Leggy seedlings with led?

TCH

Well-Known Member
Are you doing 12/12 from seed to put them into flower as fast as possible? If so, drop the light as far as possible and continue. If not, switch the light to 18/6 or 20/4, drop the light down as far as the plants will allow and watch the legginess stop. Recommended lux, dli, par, etc... are just that. Recommended starting points. All plants are different and act accordingly. Drop the light until your plants turn away from it and then raise it back up a couple inches.

If you are married to the numbers that are recommended, you will keep turning away good advice from the folks that have done this a LOT.
 

PopAndSonGrows

Well-Known Member
Trying to save energy? Put em on 16 hrs light (8 hrs lights off) and put the seedling much closer to the light. You can get a free PAR meter app on your phone to dial in the light intensity
 

thisusernameisnottaken

Well-Known Member
Are you doing 12/12 from seed to put them into flower as fast as possible? If so, drop the light as far as possible and continue. If not, switch the light to 18/6 or 20/4, drop the light down as far as the plants will allow and watch the legginess stop. Recommended lux, dli, par, etc... are just that. Recommended starting points. All plants are different and act accordingly. Drop the light until your plants turn away from it and then raise it back up a couple inches.

If you are married to the numbers that are recommended, you will keep turning away good advice from the folks that have done this a LOT.
10~4

there ya go. 12 hours of dark . they are stretching to find the light.
Lowered to 14-15k lux?

it allsoo says 16-24h light
Yes you are right.

Trying to save energy? Put em on 16 hrs light (8 hrs lights off) and put the seedling much closer to the light. You can get a free PAR meter app on your phone to dial in the light intensity
12/12 for space mostly.
 

nxsov180db

Well-Known Member
Need more light. Switch it to 18 hours on if not longer. I always do 24. 10k lux is too little, seedlings need more light than a clone..
 

Prawn Connery

Well-Known Member
You just convert lux to whatever.



12/12 23-24c.
You need to know what the conversion factor is before you can convert anything, because different spectra will have different Lux readings for the same number of photons. Plants don't care about Lumens (Lux), they care about photons in the PAR range. Ie; Photosynthetic Active Radiation measured in PPFD (Photosynthetic Photon Flux Density).

The only seedlings you should be starting on 12/12 are extreme sativas indoors and they will stretch like a mother fucker anyway. Not only is your DLI (Daily Light Integral) down from the recommended 18-20 hours of light per veg cycle, your light is too weak or too far away and it is also 3000K, which means it doesn't have a lot of blue light to supress internodal length (cell contraction).

TLDR:
More light, more hours
 
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thisusernameisnottaken

Well-Known Member
12/12 from seed? Right on. Done that a few times, even with an auto. Have fun ;)
12/12 auto is that even possible?

Need more light. Switch it to 18 hours on if not longer. I always do 24. 10k lux is too little, seedlings need more light than a clone..
12/12 testing.

Lux changes with spectrum. Lux is based on Plants don't Lux

You need to know what the conversion factor is before you can convert anything, because different spectra will have different Lux readings for the same number of photons. Plants don't care about Lumens (Lux), they care about photons in the PAR range. Ie; Photosynthetic Active Radiation measured in PPFD (Photosynthetic Photon Flux Density).

The only seedlings you should be starting on 12/12 are extreme sativas indoors and they will stretch like a mother fucker anyway. Not only is your DLI (Daily Light Integral) down from the recommended 18-20 hours of light per veg cycle, your light is too weak or too far away and it is also 3000K, which means it doesn't have a lot of blue light to supress internodal length (cell contraction).

TLDR:
More light, more hours
I think It's 3500k I lowered the light to 17-20k lux.
 
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thisusernameisnottaken

Well-Known Member
You need to know what the conversion factor is before you can convert anything, because different spectra will have different Lux readings for the same number of photons. Plants don't care about Lumens (Lux), they care about photons in the PAR range. Ie; Photosynthetic Active Radiation measured in PPFD (Photosynthetic Photon Flux Density).

The only seedlings you should be starting on 12/12 are extreme sativas indoors and they will stretch like a mother fucker anyway. Not only is your DLI (Daily Light Integral) down from the recommended 18-20 hours of light per veg cycle, your light is too weak or too far away and it is also 3000K, which means it doesn't have a lot of blue light to supress internodal length (cell contraction).

TLDR:
More light, more hours
I switched to 16/8 and ppfd is 400-430 and dli is 20-25 is this enough? Lowered the light to ppfd 550 dli 32.
 
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thisusernameisnottaken

Well-Known Member
I would stll give them 20/4 or 18/6 at least. They are the two veg light cycles I run.
Update another failed grow, after 7-8 days I checked the seedlings and they had almost no roots? I also had gnats, so I trashed the whole grow so annoying. Also tried hempy bucket with hydroton and that was just a big failure, out of 10 grows I have failed atlest 8 the rest was meh.

 
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