New grower here.

Something I’ve learned is that this is a hearty plant.

you probably just sent a clear message about who's in charge

Beefcurtins said:

Hey so I accidently left my infrared lights on for a total of two hours. A hour and a half of which being after the main lights are turned off. It slipped my mind as I was guna give them five more mins then I randomly remembered. Just glad I didn’t leave them on all night. I cannot find anything at all online in regards to issues with having to much infrared or to long. They are definitely visibly stressed by this and I need to know whether or not this was something serious they won’t be able to recover from or if they will be fine from now on.

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I have left mine on for 16 hours.
Don’t see any stress yet.

Why are you using infrared lighting? Curious that’s all.

Zill said:

Why are you using infrared lighting? Curious that’s all.

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Guessing there just the supplemental UV/IR bars, I have them as well but haven’t used them all grow, may turn them on the last 2 weeks to see if it makes any difference

Infrared radiation absorbed by anything will heat up. It has a wavelength longer than visible light, ~700 - 1,000nm. Many folks growing in doors complain about heat and removal of heat in the grow spaces, tents, etc..

Thats why I asked.

It will not harm them for such a little time, plus they are in veg so anything up to 24h works

Why illuminate plants with IR?

@GNick55 Can you post that lighting article again?

Found it, great read : https://stratcann.com/insight/growing-cannabis-debunking-the-light-leak-myth/

Here we go. I’m not trolling.

IR is not red light. Plants have no use for IR in photoperiodism, phytochromes or photosynthesis. The article talks red light. Red light is hugely important but nothing longer than 700nm. No effect.

Zill said:

Here we go. I’m not trolling.

IR is not red light. Plants have no use for IR in photoperiodism, phytochromes or photosynthesis. The article talks red light. Red light is hugely important but nothing longer than 700nm. No effect.

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gold

Johnny Man!

IR has no effect on photo marijuana plant??
hahaha yea ok Zill..
you even read all of the article?.,

Yup just did. IR is not red light.

Zill said:

Yup just did. IR is not red light.

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didn’t say it was, it was you who said ir light is useless to photo plants..

@Zill The Emerson Effect : Emerson effect is by using an infrared wavelength of above 700nm in order to accelerate the interaction of molecular energy.

JohnBlazr said:

@Zill The Emerson Effect : Emerson effect is by using an infrared wavelength of above 700nm in order to accelerate the interaction of molecular energy.

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Adhering to the McCree curve has led many to ignore indirect benefits of certain wavelengths of light, such as those longer than 700 nm. In 1957, Robert Emerson discovered that when plants were simultaneously exposed to both deep red (660nm) and far red (730nm) wavelengths, the rate of photosynthesis was far higher than the sum of the deep red and far red light separately. When used in synergy with deep red, far red light reduces the dissipation of absorbed light as heat, increasing photosynthesis rates.

For the sake of clarity, you should always name the specific wavelengths because plants do not have human eyes and do not perceive these wavelengths just as we do as abstract "red" "green" but they use several photoreceptors that can absorb a much broader spectrum although one -phytochrome- does have a breaking point at around 700nm, where red becomes farred and the light is no more PAR.
Plants can sense, and use, farred up to 780nm, very intricate lab tests have shown even a bit further down into IR, but real IR - talking heat radiation - that is wavelengths starting from 1000nm to way beyond 5000nm, this is what is usually been used in IR radiators etc.. these wavelengths do only heat up the leaves and are not sensed by phytochrome.
As for using FR "IR" at the end of the day, it's a "sleep" initiation, or better, it helps speed up the conversion of Pr to Pfr, which usually happens in the dark from alone but needs close to one hour. So to use a FR-EOD can help the accumulation of the hormones that trigger the flowering response, in other words, it's like the night had extra hour added, so instead doing 12/12 you can do 13h of light, followed by 15mins 730nm FR and just 11h of night. In order to pump more light in the plant, or you let it at 12h and just help it in case it mucks around, some genetics may indeed need more than 12h of night for the finish.
Now outside in nature the evening dawn there the spectrum is totally dominated by farred so this puts plants already "to sleep" this is why outside light pollution or fullmoon light etc may not matter. In the end it's a matter of the ratio of PAR red : farred which is measured and weighted against and this creates a hormone state which will further dicate how the plant is going to react to the ambient light scenario. So it's possible if the plant in sleep is illuminated with adequately strong light all the Pfr will transform and "awaken" the plant, then reveg or delay of the flowering transition can indeed occur.
One last word, as the article above stated you can neutralize a night interruption with ending in FR - that only works for a few times, like 2-3 consecutive days, after that, the plant will behave as being PAR illuminated. It's because PAR light is sensed by other receptors as well. But that trick does e.g. work if an accidental night interruption happened during flower, then do FR-EOD and it will be much less chance of reveg. Also when having to work in the growspace at night using a green mono, the FR-EOD is helpful. But don't use FR excessively several times throughout the flowering night - it also can delay flowering then, Bugbee did a thorough test on this one with Cannabis as well.

Cheers