LED grow lights... input please.

The really strange thing about plants absorbing only red and blue (purple when mixed), is that there is more yellow and green light out there! Now thatâ??s weird! Our eyes learned to be more sensitive to green and yellow, but plants didn't. Turns out they think that there were actually plants able to absorb all that green and yellow sun light out there, and it was a purple plant! Our plants are only green because red and blue was the only useful light that came through the other plants for the ancestor of our plants (the ones we know and love) to absorb! Weird to think, if things had been different, the world leaders wouldnâ??t be as much concerned with converting to green energy as converting to purple energy.

Hey everyone

A friend and I have invested a bit of money on a grow op which includes the xb100 led starter system from GROW WITH LEDsâ?¢ - Growing Plants Using LED Lighting, stealth grow bubbleponics system, and some feminized white widow seeds from marijuana-seeds.nl. We're waiting on the seeds which should be here any day, but we checked out the lights today and they're awesome. I'll keep everyone posted on our results

I love stuff like this...new techniques, revolutionary developments. I look forward to reading everyone's experiences.

What would happen if you strobed the led's or used car neon tubes?

If LEDs for plants are successful at growing and flowering, they will revolutionize indoor gardening. And I can't wait...

The Eco Green Star Grow Bar has the most attractive overall package. They have information on color, power consumption, recommended growing areas per bar, and more at their website. Each bar is equivalent to 1 250 watt MH or HPS lamp.

Pricing is anywhere from $179 for 1 bar to $1,969.00 for 11 bars.

I would love to try these and stop worrying about ventilation for my cabinet.

Ive seen some of the led things folks have been putting together over the years and thought I could do better. This is a solid sheet of LED with 660 and 470nm lights the most powerful available in 5mm. I found some better blues at 430nm that are really bright and I should have used those instead. I thought of alot of improvements including a way to achieve 90% power efficiency from the wall socket and a way to adjust the power going into the red or blue lights if you want to 'change seasons.'

Theres just one point I dont think anyone has touched on here yet, is the efficiency of LEDs. They can be around 10-20% efficient, meaning 80-90% of the power you put in is turned into heat, and this is not much better than HPS. More power is wasted into heat as you convert AC to DC, and then even more when you regulate your DC to 20mA.

I heard some folks mention that the high-flux LEDs that require a heatsink are the only ones that work. It takes about 60 discrete 5mm LEDs to equal the luminous flux of 1 high power led. The thing is, 60 discrete LEDs are 1/5 the price of 1 high power LED and thats not including the heatsink. Additionally, high power LEDs have a much lower rated lifespan.

Anyway, let me know what you think. I have not tested it on a plant but I know it kicks the crap out of eco green star and ledgrowlights.com.

dude outerspace, that is the sweetest led set up i have ever seen. interested in selling one of those light boards? im working on a led/hps flower box (mostly leds and only 250 watt hps) i want to see if i can pull as much if not more than my 600 watt hps in the same enviroment :thumbsup:

let me know ya?

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Originally Posted by outerspace

Theres just one point I dont think anyone has touched on here yet, is the efficiency of LEDs. They can be around 10-20% efficient, meaning 80-90% of the power you put in is turned into heat, and this is not much better than HPS. More power is wasted into heat as you convert AC to DC, and then even more when you regulate your DC to 20mA.

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He's right. LEDs are way more efficient than incandescent bulbs, but they're not 100% efficient. Here's the chart:

Luminous efficacy - Wikipedia, the free encyclopedia

An HPS bulb has a luminous efficiency of 22%, while white LEDs have efficiencies from 3.8% to 10.2%, with only prototypes reaching up to 22%.
So, by using LED bulbs for growing, you are spending more money per bulb, and you are going to be spending more money on your electricity bill.

Sounds pretty stupid to me.

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Originally Posted by outerspace

I heard some folks mention that the high-flux LEDs that require a heatsink are the only ones that work. It takes about 60 discrete 5mm LEDs to equal the luminous flux of 1 high power led. The thing is, 60 discrete LEDs are 1/5 the price of 1 high power LED and thats not including the heatsink. Additionally, high power LEDs have a much lower rated lifespan.

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Good points all, but at this moment, ALL LEDs (high-output type which must be heat-sinked or not) are far too expensive, far too inefficient and don't produce near enough luminous output per LED device to be useful in a grow op.

The problem being that luminous output figures (lumens) added together are meaningless. Putting one light source next to another does not make either one any brighter. Lumens are a measure of perceived brightness, not a measure of photons being thrown at your leaves.

For example, if you have CFLs rated at 1300 lumens and you have 50 of them, you then have 50 light sources which are 1300 lumens 'bright,' not 50x 1300 lumens. Same goes for LEDs. The smaller, lower output LEDs, even if run in great numbers, will never be as bright as an LED with a higher luminous output.

Cannabis needs the brightness (or light intensity) to keep internodal lengths short and produce high-density buds. I have yet to see an LED grow that didn't show signs of serious light starvation.

LEDs are a terrific technology; the increases in output and reliability are coming by leaps and bounds in recent years... but it's not quite to the point where you can grow plants with them.

Mind you, I don't begrudge anyone the privilege of experimenting with new technologies. No one but us is likely to try the new stuff on cannabis.

However, if one is on a limited budget and just wants to grow some dope with little money or is a very new grower, spending up on re-inventing the wheel via experimental technologies probably isn't for you. Use what is proven to work well.

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Originally Posted by moeburn

He's right. LEDs are way more efficient than incandescent bulbs, but they're not 100% efficient. Here's the chart:

Luminous efficacy - Wikipedia, the free encyclopedia

An HPS bulb has a luminous efficiency of 22%, while white LEDs have efficiencies from 3.8% to 10.2%, with only prototypes reaching up to 22%.
So, by using LED bulbs for growing, you are spending more money per bulb, and you are going to be spending more money on your electricity bill.

Sounds pretty stupid to me.

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You're missing the one major advantage of LEDs here, that being that LED systems only output light on wavelengths that is ideal for plants to use. So even if a HPS system is 22% efficient, about 90% of that light is wasted because the plant can't use it, so really only 2.2% of that light is being used. An LED only puts out light one a single wavelengths, so with them, the numbers are reversed, and like 95% of the light being output is absorbed.

I found another site selling LED grow lights, this one looks a little more promising:

gro-tek.com

LEDs produce a very narrow spectral output; a bandwidth of only about 25nm wide for the most part. LEDs might be able to produce the centre-frequency of an ideal flowering spectrum and a few nm each way, but very little outside that narrow bandwidth, contributing to a completely insufficient luminous output overall.

Have a look at the broad spectral output of the sun (which is what we're shooting for), the narrower and peakier HPS (though which is reasonably well matched to the plant's flowering requirements) and then these sample red, blue and yellow LED spectral curves. Because of the narrow bandwidth of current technology LEDs, if you were replicating Old Sol or even HPS, several LEDs with slightly differing centre frequencies in each main color band would have to be used- and each would have to produce high luminous output, around 8-10K lumens each, to be of any effectiveness, even compared to CFLs.

If all that was needed to grow dope was light of the correct colour, you should reasonably be able to make up an image in Photoshop which is the correct colour and point your monitor at the plants... and I think we all know that won't work.

LEDs are a great technology. One of these days, someone will work out how to get the luminous ouput level and breadth of spectral output where they're needed. However, until then, LEDs are toys which won't actually grow you any appreciable amount of weed.

Experiment all you like- but by the time you get done sinking several hundred bucks into LEDs, you'd have had an HPS and a decent exhaust/ventilation system bought and paid for.

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Originally Posted by khronik

You're missing the one major advantage of LEDs here, that being that LED systems only output light on wavelengths that is ideal for plants to use.

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Unfortunately, plants don't live on just a couple of narrow peaks in the spectrum.

Yes, cannabis prefers a blue emphasised spectrum for veg and a red-orange spectrum for flowering- but notice I said spectrum, not wavelength.

When we say wavelength, we're referring to a pronounced, narrow bump in the spectral curve around a central frequency. 'Spectrum' refers to a broad band of different wavelengths between an upper and a lower limit, with light of relatively equal amplitude (intensity) between the points.

Back to first principles. You can bet that the plant has evolved to grow in sunlight. Whatever lighting system you cook up, the closer it is to Old Sol, the more likely cannabis will like to grow under it. The sun is a broadbanded light (and other EM radiation) source. Current tech LEDs are not.

We know HPS is broad enough and produces enough luminous output in suitable ranges to flower cannabis effectively (and is no slouch vegging, either). Fluoros are broad enough but lack intensity. LEDs lack both breadth of spectra and output intensity.

It's gonna happen- someone will soon cook up LEDs bright and broad enough to be car headlights. When that happens, LED grow lights effective for cannabis might start to become a practical possibility.

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Originally Posted by Al B. Fuct

Unfortunately, plants don't live on just a couple of narrow peaks in the spectrum.

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They can. If they couldn't, LED grow lights would not work at all. Just because I don't live on pop-tarts, beef jerky, and vitamin pills, doesn't mean I couldn't.

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Yes, cannabis prefers a blue emphasised spectrum for veg and a red-orange spectrum for flowering- but notice I said spectrum, not wavelength.

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Yes, chlorophyll can absorb a spectrum of light, but i doubt it can tell the difference between different shades of red. It can tell the difference between blue and red, but that seems to be all. And LED systems are set to use the wavelengths that are most readily absorbed in the blue and red spectrums.

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When we say wavelength, we're referring to a pronounced, narrow bump in the spectral curve around a central frequency. 'Spectrum' refers to a broad band of different wavelengths between an upper and a lower limit, with light of relatively equal amplitude (intensity) between the points.

Back to first principles. You can bet that the plant has evolved to grow in sunlight. Whatever lighting system you cook up, the closer it is to Old Sol, the more likely cannabis will like to grow under it. The sun is a broadbanded light (and other EM radiation) source. Current tech LEDs are not.

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This last part I take issue with. Does any indoor grower try to emulate the sun with their lighting system? No, they try and emulate the chlorophyll absorbsion spectrum. Plants, and all other living things, have evolved to survive in the natural environment, but that doesn't mean that environment is ideal for them. I for one, prefer my house to the african savannah.

I attached a nice graph of an LED grow light spectrum superimposed on the chlorophyll absorbsion spectrum.

OK, khronik, if LEDs work so well, you show me pix of an LED grow that's doing as well as an HPS op with all other conditions right.

They just don't make the luminous output needed- this is why LED grows look like they've been left in the dark, because in comparison to what the plant needs, that's ostensibly what it's getting.

You won't mind if I don't chug Jack Daniels by the case while I'm waiting for pix of those forearm sized colas, willya?

I'm all for new tech. LEDs will get there- but they are not there yet. Give it 5 years and we'll talk again.

Mind you, I'm not taking YOU to task- only LED grow lighting technology.

I think that using LED lights would work fine for growing pot. You just have to cover the absorption spectra of the plant. The only way, as far as I know, that the plant absorbs light energy is through chlorophyll a and b.

Looking at the absorption spectra chart Chlorophyll absorption spectrum It looks like there are peaks around 425, 460, 640, and 660 nanometers. LEDs are specified by their dominant wavelength...easy enough to select some that would work for that (or at least close to it...they only produce them at certain frequencies after all). As long as these peaks are covered, the plant will gather energy, probably not as much as from a full spectrum light, but the light that strikes the plant will be more efficiently turned into energy for the plant to use. HID lights do the same thing, but there are a lot of wasted frequencies emitted that the plant uses very inefficiently. Check out this link if you want to learn more than you ever cared to about light emission spectra: The Science of Color, the Emission Spectra of the Elements and Some Lamp Engineering Applications

Ok...so what about the brightness of LED lights as compared to HID lighting? It is true that most LED lights are not very bright (~.5 lumens each), but certain types are produced (do a search for superflux LEDs on ebay) that put out ~40 lumens each. Thats pretty good when you consider that an array of 50 puts out about the same as a 100W flourescent bulb (~2000 lumens). Yes, thats not nearly as much as, say a 400W HPS (~58000 lumens), but if heat and power consumption are a concern, then LEDs may be a viable option.

I built two little LED arrays out of the superflux LEDs I talked about and currently have a few seedlings underneath them. They are at least not dying! I'll upload some pictures soon. My aim is not really to have a large yeild necessarily, but to reduce heat and power consumption...and to try something cool. They were pretty cheap to build by the way...all it consists of is 2x $10 packs of LEDs, some perfboard (~$10), some reflectors and a DC supply (from an old computer....dedicated DC power supplies are pretty expensive) I jacked from work. It did take a while to wrap the wires however. Who knows...I haven't done a lot of growing and chances are I'll kill my plants without seeing how well my LEDs work!

This has gone on for a few years now and not one, bit of data.
Grams/watts/month. If It worked It would be used by NASA , they have more money than any pot grower. But they still use florsent pannel arrays.
O God I want it Fast, Cheap, and right now.
You want to know something funny a 30 year old ballast and new bulb, still is the proven way. Wow ballast older than most on this board O Well

To be fair, NASA is testing LED grow light technology.

The new digital ballasts are an improvement on magnetic ones though. :D

Just an update on my seedlings...they're alive and well under the LEDs, but not having grown too much I can't say how they're doing in comparison to HID lighting. They've stretched a bit till now they're pretty much touching the lights, but there's not enough heat put off by them to harm the plants it seems.

Soon I'm gonna hook up a wattmeter to my power supply and see how much power I'm actually drawing, but ideally it should just be about 3.2(Volts per LED)X.02(amps)X50(#of LEDs) = 3.2 watts!

Since its a ghetto rigged power supply, some is being wasted though a dummy load to trick the computer power supply into thinking there's a motherboard there.....so we'll see how wasteful these suckers are....

So, the seedlings should have grown now. What do the adults look like? Please?

I have seen LED's compared to HPS 400w, and they're almost identical.

Growing Marijuana with LED, Growshow

this is strictly a LED grow I find online....

Thanks for the link. Very interesting, but I don't undestand why the guy has the LEDs 3 feet from the plants. One advantage of LEDs is that you can put them right next to the plants, for much better growth. He's producing scraggly looking plants, but he is experimenting, and he is getting buds. He needs more LEDs and he needs to have them closer to the plants.

Bed Bath & Beyond Product

Anyone herd or used these befor?

or these

C. Crane 120V 35 LED Light Bulb

I don't know anything about that first one except that it looks terrible for weed farming. Is it even LED? Assuming the 2nd one is in the proper wavelength, then yes it will work well. You would probably need 20 or so to grow a plant, and 50 or 100 of those to come close to equalling the yield of 400 watt MH. Just a stab at it.

im not too sure but if you look at the base of the babies it appears that the beam itself is only just spredding out enough to cover the entire plant. its my opinion that the reason he has them so high is inorder to have his lights cast a beam wide enough to cover it all? and did u see the end result? the size of the buds was very small as was the total amount.

kids ive been watching this whole LED thing for a really long time and for whatever reason NO ONE is posting any math formulas (in relation to abount of useable light required - per ft squared) ) / nano meters (to determine which of hundreds of types of LEDS to use - even within the red and blue wavelengths / lens types (to determine the spred pattern so that lights may be hung at the proper height) what we need to do is CONTACT some of these LED vendors and invite them to either post their addys here and researching specs in thier literiture or post INFORMATION..... maybe even make it known to these vendors that those who comply with our requests will be the PRIMARY suppiliers to the DOZENS of comsumers that are willing to invest HUGE amounts updating our rooms from this very site???

this is somthing that has to be done because i dont know about everyone but i do know that electricity is killing me costing me an extra $250 - $300 a month not to mention how much is being wasted just to COOL a room because of the intense heat generated by HIDs. all i know is that if any of these manufactures were to put out info id read it and if some were conflicting then id read it all and average out the #s...this has gone long enough what we need are some hard facts

There are LED's that shine in a wider angle, thus allowing you to get them close to the plant. You could get them close to the plant with non wide angle LED's too, you would just have to use a more reasonable amount. This is extremely necessary as the intensity greatly decreases as you move them back.

I agree about getting some numbers down. LEDs for weed farming is such a new concept it hasn't been thoroughly studied and documented. Ziggy, wanna be the first? I wish I could but I just don't have the time, darn it. I got a few numbers, but not enough for a real grow.

I still am waiting to see an LED grow that produced buds of any significance. I have no doubt that a person could get some decent bud from LED lighting. In general people are going about it wrong, and they refuse to spend any money to boot. At this point the initial set up would be expensive as hell to get one plant to bud nicely, but it can be done. Due to the life expectancy and low power draw, very soon they will become viable. Perhaps even today.

LEDs are nice. Low heat, means less A/C bill. Plus they run very low power. So less electricty used. They save money and grow some sick plants because you can perfect the color spectrum to how the plant works.

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Originally Posted by SFGurrilla

LEDs are nice... They save money and grow some sick plants.

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You got any links or examples?

Cause I have yet to see any.

I am doing a plataform with aprox 500 leds after reading this post, 250 red and 250 blues, pics soon.

Awesome! Looking forward to seeing it. How many plants for the 500 LEDs? I'm thinking one, but my guess is that you are doing more. What nm red and blue?

I am constructing a movable device for my clones, i am just waiting my plant to be able to give me some, with 500 ultra bright leds, 50% red and 50% blue, this is because i can not put high heat inside my closet, my options were CFL or fluo tubes, and now i will prove some luck with the leds. If it does work, will be really, really nice for me, with no danger of starting a fire in my case (because my closet its too small) and i can go for some vacations out there lol

I will upload pics as soon as my device is taking form.

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Originally Posted by Opie Yutts

I still am waiting to see an LED grow that produced buds of any significance. I have no doubt that a person could get some decent bud from LED lighting. In general people are going about it wrong, and they refuse to spend any money to boot. At this point the initial set up would be expensive as hell to get one plant to bud nicely, but it can be done. Due to the life expectancy and low power draw, very soon they will become viable. Perhaps even today.

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Opie i represent a co-op here in calif whose soul purpose is to cultivate medicinal cannabis for really sick people. my clients have decided long ago to spend whatever it takes to get what we need. currently this is what were looking at .....

HID Hut - the makers of the LED UFO - The Brightest LED on the Planet

as you can all now see this is a very expensive product. the co-op is in the process of buying THOUSANDS of dollars of lights and whatever you can possible help us with would be deeply appreciated.

thank you

If your co-op has money to experiment, then I would say go ahead and get some of those UFO's. I've studied up on what's available today, and those are some of the best available at this time, if not the best. However, it would be experimental at this point, and I would quadruple the number of UFO's per area that they recommend. I would not deplete your entire lighting fund until you tried maybe one or two of those for an entire grow, budding as well. I keep saying that I have yet to see anything budded solely with LED's that produces anything worthwhile, and I have yet to be shown how I am wrong. They work OK for vegging, budding is a different can of worms.

Notice the info said it can be used as a supplement to CFL or HID. That's all I would recommend at this time, and your money would be much better spent on some CFLs that are the proper spectrum. If you want to steer away from HID because of heat/power draw, I would recommend studying up on the newer more efficient T-5 fluorescent lights. Of course there is nothing on the market that compares to the results you get with HPS during budding.

If you or your clients are willing to spend whatever it takes, and you are dead set on getting LEDs at this time, I would pay someone to make the proper LED arrays for you, or at least design them. People who manufacture LED lighting products at this time use maybe one nm (color) for blue and one for red. I'm guessing to be truly efficient, your going to want about 6 or 8 other colors, or varying degrees of red and blue, with the blue being the dominant color during veg and red being the dominant color during bud. Not just any blue and red, but the proper nm that corresponds to peak chlorophyll activity.

Good luck and let me know if you have more questions. I'm not an expert, but I have studied LED's.

I'm reading here since quite a while and this post made me sign up finally.

I'm looking into building a led light with high-power leds (I personally wouldn't go for a 5mm led system), being into electronics since, well, decades. So I can compare my findings to the products that arrived on the market lately. One of the lights is the mentioned UFO, the other known to me is the procyon 100 from howngrownlights. Both have 80-100W of power-dissipation, something I aimed at for my own system, which I see somewhere between a 250 and 400W HID system.

I will have to try myself. A site testing (not selling) both of them - along with other led systems - on vegetables is maybe everybody should have a look at, if considering using leds for grow.

I just bought two different led grow lights. Both using the same leds. One is the flat panel type with 225 mixed red/blue leds. And the other is the screw in bulb type with 168 mixed red/blue leds, 30 blue and 138 red.
I'll update later when they have arrived and been set up.
Blue LED light range - 430nm radiation peak athwart a 466nm emission range,
Red LED light range - 662nm radiation peak athwart a 680nm emission range,
http://img.photobucket.com/albums/v6...fd97_1_sbl.jpg
http://img.photobucket.com/albums/v6...225lite_up.jpg


I would like to get one of these as well so that I can stimulate flowering in specific parts of the plant while leaving the main lights on above.
http://img.photobucket.com/albums/v6...ffb1_1_sbl.jpg
This chart may or may not have already been posted but either way here it is again.
LED Grow Lights Gro-Tek GroTec HID Hydroponic light Fluorescent Growing Metal halide MH growing indoors indoors Ultraviolet Infrared light emitting diodes

Prepare to have the light very close to your plants, unlike the pictures for those 5mm led-lights show. Closer than CFL.

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Originally Posted by Opie Yutts

I still am waiting to see an LED grow that produced buds of any significance. I have no doubt that a person could get some decent bud from LED lighting. In general people are going about it wrong, and they refuse to spend any money to boot. At this point the initial set up would be expensive as hell to get one plant to bud nicely, but it can be done. Due to the life expectancy and low power draw, very soon they will become viable. Perhaps even today.

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posted below are photos and a grow diary. i dont know if this is what your wanting but it appears to be the most extensive work ive seen thus far - he observes that on his next LED proj he would req of the manuf hes working w to increase the amt of RED lights used to foster more flower development

we can do better than this kids if we all share what were doing and how its working as for me im ordering my 1st ste of OFO's this week and starting my 1st LED grow under thier currend BLUE matrix and will f/u by req that a more RED matrix be developed


Experiments with Hydroponics, Aeroponics, and LED Grow Lighting

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Originally Posted by Opie Yutts

Thanks for the link. Very interesting, but I don't undestand why the guy has the LEDs 3 feet from the plants. One advantage of LEDs is that you can put them right next to the plants, for much better growth. He's producing scraggly looking plants, but he is experimenting, and he is getting buds. He needs more LEDs and he needs to have them closer to the plants.

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Opie,
Check this guys grow...hes got them all over the place.....

Treetops:thumbsup:


http://boards.cannabis.com/indoor-gr...2-hps-led.html

Lowryder :wtf: (and, notice he combined a HPS with the LEDs) ... I'm with Opie on this one "show me a BIGASS marijuana plant grown under LEDs" :jointsmile: ... I don't think ya can show me that, without spending $100,000 on LED lights ... but, it is a very intriguing idea, regardless, I'm hoping for great results :smokin: