Can I veg photoperiod for 24/0?

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Aqua Man

Aqua Man

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Sure I don’t grow like a commercial grower at all either. We grow for our needs likes and space and environment. I am specifically talking about medium to large fully packed rooms. And old school commercial set up and grow style.

And yeah they max the light out for sure. I have seen top hat reflectors almost touching all across the canopy. Led or hid there is no room for more light.
But there is a difference in the light produced... by a fixture at the same wattage... and that can be a huge difference. We see this all the time where an HID will burn the leaves before bleaching because of the heat production.. where as an LED giving to many photons will bleach a plant because it can't keep up with photosynthetic rates
 
MIMedGrower

MIMedGrower

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I'm missing what your saying somehow... watts don't equal yield, not even close. Photons equal yield. If that were the case HID would absolutely murder LED.

By cram as much light as possible I'm not sure what you mean? Enough to indice photorespiration? Photosaturation?

And I absolutely agree with you a commercial grower could care less in most cases.

Photosaturation, photorespiration and light stress are all real factors we can't deny. I don't disagree that a 2 hr dark period may be enough hell maybe an hr for all I know. What I'm getting at is not that it can't be done but that there are benefits to a dark period and many many growers report no significant difference in some reduction of photoperiod. I would explain that by saying the light intensity and the duration will equal the DLI (amount of photons delivered) needed to maximize growth.

So we can provide a more intense light for a shorter duration as long as photorespiration is not occurring and reducing the plants efficiency to convert it to energy


I did not see the negatives you keep bringing up. When the plants get “tired” they simply lower their leaves to reduce their footprint for a while then perk up and go again.

And Bruce said they don’t need a dark period I that video I am sure.
 
MIMedGrower

MIMedGrower

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No the less heat per watt is because it produces more photons per watt... therefore less energy is wasted producing heat. The more efficient a light uses a watt the less heat it produces as a byproduct.



when you cover the room in light with a par meter to achieve consistency and no low spots it doesn’t matter what type of light you use. The par is maxed out for growing purposes. More than the plants need is their plan.

So switching from day de hps 1000’s to 680 watt boards would only change the amount of power and heat produced. Not the amount of light. Again. The space is fully max lit regardless of tech.

You are thinking like a hobby grower. (Overthinking lol) one lamp thinking.

Plants outside in high light areas get more light than we can reproduce.
 
Aqua Man

Aqua Man

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I did not see the negatives you keep bringing up. When the plants get “tired” they simply lower their leaves to reduce their footprint for a while then perk up and go again.

And Bruce said they don’t need a dark period I that video I am sure.
I'm not saying they need it... just that under certain lighting they may and I feel its beneficial for more reasons... again not saying anything is needed.
 
Aqua Man

Aqua Man

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when you cover the room in light with a par meter to achieve consistency and no low spots it doesn’t matter what type of light you use. The par is maxed out for growing purposes. More than the plants need is their plan.

So switching from day de hps 1000’s to 680 watt boards would only change the amount of power and heat produced. Not the amount of light. Again. The space is fully max lit regardless of tech.

You are thinking like a hobby grower. (Overthinking lol) one lamp thinking.

Plants outside in high light areas get more light than we can reproduce.
Ok so what is par maxed out? I mean 2000ffd? 24 hrs straight.... absolutely not.
 
Aqua Man

Aqua Man

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when you cover the room in light with a par meter to achieve consistency and no low spots it doesn’t matter what type of light you use. The par is maxed out for growing purposes. More than the plants need is their plan.

So switching from day de hps 1000’s to 680 watt boards would only change the amount of power and heat produced. Not the amount of light. Again. The space is fully max lit regardless of tech.

You are thinking like a hobby grower. (Overthinking lol) one lamp thinking.

Plants outside in high light areas get more light than we can reproduce.
Wrong that 680w may produce more photons... than 1000w HID. It all depends on efficiency. Umol/watt directly correlates to the heat produced. Heat is a byproduct of efficacy.. its not a desired effect. Say you produce 3umol per watt the rest of the watt will be turned into heat.

So an LED at 3umol per watt vs a HPS at say 1.2umol per watt means the HID will produce a lot more heat and a lot less light (photons) at the same wattage
 
MIMedGrower

MIMedGrower

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Wrong that 680w may produce more photons... than 1000w HID. It all depends on efficiency. Umol/watt directly correlates to the heat produced. Heat is a byproduct of efficacy.. its not a desired effect. Say you produce 3umol per watt the rest of the watt will be turned into heat.

So an LED at 3umol per watt vs a HPS at say 1.2umol per watt means the HID will produce a lot more heat and a lot less light (photons) at the same wattage


a 680 hlg r spec and a de 1000 hps are about equal in usable light but the hps has more ir and far red light and tends to yield higher.

You are way overthinking this. They engineer the space for max light. They would do it for whatever lamps they use. Commercial growers never talk about higher yield with led. Just hvac and power savings.
 
Aqua Man

Aqua Man

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Let me try to explain another way. You agree adding co2 means the plants can handle more light right?

Why is that?

Because it improves the plants efficiency of photosynthesis (photosynthetic rate)

Now you may see that it improves very minimally in lower light... this is because even mid level lighting is not as efficient as it can be.

Under high light it makes a huge impact on growth... why because the plant is not able to process all of that light and the efficiency of photosynthesis was lower under high light than med light. We are talking efficiency here not growth or energy produced.

Now that's not to say there isn't a net gain there as there is but you are not getting as efficient photosynthetic rates as you do under lower lighting.... this happens up to a point where net photosynthesis will actually go down and the plant needs to slow photosynthetic rates to keep up. So it tacos and other things to reduce light capture. A simple dark period allows this to happen quickly. Under 24 hr light at high intensity it cannot catch up.

So what I'm saying is for those running 24/0 you absolutely cannot run as high of intensity as you can for 16/8 or 18/6.

 
Aqua Man

Aqua Man

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Notice the reference to the Calvin cycle... a short break helps them recover and thus increase in photosynthesis once back under light.

Basically you get more out of the light you give of your intensity is high with a short dark period.
 
Kanzeon

Kanzeon

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Ok so what is par maxed out? I mean 2000ffd? 24 hrs straight.... absolutely not.
This is an important distinction. I use much weaker lights for the 24 hour ladies than I do for the vegging or flowering ones. They can get fried from constant intense light.
 
Aqua Man

Aqua Man

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You can absolutely do 24/0 just would use less intensity.... and maybe a bit more power for a similar result but also lose out on some of the other benefits.

I mean the plants always performing processes to a certain point no matter the light cycle just to varying degrees.

I always say if ppl are growing autos they don't need as powerful of a light because they can give it 16-24hrs of light. So if 24 hrs they can literally use a light from 1/3-1/2 required by photoperiods.

It's all about the DLI. I wouldn't say one way is right or wrong... there are many variations inbetween that work well also.

There is always a reason we see different results. I'm just trying to explain why and why imo a dark period is a benefit in most cases but definitely not saying it's required. As with all things cannabis there are many right ways some maybe more beneficial... but the important part is just that we use what works for us.

I can definitely see your point about the microbes in hydro especially if sterile... if we manage the light intensity and co2 how much benefit is there to a dark period? Definitely less than other medias
 
Smithers

Smithers

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What about a polyphasic dark schedule, like Da Vinci... 20 mins every 4 hours or so it’s said.

I’m sure it’s been tested but I haven’t read much about it. Just jumping in, if the plant rests when overloaded does it respond to a few short spaced out dark periods rather than only one long one? Or does that scramble the plant with too much jet-lag?
 
TSD

TSD

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I think I'll believe the lady with a doctorate that just said the plants need a dark period for the microbiome to function properly and for the soil (assuming you're in soil) to be healthy. All living things need to rest to regenerate, that's just fact. She just said it will make the plant stressed and more susceptible to pests and disease, and that it could possibly lower the quality of the weed... so unless you're a commercial grow that only cares for rate of output... even then it makes no sense to me to do the 24 cycle.
 
TSD

TSD

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What about a polyphasic dark schedule, like Da Vinci... 20 mins every 4 hours or so it’s said.

I’m sure it’s been tested but I haven’t read much about it. Just jumping in, if the plant rests when overloaded does it respond to a few short spaced out dark periods rather than only one long one? Or does that scramble the plant with too much jet-lag?
I would assume that would just confuse and stress it out and possibly cause it to go hermie? 🤷‍♀️
 
Aqua Man

Aqua Man

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638
What about a polyphasic dark schedule, like Da Vinci... 20 mins every 4 hours or so it’s said.

I’m sure it’s been tested but I haven’t read much about it. Just jumping in, if the plant rests when overloaded does it respond to a few short spaced out dark periods rather than only one long one? Or does that scramble the plant with too much jet-lag?
All sorts of that has been tried out... there is soooo much more to this discussion like the time it takes a plant to change processes... hell light spectrum has a large impact and evidence to show a shift in red to far red can help speed that up... possibly making it viable... to my knowledge it's not as beneficial but I could be wrong and that's simply due to the time it takes to get the plant switched processes. So many factors that affect this it makes my head spin
 
Aqua Man

Aqua Man

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I think I'll believe the lady with a doctorate that just said the plants need a dark period for the microbiome to function properly and for the soil (assuming you're in soil) to be healthy. All living things need to rest to regenerate, that's just fact. She just said it will make the plant stressed and more susceptible to pests and disease, and that it could possibly lower the quality of the weed... so unless you're a commercial grow that only cares for rate of output... even then it makes no sense to me to do the 24 cycle.
But it does if you are lacking intensity... like I said there is a net gain to a point and all processesare haplening.... even if photosynthesis is reduced by 25% at high light its still net photosynthesis.. but photosaturation is a whole nother ball game.

Under low light the plants can easily keep up to 24/0
 
Aqua Man

Aqua Man

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Now if high light and no break at some point that 25% is going to actually reduce yield if compared to say 18/6 at 90+% efficacy for 18 hrs and 0 for 6
 
TSD

TSD

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But it does if you are lacking intensity... like I said there is a net gain to a point and all processesare haplening.... even if photosynthesis is reduced by 25% at high light its still net photosynthesis.. but photosaturation is a whole nother ball game.

Under low light the plants can easily keep up to 24/0
I'm sure they can, but not so sure they should... I just feel every living thingneeds rest🤷‍♀️
 

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