How close to put LED to plants?

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Hey guys, I have a Vipar B2X4 600w (360w actual draw) LED and Il be starting my grow soon.

Im unsure of how far away to have it from the plants, if somebody could clue me in that would be great.

Thanks in advance guys!
 
Don't under estimate the new LED's I would still start with a good 12-18 inches start around 18" away to start but you could probably move it a bit closer after they adjust. They don't run as hot so there is the ability to keep the led lights closer to the canopy but break them in slowly. I still don't run mine any closer then 12" even tho it seems it could sit flush with the tops and still not burn em.
 
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Ok thanks man. When I start off my seedlings would 18 inches away be ok? And then gradually start moving them closer until they are 12 inches away?
 
Seedlings I personally never start under anything intense just due to stretch. I always use compact fluorescent lighting daylight spectrum 6500k and keep em right on top of plants so my seedlings don't get all lanky and floppy.
Edit: Like literally 1-2" away from seedling tops.
 
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I dont have that option due to cash flow problems, I thought many growers even start their seedlings under 600w HPS to avoid stretch so surely a 360w LED wouldnt harm them?
 
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Not necessarily...but to begin each stage(veg or flower) I would start at around the distances I said...that is where the lights were designed for and where coverage to intensity are at their best.

If they get closer to 15 by mid to end flower and you don't see any bad signs...then your fine.

But those basic guide lines are the best place to start based on todays output technology.
 
For veg you want 24"-30"
For flower you want it closer to 18"
Man honestly you can start seedling under hps, mh, cfl, leds light is light and seedling really don't need much to get going but I honestly do find a huge stretch starting beans under any lights that are intense and farther away then a few inches IMHO. Any light will get them off to the races I personally just hate floppy seedlings. Tooth picks or staws work to hold em up tho if need be.
 
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Man honestly you can start seedling under hps, mh, cfl, leds light is light and seedling really don't need much to get going but I honestly do find a huge stretch starting beans under any lights that are intense and farther away then a few inches IMHO. Any light will get them off to the races I personally just hate floppy seedlings. Tooth picks or staws work to hold em up tho if need be.
I know what you are saying...but that is with a different light(floro)...he was asking for where to hang his LED...so I answered with what will give the right intensity...the same intensity that your floro is giving off dick high off the plants(I have measured led's and floro's PAR). I pop my beans with a 9w cree led bulb...then transfer to more light when they need it...but if my veg room has space...then in with everything else's they go. But this is about irishboii and what he has/can/will do.
 
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I know what you are saying...but that is with a different light(floro)...he was asking for where to hang his LED...so I answered with what will give the right intensity...the same intensity that your floro is giving off dick high off the plants(I have measured led's and floro's PAR). I pop my beans with a 9w cree led bulb...then transfer to more light when they need it...but if my veg room has space...then in with everything else's they go. But this is about irishboii and what he has/can/will do.
Have you studied the PAR on 3w, 5w, and 9w chips? I currently have a 240w w/ 3w chips and hover about 12" from the canopy. I feel safe with the distance I'm using, but do intend on purchasing a light meter at some point. Thanks
 
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Well, you really need an expensive PAR meter, more expensive than the one growershouse has been using.

Anyway, my next Lumigrow Pro 325 grow will have the fixtures three feet above the buds. I have been burning the top eight inch layer of my plants using a 27 inch clearance. That clearance was OK for the previous generation Lumigrow (ES series). This is based on my experience of two grows, the first used both Pro and ES and the second grow used only the Pro. I've got four fixtures in a line, two feet apart--so there is the overlap to consider.
 
I'm extremely frustrated about some yellowing I can't seem to figure out, I have another post about it, will update photos today. I gave nutrients after determining they were in need after 3 weeks into flowering (they are in roots organic soil which is jampacked already) and a week later, still yellow some brown tips and curling. Perhaps some are not getting light, but I keep spreading it and making sure everything has attention. Anywhoooo here's a pic of my buds today, seeing some beautiful crystals.
 
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I dont have that option due to cash flow problems, I thought many growers even start their seedlings under 600w HPS to avoid stretch so surely a 360w LED wouldnt harm them?
yeah dont worry about your light, keep it higher up away from the babies, make sure you arent overheating them with UV. Keep them watered but not wet, try to reduce the difference between day and night temps to avoid your plant stretching upwards. it is often a consequence of temp fluctuations and so uneven turgor pressure that often leads our plants to reach up and get all lanky. You might also look at how plants see themselves and understand how and where they are. Plants measure ratios of light, full light and shade if you like. If the parts where the light measured is mostly in shade, then our plants will stretch to find good quality light. Once they are in this good light, they will stop :-) Good luck
we are talking here about vDiff (day night temps) and Pr to PfR light (Phytochromes are red- and far-red light-reversible photoreceptors for photomorphogenesis in plants.)
 
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In sequence when discussing good red light on plants it looks something like this:
Plants grow in the sun ---> more Red light ---> Red light hits Pr ---> Pr to Pfr (Autophoshorylation) Pr +Pi --> Pfr ---> Pins in the membrane are moved into the bottom of the plant with vesicles ---> Auxin flows through Pins ---> Plant decrease elongation rate ---> short shoot plant.

You might also note, when our plants become subject to herbivore attack, sequences can be altered, not always in ways we assume are harmful.

Also Plants grow in the sun ---> more Red light ---> red light hits Pr ---> Pr +Pi---> Pfr (autophosphorylated) ---> Pfr conformation ---> increased JA (Jasmonic Acid) when herbivore attack is induced ---> Increased JA+ JAZ ---> Increased transcription factor that transcribe the gene for EFNs ---> Increased EFNs ---> Increased nectar volume ---> Increased ants ---> Decrease herbivory due to increased protection by ants. mad hey? :-)
 
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yeah dont worry about your light, keep it higher up away from the babies, make sure you arent overheating them with UV. Keep them watered but not wet, try to reduce the difference between day and night temps to avoid your plant stretching upwards. it is often a consequence of temp fluctuations and so uneven turgor pressure that often leads our plants to reach up and get all lanky. You might also look at how plants see themselves and understand how and where they are. Plants measure ratios of light, full light and shade if you like. If the parts where the light measured is mostly in shade, then our plants will stretch to find good quality light. Once they are in this good light, they will stop :) Good luck
we are talking here about vDiff (day night temps) and Pr to PfR light (Phytochromes are red- and far-red light-reversible photoreceptors for photomorphogenesis in plants.)
I just purchased a Stansen G900 watt led grow light, before hand I had a 600 watt led that I kept about 16"-18" from the tops. What would be a nice height for the 900 watt led. The new one also has grow and flower switches.
 
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