Starting seeds in soil for the first time, LED lighting q's

Hi, this is my third indoor start for what will eventually be outdoor plants, but my first time using LED lights. I used fluorescents before but wanted to upgrade.

I have a small setup—Good Earth 2ft adustable full specturl LED, 31 watts with spectrum changing push buttons (blue, white, red). I’m growing Jack Herer and LSD autoflower seeds, put em in the soil today. They’re in Fox Farm Light Warrior seed starter in top half of solo cups, Coast of Maine in bottom half per some instructions I found in the forums.

Main q’s:
How far away should the lights be?
How many hours per day to get the seeds to pop?
Blue light only for now? Or a combo? And when to switch to white light/vegetative?

Thanks in advance!

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Hi hows it goin, use the light on full all beams on.
Distance is a result of “brightness” or ppfd as the plant sees it, a few hundred, 250 maybe.
Light schedule wont affect seeds pop, but soon as theyre above dirt I’d do 18h light 6h dark 'cuz it’s old and still popularly used.
Are they going in-ground or in containers outdoor

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Sorry, what distance should they be then? I don’t understand what you mean by “a few hundred, 250 maybe.”

They’re going to go in containers outdoors, eventually! :slight_smile:

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@dbrn32 is the light guru in these parts, gonna tag in him. Happy growing :call_me_hand:t2:

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Hi thats what light output is measured with.
Brightness to our eyes is lumens, to a plant its Photosynthetic Photon Flux Density. How many million photons per square foot.
A ppfd of 250 or 300 is often used with seedlings. An adult can take more like nearly 1000.
It might say on the packaging.
Some light-makers tell what distance gets that range.
Photone is an app for phones and devices that measures light.
With a light that like that I would use my hand to see how close I can get under it, to almost feeling the heat of it, then back off a couple inches. Watch the plants, post pics, ask, the couple days it takes to learn your light wont break your grow.

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Not sure about light this small. I’m guessing 31 watts is with all colors on? I’d say probably about 12" give or take.

Seeds will sprout without any light at all, but the heat from having lights on will usually help this along.

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