18 hours too much light for my plants?

[detroitjoe]

Ok plants don't rest I agree. They change processes during lights on and off. Both are crucial imo.

i agree. With lights on, certain systems run and when the lights are off, certain systems run.

They absolutely do get used to a light cycle and will start to droop a bit as they slow transpiration rates in anticipation of a dark cycle.

The plant is pre-programmed. It will act accordingly to the input of the environment.
The plants programmed (amongst other things) to measure the duration of daylight /darkness IE: being able to take it from veg stage to flower stage by reducing/increasing amount of light
Less light, winter is coming - time to reproduce ( flower mode )
Longer light, its still summer - keep vegging.


IN A HEALTHY PLANT:
In darkness, the leaves "droop" because their is no need for them to stay up. Its dark.. no sun...no need to use that system.
If they droop and flop around, you have an unhealthy plant.
If they droop and still have strength ..its healthy.

If it droops and the light is on, again you have a problem.

They will also do then when they can no longer keep up the rates of photosynthesis and transition more towards photorespiration if under very high light.

What do you mean by high light. INTENSITY?
If so, yes and no.


The argument here is CAN YOU VEG PLANTS UNDER 24 HOURS OF LIGHT .


I say you can and the O.P says you cant.
what do you say?

 

[detroitjoe]

Like they don’t need more light. It’s why they droop prior to sunset or just before lights off. I was being very simplistic to the OP.

false and thanks for the reply.
look at it this way:
the suns out, the plant is enjoying a full day of sun. leaves are up in V formation and all systems are a go.

It senses the light and water/nute & mineral uptake resumes.

If my leaves shut down while in daylight...there is a problem. either its dry...maybe hungry..maybe the roots locked up...maybe im short in minerals /food.
It shuts down because its lacking in something and it isnt sleep.

 

[freezeland2]

false and thanks for the reply.
look at it this way:
the suns out, the plant is enjoying a full day of sun. leaves are up in V formation and all systems are a go.

It senses the light and water/nute & mineral uptake resumes.

If my leaves shut down while in daylight...there is a problem. either its dry...maybe hungry..maybe the roots locked up...maybe im short in minerals /food.
It shuts down because its lacking in something and it isnt sleep.

I’m not saying it’s going to go to sleep. It’s had enough useful light and it knows to transition to its dark phase.

 

[Aqua Man]

The plant is pre-programmed. It will act accordingly to the input of the environment.
The plants programmed (amongst other things) to measure the duration of daylight /darkness IE: being able to take it from veg stage to flower stage by reducing/increasing amount of light
Less light, winter is coming - time to reproduce ( flower mode )
Longer light, its still summer - keep vegging.

No it has nothing to do with summer or winter. It's the hormones produced under daylight conditions that prevent it from flowering. As the light shifts so does the balance.

IN A HEALTHY PLANT:
In darkness, the leaves "droop" because their is no need for them to stay up. Its dark.. no sun...no need to use that system.
If they droop and flop around, you have an unhealthy plant.
If they droop and still have strength ..its healthy.

If it droops and the light is on, again you have a problem.

Lol no... they droop because transpiration all but stops since it's driven by photosynthesis. It's absolutely normal for them to droop just before and during lights out. Feel free to go watch any time-lapse ever made.

What do you mean by high light. INTENSITY?
If so, yes and no.

Yes intensity and absolutely yes there isn't a no in this.

The argument here is CAN YOU VEG PLANTS UNDER 24 HOURS OF LIGHT .


I say you can and the O.P says you cant.
what do you say?

Yes you can but you are limited on intensity and the plant is missing some in my opinion important processes by doing so.

 

[Aqua Man]

false and thanks for the reply.
look at it this way:
the suns out, the plant is enjoying a full day of sun. leaves are up in V formation and all systems are a go.

It senses the light and water/nute & mineral uptake resumes.

If my leaves shut down while in daylight...there is a problem. either its dry...maybe hungry..maybe the roots locked up...maybe im short in minerals /food.
It shuts down because its lacking in something and it isnt sleep.

Or to much light.... and it needs a dark period to process the sugars it has produced because it's producing them faster than it can use them.... have Google date with photorespiration and photosaturation.

 

[growsince79]

i agree. With lights on, certain systems run and when the lights are off, certain systems run.

The plant is pre-programmed. It will act accordingly to the input of the environment.
The plants programmed (amongst other things) to measure the duration of daylight /darkness IE: being able to take it from veg stage to flower stage by reducing/increasing amount of light
Less light, winter is coming - time to reproduce ( flower mode )
Longer light, its still summer - keep vegging.


IN A HEALTHY PLANT:
In darkness, the leaves "droop" because their is no need for them to stay up. Its dark.. no sun...no need to use that system.
If they droop and flop around, you have an unhealthy plant.
If they droop and still have strength ..its healthy.

If it droops and the light is on, again you have a problem.



What do you mean by high light. INTENSITY?
If so, yes and no.


The argument here is CAN YOU VEG PLANTS UNDER 24 HOURS OF LIGHT .


I say you can and the O.P says you cant.
what do you say?

You absolutely can veg at 24hrs. Nobody is saying you can't. But beyond a certain intensity, higher intensity will harm the plant. That's an unquestionable fact. The same plant grown under 16 hours can handle a higher intensity. That's proven in university studies and my own eyes.

 

[Aqua Man]

false and thanks for the reply.
look at it this way:
the suns out, the plant is enjoying a full day of sun. leaves are up in V formation and all systems are a go

I will add that the sun's intensity changes throughout the day and its not subjected ro peak light for 18 hrs but rather only about 3-4 tops if uts a clear day and no clouds... you cannot compare sunlight to a high intensity light for 18hrs. It just doesn't work that way

 

[Aqua Man]

You absolutely can veg at 24hrs. Nobody is saying you can't. But beyond a certain intensity, higher intensity will harm the plant. That's an unquestionable fact. The same plant grown under 16 hours can handle a higher intensity. That's proven in university studies and my own eyes.

Shouldn't even be a question. Absolutely proven. This is why co2 elevation helps. Increased photosynthetic rates allow for a higher intensity.

Dark cycles help the plant use up the stored nutrients without adding more. It's no coincidence that the most efficient photosynthesis happens early in lights on. This is where the whole 6 on 6noff came from and all these altered light schedules. But the issue was the plant takes time to change processes. With the new info on far red and info red speeding these processes up you may see them become a thing again... only possibly viable this time.

 

[Cashmeh]

So do the studies suggest 18/6, 16/8, 20/4, or what about 17/7. I only ask because I know people have always talked about saving money on light bills and in my thought process spending extra money to produce fast quality is worth it.

So i dont know how the sugars are created, or what their purpose is, or how or why they are broken down. Off to some NPK youtube videos I guess. Yet I am learning far more here.

Would the system its in determine how fast the sugars break down, say soil vs aero?

Also I run my lights on stupid high now, and I dont run Co2, I have too much CFM through the tents for cooling to make it even work. That said, since im 18/6, and a really good hydro system, am I doing more harm than good? Will I gain more growth if I had C02? Yet without and high light intensity, like im doing now, what is the issue again? Im trying to keep up

Im not saying anyones wrong either lol, i have no idea what yall are even talking about, but I might soon

 

[Nectarivorous]

It's all about limiting factors. While there is a lot more to environment, your Trinity are nutes, light, CO2. Drive the lights too hard and you will push plants to a point that they cannot process enough nutrients to keep up without CO2 being added to help process that amount of nutes.

My understanding of the question about correct number of hours is that this is why real grow scientists, as in ones with degrees in chemistry and biology who run university grow programs and the like, talk in terms of DLI. Daily light integral gives you a hard number of how many photons a plant can actually do anything with, based of course on CO2 levels. Then it's not about the hours, just the number of photons, whether they are delivered over 18, or at slightly higher intensity for 16. I haven't read any studies as to whether one or the other is preferable, and I imagine it would be different for sativa and indica.

 

[Aqua Man]

So do the studies suggest 18/6, 16/8, 20/4, or what about 17/7. I only ask because I know people have always talked about saving money on light bills and in my thought process spending extra money to produce fast quality is worth it.

So i dont know how the sugars are created, or what their purpose is, or how or why they are broken down. Off to some NPK youtube videos I guess. Yet I am learning far more here.

Would the system its in determine how fast the sugars break down, say soil vs aero?

Also I run my lights on stupid high now, and I dont run Co2, I have too much CFM through the tents for cooling to make it even work. That said, since im 18/6, and a really good hydro system, am I doing more harm than good? Will I gain more growth if I had C02? Yet without and high light intensity, like im doing now, what is the issue again? Im trying to keep up

Im not saying anyones wrong either lol, i have no idea what yall are even talking about, but I might soon

There is no absolute right and wrong you adjust the light intensity to what the plants can handle for a given photo period. This varies from strain to strain and pheno to pheno

 

[chemistry]

If plants don't need a period of darkness, then why over millions of years did they perfect the art of breathing in CO2 at night, and oxygen during the day? The reason they droop at night is because there's no light to photosynthesis.

 

[Nectarivorous]

If plants don't need a period of darkness, then why over millions of years did they perfect the art of breathing in CO2 at night, and oxygen during the day? The reason they droop at night is because there's no light to photosynthesis.

It's a good point but I think you got the gases backwards

 

[chemistry]

It's a good point but I think you got the gases backwards

Its meant to say breathing out oxygen in the day, and taking in CO2 at night.

 

[Madmax]

Its meant to say breathing out oxygen in the day, and taking in CO2 at night.

Nice save bro..i was coming for ya

 

[chemistry]

Nice save bro..i was coming for ya

Got a rare day off, so thought I'd have a sly toke, and now I'm battered, should have got on with my chores. lol Maybe still the wrong way round.

 

[Madmax]

Haha...just about to have a toke myself and wreck the day....what day is it .where am i ..was that the sofa girl toke

 

[chemistry]

Haha...just about to have a toke myself and wreck the day....what day is it .where am i ..was that the sofa girl toke

Your not going to believe it, but yes, the last two decent buds from the Sofa Surprise, still smells like cheap sweets. lol Was hoping to find a seed, but no. Better have another scramble down the back of the settee. lol

 

[dbrzz]

I strongly suspect this is not entirely true. If so we would just run lights 24/7 during veg.

The cost of electricity is the reason why people dont run 24/7!! The plants dont care, but the growth vs cost of energy ratio is the problem. The schedules of 16/8 or 18/6 is the most cost effective for growers as the extra growth value in bud weight gained by 24 hrs of light, is lost due to the cost of electricity….

To sum it up….. Cannabis auto flower plants do not need any darkness to grow healthy. The light schedules are used to maximize production of buds and reduce costs of electricity in production. Photo period cannabis, needs a dark period to initiate flowering, but running 24/7 in veg is perfectly fine , although a waste of electricity. I hope this helps. Read Ed Rosenthal, the grow Master!!

 

[dbrzz]

I strongly suspect this is not entirely true. If so we would just run lights 24/7 during veg.