough light.

What is the perfect height & intensity output setting for my peppers now?



Fluorescent was so easy, you lower the lights right down to about 2 inches above the plants & turn the light up to 100 percent output.



These LED lights have the ability to fry my plants if I don't make the correct settings from the start.

Any help you can offer will be greatly appreciated.



Lights: https://www.viparspectra.com/products/xs-series-xs1500







 

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Unlike weed, pepper & tomato are "day neutral" plants so there is no such things as veg or bloom phases...
 
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Your right but the principle still exists as far as stage of plant growth. Veg applies to lateral growth. When it starts flowering adjust light height accordingly. Calm down big fella I can never take your place here. I respect you as a senior member but I will not dumb myself down to make others feel better.
 
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