Light and Plants

Here's a nice lil read I found.

Thats some great info bro should put that as a sticky pretty interesting thanks gonna save that if ya dont mind gotta read it a few times before it sinks into my stoned brain

Move this back up for those who didn't see it.

Clearly, both lumens and lux (or foot-candles) refer specifically to human vision and not to the way plants see light.

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How then should the rating for plant lighting be accomplished? There are two basic approaches to develop this rating: measuring energy or counting photons.

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Quotes from the article.

Thanks, man! I missed it the first time around. Great info!

This right here explains why I've been having trouble with my LED grows:

In the same way fat provides the most efficient calories for humans, red light provides the most efficient food for plants. However, a plant illuminated only with red or orange light will fail to develop sufficient bulk. Leafy growth (vegetative growth) and bulk also require blue light. Many other complex processes are triggered by light required from different regions of the spectrum. The correct portion of the spectrum varies from species to species. However, the quantity of light needed for plant growth and health can be measured, assuming that all portions of the spectrum are adequately covered

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The LED manufacturers would have you believe you only need RED and BLUE. AND if you look at the graph included in the article, the plants do in fact use the ENTIRE visible spectrum (provided the article is correct).

thats neat man! awesome read! thanks

Looks like orange(looks like the best spec for plants imo), red, yellow, blue and violet could be substantial in led grows. I'm going to add some yellow, orange and violet to my set up and see how the plant reacts.

bombbudpuffa said:

Looks like orange(looks like the best spec for plants imo), red, yellow, blue and violet could be substantial in led grows. I'm going to add some yellow, orange and violet to my set up and see how the plant reacts.

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Right on man! I think the other colors might be more important during the flowering phase for those "complex processes." For vegging, I've found that having just red and blue work pretty well.

I think the other colors might be more important during the flowering phase

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If I can find them AB. Seems green, red, blue and yellow are pretty much all thats available. I'll keep looking and if I find somewhere that sales ALL color bulbs i'll post a link!

Thanks for the incredible information. Here is a link http://ledmuseum.home.att.net/spectra7.htm that contains the light spectra for absolutely every kind of fluorescent bulb imaginable:holysheep: , for those of you who light with fluorescents or CFL's.

Happy Happy Joy Joy,
Cam

Great find Cam...bookmarked!!!

Glad to be of assistance, I thought it was a pretty cool resource

bombbudpuffa said:

If I can find them AB. Seems green, red, blue and yellow are pretty much all thats available. I'll keep looking and if I find somewhere that sales ALL color bulbs i'll post a link!

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Here is a place that sells a mixture of colors including whites and UV and IR.

http://www.superbrightleds.com/leds.htm

Of course, you will have to build the arrays yourself....

Great link AB. You ever order from them?

bombbudpuffa said:

Great link AB. You ever order from them?

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Yup. I ordered a few of the different colored LEDs from this company. I was going to use them in my current LED grow to see if different colors had different effects. Unfortunately, I seemed to have misplaced them, so that will have to wait until next time.

Okay, thanks. I'm going to have to look into how to build my own array.

so im assuming this chart is for the entire grow as I didn't see anything specifically speaking of a particular phase or I over looked it.

This is for veg/flower both right? And it did mention differentials in plant species I thought or i might be getting my articles mixed up.

I am currently trying to do an LED flower room, but it seems I have more blue than I thought I'd get on my bulbs as well, similar situation to another poster above. But by design, I know you need a little blue, and more red spectrum lighting, but green is considered a blue level light, and amber/orange are red level lights, are they really ALL required?

Thinking of the color wheel... using PRIMARY colors, Red, Yellow, and Blue, shouldn't it fill the spectrum? When you combine those colors, you get the CMYK colors (cyan, magenta, yellow, key) which when combined form RGB (red, green, blue) spectrums... Eventually a massive mix of all colors results in WHITE. Which then takes us out of usable LED lighting, back towards a more CFL type lighting system, does it not?

I'm kind of concerned now that LED's while a good source of low-heat substitutes, might be much harder to dial in a proper color tone.

What colors are REALLY recommended for LED's?

RED, GREEN, BLUE, AMBER, white??

What ratio is more favorable?

Say, out of 6 bulbs, to make a good combo of premade bulb arrays?
3 reds
1 amber
1 green or blue
1 WHITE?

using PRIMARY colors, Red, Yellow, and Blue, shouldn't it fill the spectrum?

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The colors we see aren't really what a plant needs. A plant needs those numbers(nm). To me, but this is just from that chart, it looks like adding amber, yellow, green and violet could be beneficial. It's true the red spec is good at promoting flowers and the blue promotes strong, healthy veg but whta is never discussed is what effect the other specs had. This wasn't too important with hids because they give off a wider spec. With leds they give off a slimmer spec from the color spectrum so other specs should be considered. This is just my opinion though and anyone elses thoughts would be appreciated.

RED, GREEN, BLUE, AMBER, white

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I'm going to try red, blue, yellow, amber and violet(uv).

md.apothecary said:

What colors are REALLY recommended for LED's?

RED, GREEN, BLUE, AMBER, white??

What ratio is more favorable?

Say, out of 6 bulbs, to make a good combo of premade bulb arrays?
3 reds
1 amber
1 green or blue
1 WHITE?

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That is what I would like to know also. The LED grow light manufacturers would have you believe you only need red and blue, but after doing a couple of grows with LEDs, I can tell something is missing.

During the veg phase, the red and blue seem to work very nicely, but come flowering time, I think we need to cover more of the spectrum. I was thinking of adding a few white LEDs on my next try. I attached the spetral graph of the "Warm White" LED. I think adding this to the existing red and blue will fill in the gaps. There is a dip in the green wavelength (actually aqua), but they sell some LEDs that can fill in that gap.

As to the ratios of each color, much more testing is required to nail it down.

Looks like GREEN is the missing link in that white spectrum, so essentially, I am thinking the main colors are still

RED
GREEN (SUPPLEMENTARY BULB/FILLER)
BLUE
AMBER/ORANGE (SUPPLEMENTARY BULB/FILLER)
WARM WHITE