Will a green light disturb flowering plants?

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Dirte Bag

Dirte Bag

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Not so sure about white/yellow lights covered with green plastic though.

Well, the way I see it (pun intended), green is green. If you see correctly, that is if you are not colorblind, and something looks green, then it is indeed green. I would ask you what other method of determining color wavelength does one normally have on hand? A green LED is just green plastic.
 
Homesteader

Homesteader

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Not all green LEDs use filters to achieve their color. A single color LED can match a wavelength down to the single nano-meter after initial startup. Not sure how much flux you would get with a white light and a green filter (probably well within range)..... The point is it doesn't matter how your eyes see it, it depends if the receptors in the leaves detect red light. With a single color LED, 520-540nm is the only light produced so there is no question. This just may be the reason some people have had herm issues while using green lights (maybe not though).
 
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K

Ky420

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Just download an app from the playstore. I use green hydroponics app and it just provides a bright green screen. Perfect for times I have to go in when the lights are off.
 
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Fearist

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Hi buddy just been reading post because I been using these green leds cos cheap low power and the wave length is a fairly pleasant light to spray etc , but I was wondering if a specific wavelength nm of green is less stressing coz green light does carry a herm risk , I’d like to minimise https://www.toolstation.com/sylvani...gpGhS9PCRLSELKAYfSXET_JnmY9mznpBoC4-oQAvD_BwE
I have heard that a green light will not effect the flowering cycle, and will let you work on your plants when the main lights are off. Is this true?

I still setting up my grow and I won't always be able to get to my plants on time, so if this is true it would be a good option for me.
 
UK420Show

UK420Show

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I grow in tents and I flood my grow room with green light for this reason light leaks are very common and pretty much impossible to avoid at times with tents getting tiered after use ect its a handy tool to flood your grow room with green light so if any light does get in it cannot harm them anyway. I mean Telos Lighting just created a ballast with a flashing green light to signify when the lights are off if it was not safe I doubt they would of done that lol
 
mikeross

mikeross

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I grow in tents and I flood my grow room with green light for this reason light leaks are very common and pretty much impossible to avoid at times with tents getting tiered after use ect its a handy tool to flood your grow room with green light so if any light does get in it cannot harm them anyway. I mean Telos Lighting just created a ballast with a flashing green light to signify when the lights are off if it was not safe I doubt they would of done that lol

That's interesting information regarding green light and light leaks... never heard that one before.

I just setup a new room with Gavita DE SL2 fixtures with the wide angles reflectors... the ballast has a small green led built into it. When lights are off and 15 lights in the room these small green LED cast a light green glow on the canopy.... very dim, but totally awesome feature.
 
UK420Show

UK420Show

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That's interesting information regarding green light and light leaks... never heard that one before.

I just setup a new room with Gavita DE SL2 fixtures with the wide angles reflectors... the ballast has a small green led built into it. When lights are off and 15 lights in the room these small green LED cast a light green glow on the canopy.... very dim, but totally awesome feature.
Yeah they be fine :) wish you yhe best of luck for your new space :)
 
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TeW33zy

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no light at all...yes green light will stress your plants out....it may do it more then less to others based on strain...



keep all your lights off during the dark period....that is...if u dont mind harvesting some bannanas with ur nugz
That's False and a lie. There's is no way in life can that happen, it defies the law of growth. Plants don't photosynthesis green light at all. Infact it hates it so much it reflects it which is why Cannabis plants are green. If Cannabis plants didn't reflect green that will defy the law of nature. Ain't no way a plant will hermie with greenlight. All co2 monitors all have green lights on them. All of them
 
tobh

tobh

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That's False and a lie. There's is no way in life can that happen, it defies the law of growth. Plants don't photosynthesis green light at all. Infact it hates it so much it reflects it which is why Cannabis plants are green. If Cannabis plants didn't reflect green that will defy the law of nature. Ain't no way a plant will hermie with greenlight. All co2 monitors all have green lights on them. All of them
Just gonna leave these here.


and literally thousands of other research articles freely available via a simple google search.

Next time before talking about something you obviously have absolutely no idea about, might at least do a little research before claiming just because a plant reflects a color in the visible light spectrum that it's harmless to the plant. Whatever color a manufacturer decides to use for their LEDs is on them, green just happens to be cheaper than others.
 
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FranJan

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"Moreover, Cope and Bugbee explored the importance of green light for plant growth and development and explained that green light permeates deeper into the plant, further than red and blue, and therefore provides additional photosynthesis beyond the red/blue top leaf saturation levels. In lettuce grow with pure green light, the plant grew albeit weakly, surprising since many thought green light to be not used in the past, but in combination with red and blue light, the RGB grown lettuce was the most vigorous and healthy among all different combinations of light at the same PPFD levels. They did highlight that this benefit of green light is species dependent, as some plants lack the photopigments and phytochemicals to deal with green light, whereas many do."

I remember people growing great plants with neutral LEDs, which are very heavy green.

My explanation about green light in a flowering room is pretty simple;
if it's putting out enough lumens/lux, or whatever radiometric metric unit you use, and you spend enough time in your flowering room during lights off with them on, there's a very good chance you are going to stress your plants, which may or may not respond in kind with nanners or re-vegging. And in all likelihood, different strains or even phenos are going to respond differently too. This is why you get people/bros saying different shit about green light and whether you can or can't. Most folks are using different brands or wattage of green lights and growing different strains. Low level green light over a short period of time should be safe, (the green light doesn't penetrate the plant deep enough for photosynthesis to be effective basically), but if you try to get real work done in your flowering room you're asking for it until you know better.

Works for me.
 
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TeW33zy

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Just gonna leave these here.


and literally thousands of other research articles freely available via a simple google search.

Next time before talking about something you obviously have absolutely no idea about, might at least do a little research before claiming just because a plant reflects a color in the visible light spectrum that it's harmless to the plant. Whatever color a manufacturer decides to use for their LEDs is on them, green just happens to be cheaper than others.
False, I have a Masters degree in Biosystems Engineering, Agricultural and I work as a Sr. Quality Biosystems Engineer for the top MED-Device in North America. To each his on, I won't argue. Reject knowledge I'll move on. A cannabis plant will not photosynthesis nor will it have positive phototropism for green light in 510 nanometer. Same for grass, it has a primary wavelength of 495–570 nm and will reflect it.
 
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Homesteader

Homesteader

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Green light is the least efficient for driving photsynthesis but still drives it.

"Sometimes one may hear that plants don’t use green light for photosynthesis, they reflect it. However, this is only partly true. While most plants reflect more green than any other in the visible spectrum, a relatively small percentage of green light is transmitted through or reflected by the leaves. The majority of green light is useful in photosynthesis."

 
Homesteader

Homesteader

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I would put duct tape over any green light you have in your room on equipment. You probably won't have any issues if you don't but IMO, the darker the better always.
 
Moe.Red

Moe.Red

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False, I have a Masters degree in Biosystems Engineering, Agricultural and I work as a Sr. Quality Biosystems Engineer for the top MED-Device in North America. To each his on, I won't argue. Reject knowledge I'll move on. A cannabis plant will not photosynthesis nor will it have positive phototropism for green light in 510 nanometer. Same for grass, it has a primary wavelength of 495–570 nm and will reflect it.
This is a logical fallacy called "Appeal to Authority"

If you reject peer reviewed studies on this as linked above you are the one that is "rejecting knowledge" as you accuse others of.

Based on what we know right now and studies that have been done by legitimate scientists who's background and CV are openly presented the results are that green light does drive photosynthesis at a deeper level in the plant tissue. If you want to refute that study, you will have to prove your authority by linking the peer reviewed studies you or others have done so we are discussing facts, not opinions.

Science is open to changes based on new data. Are you? I am if you can prove with data that something science believes is wrong. Strong statement and appeal to authority are not it.
 
N1ghtL1ght

N1ghtL1ght

Staff
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I have heard that a green light will not effect the flowering cycle, and will let you work on your plants when the main lights are off. Is this true?

I still setting up my grow and I won't always be able to get to my plants on time, so if this is true it would be a good option for me.
I know it's an old thread, but seems to have stayed alive over the years, so just wanna throw my 2c in it.

So the general advice of not interrupting the flower-cycle, of short-day photoperiodic plants (ie. Cannabis), is to have them into UNINTERRUPTED DARKNESS during lights out. There has been some recent research by Prof. Bugbee et al that showed that even IR wavelengths (those which are used for IR monitoring in night-vision cameras) can delay flowering:
Photons from NIR LEDs can delay flowering in short-day soybean and Cannabis: Implications for phytochrome activity

So it stands to reason that wavelengths inside PAR can also do this, or even way better. Now aside from photosynthesis plants possess photoreceptors which they use to sense the spectrum, weigh its relative strengths and answer to it via photomorphogenics or phototropism. The responsible receptors absorb mostly, and heavily, in the UV/blue and red/darkred region. There is a small gap within the green wavelengths, however just because there is very little or next to none absorbtion doesn't mean the plant won't react to it; and this has several reasons:
- Plant receptor chromophores are highly sensitive and only need about 1umol/m^2/s fluxstrength to react accordingly.
- Greenlight can cause a yellow, red or darkred fluorescence that then is absorbed by photoreceptors within the leaf, and since both of this happens right inside a leaf it may escape any notice from outside measuring equipment.
- Greenlight can still drive photosynthesis and this is accompanyied by several sideeffect such as stomatal opening, phototranspiration etc - which is something a plant may not be used to during a real nightphase.
- Research by Prof. Folta et al showed evidence of a specific greenlight-reaction of plants that could be interpreted by having a still unknown greenlight receptor at large (e.g. see: Green Light Stimulates Early Stem Elongation, Antagonizing Light-Mediated Growth Inhibition)
 
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Grower1974

Grower1974

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I usually have 3-4 different LED's inside my grow room/tent's for years. I can almost see enough to do a little work at night. Never had a hermie in over 5 years. The lights emit basically ZERO (under .25 PPFD) to the plants. Paranoia is a disease.
 
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