"Plants Need Sleep"

TheYokel

Well-Known Member
The only reason to use 20-4 over 24-0 is saving electricity.
I could think of a few reasons...

Promoting longer node stretching for one. Some people have screens to fill and don't want to start with a 3" plant.

Don't be so general. For every reason you have for loving 24/0... someone else has a reason they love 20/4 or 18/6 just as much.
 

churchhaze

Well-Known Member
Don't get me wrong. While I do use 24-0, I don't see it as the only way to go. Saving electricity is a perfectly good reason. if you really want stretch, I guess that could be a good reason too... if you really want stretch.

It's just that I see a lot of people, even very experienced, making general claims like "weed doesn't grow roots at night". Well obviously since I grow with 24-0 (i don't wanna get another timer), I know that my plants do indeed have lots of roots, so the claims that they don't must be false.

I've heard people make claims that 20-4 will outright veg faster, but I've never actually seen proof of this.

Uncle Ben was asking whether we could believe it if his plants enjoyed a 4 hour nap. I don't see how you could determine a plants happiness other than its growth rate and overall health. I guess I lack plant empathy.

I could think of a few reasons...

Promoting longer node stretching for one. Some people have screens to fill and don't want to start with a 3" plant.

Don't be so general. For every reason you have for loving 24/0... someone else has a reason they love 20/4 or 18/6 just as much.
 
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TheYokel

Well-Known Member
Don't get me wrong. While I do use 24-0, I don't see it as the only way to go. Saving electricity is a perfectly good reason. if you really want stretch, I guess that could be a good reason too... if you really want stretch.

It's just that I see a lot of people, even very experienced, making general claims like "weed doesn't grow roots at night". Well obviously since I grow with 24-0 (i don't wanna get another timer), I know that my plants do indeed have lots of roots, so the claims that they don't must be false.

I've heard people make claims that 20-4 will outright veg faster, but I've never actually seen proof of this.
20/4 seems to grow thicker stems, I do believe that from my limited indoor experience. I've tried quite a few light periods for my clones and my mama bushes, and 20/4 with the clones and seedlings seems to give the thickest stem. They stretch more than a 24/0 plant, though...
 

az2000

Well-Known Member
A pulse of 730nm at lights out will make it even more likely to leave veg, not less likely.
I probably overlooked that the topic was solely veg. I brought up the 730nm (5-10 minutes at lights out) to illustrate how the "state" can be achieved faster, allowing lights to remain on longer in flower. Instead of running 12/12, a person can run 14/10, get 2 hours more flowering production because they didn't have to give the plant 2 hours of darkness just to get into that "state."

If you're talking about veg, I agree the 730nm thing doesn't make sense. The plant doesn't need to enter the "state" to maintain veg. It only needs to enter the "state" in flower to maintain flower. (I know you know this. I'm just being thorough for others who may find this thread.).
 

GrowerGoneWild

Well-Known Member
but it's not true that 20/4 will produce better than 24-0.
Whether you use 18/6, 20/4, 24/0 is up to the grower, but in my experience, it doesn't matter.
What does matter is that you keep night lengths short enough so the plant does not flower.

The only reason to use 20-4 over 24-0 is saving electricity.
Whew!.. Ya saved me some typing.

So with little to no difference, and 24/0 the least likely to cause flower just keep the lights on. 24/0 isn't a perfect solution either.. It will not flip every cutting from bloom back to veg, its more likely to go back to veg in 24/0.

I still dont understand how people came up with the 20/4 timing. What about 22/2?.. 23/1.. etc.

I think my ladies need a nap because they look stressed.. after they dream about sex they look so much better.
 

Uncle Ben

Well-Known Member
This would be counter-intuitive. The only reason 20-4 works as well as 24-0 is because the night length isn't long enough for %Pfr to reach the threshold. It would make more sense to interrupt the night with any other color than 730nm to keep the phytochrome state in Pfr.

A pulse of 730nm at lights out will make it even more likely to leave veg, not less likely.
Could care less cause in the real world accumulation of phytochrome is such that when I go with 12/12 I get a flowering response in days.

I can and do, all the time, bring a germinated seed to an adult flowering stage within 4 weeks, producing a nice yielding plant that finishes out around 42" H.
 

Uncle Ben

Well-Known Member
I still dont understand how people came up with the 20/4 timing.
I tried 20/4 lighting as a compromise between 24/0 and 18/6 15 years ago.

Works for me.....

Finding a plant's light saturation point is what really matters. IOW, how many total photons received during a day produces the most carbos.

UB
 
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Uncle Ben

Well-Known Member
Uncle Ben was asking whether we could believe it if his plants enjoyed a 4 hour nap. I don't see how you could determine a plants happiness other than its growth rate and overall health. I guess I lack plant empathy.
I was being facecious. :mrgreen:

I do know that I will never go against the grain or laws of mother nature. Plants, animals, fish..... need a rest.
 

GrowerGoneWild

Well-Known Member
I tried 20/4 lighting as a compromise between 24/0 and 18/6 15 years ago.
Works for me.....
Finding a plant's light saturation point is what really matters. IOW, how many total photons received during a day produces the most carbos.
Meh.., I started using 24/0 out of need, I had a mom flower out on me, and I was messing with cuts that had already flowered. 24/0 worked for me. I was running 18/6. That was at least 10 years ago.. The only time I will relax my veg time cycle is if i'm veging with HID lights.

If light saturation is the point, then I would rather err to having a longer on time. Casual observations have not proven 24/0 to be much better or any worse than with 18/6 from a growth stand point.

If it works for you.. then keep doing it...
 
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GrowerGoneWild

Well-Known Member
I was being facecious. :mrgreen:

I do know that I will never go against the grain or laws of mother nature. Plants, animals, fish..... need a rest.
Debatable.. There are many forms of life that literally do not stop. Fungi, bacteria, yeasts. Its my opinion that fungi are more similar to plants than animals or fish.. Like my little buddies cubenis.
 

churchhaze

Well-Known Member
One of the more controversial tricks people have been using recently is using 730nm leds for 5 minutes after lights out to convert %Pfr to 0 quicker. (all active form into inactive form) The people who have been using it claim to be able to take a week off flowering by speeding up the flowering response.

Like with a lot of things, I needed to try it. I built a 730nm array a few months ago, and used it for one grow so far. From my own experience, what I can tell you is that 730nm really is the "low quality" color that causes stretching and sleeping. No doubt in my head now. Holy stretch... batman.... It makes branches think they're shaded. I think it made my plant think it was getting 14 hours of night instead of 12, but in practice I'm not sure the best way to use these things.

Like you're saying though, most people probably don't need them, but haven't you always wanted a sleep ray? It's probably more of a toy for HPS growers. Many suspect that the dim reddish glow of the HPS lamp turning off acts similar to the 730nm, but i don't think anyone's actually measured the spectrum from the glow.


Could care less cause in the real world accumulation of phytochrome is such that when I go with 12/12 I get a flowering response in days.

I can and do, all the time, bring a germinated seed to an adult flowering stage within 4 weeks, producing a nice yielding plant that finishes out around 42" H.
 

churchhaze

Well-Known Member
Another interesting thing about 730nm far-red is how well it penetrates foliage. It's a bit surreal because of how poorly 660nm red penetrates, yet looks exactly the same to the human brain.

If you turn all the other lights out and view your plants in only the 730nm, it looks almost as if all the leaves are white paper.
 

TheYokel

Well-Known Member
Another interesting thing about 730nm far-red is how well it penetrates foliage. It's a bit surreal because of how poorly 660nm red penetrates, yet looks exactly the same to the human brain.

If you turn all the other lights out and view your plants in only the 730nm, it looks almost as if all the leaves are white paper.
Anyone else get a science chubby and feel the need to try this?
 

bryleetch

Well-Known Member
One of the more controversial tricks people have been using recently is using 730nm leds for 5 minutes after lights out to convert %Pfr to 0 quicker. (all active form into inactive form) The people who have been using it claim to be able to take a week off flowering by speeding up the flowering response.

Like with a lot of things, I needed to try it. I built a 730nm array a few months ago, and used it for one grow so far. From my own experience, what I can tell you is that 730nm really is the "low quality" color that causes stretching and sleeping. No doubt in my head now. Holy stretch... batman.... It makes branches think they're shaded. I think it made my plant think it was getting 14 hours of night instead of 12, but in practice I'm not sure the best way to use these things.

Like you're saying though, most people probably don't need them, but haven't you always wanted a sleep ray? It's probably more of a toy for HPS growers. Many suspect that the dim reddish glow of the HPS lamp turning off acts similar to the 730nm, but i don't think anyone's actually measured the spectrum from the glow.
I believe you can shorten the darkness using the far red light before lights out, that may have prevented some stretch. If it truly does speed up a 2 hour conversion process into 5-10 minutes then why not cut down the dark to 10 hours to avoid it sensing it's getting 14 hours of dark. I thought that was the whole point of it, to have a shorter dark period than 12 hours in order to reach the threshold every morning that keeps flowering going.

Also here's another good link for anyone, it ties circadian rhythms into the discussion about phytochromes but note the part about circadian rhythms is referring to long day plants and it goes on to say that little is understood in terms of short day plants(another misnomer), or long night plants, example: cannabis. It also backs up the claim that far red light speeds up Pfr conversion by two hours http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/P/Photoperiodism.html
Found it interesting too that it points out if a plant is expose to red light during the dark it completely undoes the conversion process but if it is then exposed to far red it can be redone, crisis averted.
 

churchhaze

Well-Known Member
It's because I wasn't 100% sure what was theory and what was reality. It was my first attempt at using a 730nm array. I'm thinking of doing 14 hours light with the 730nm pulse next time, but I'm still not entirely sure what the difference will be. I can only make educated guesses.

If it truly does speed up a 2 hour conversion process into 5-10 minutes then why not cut down the dark to 10 hours to avoid it sensing it's getting 14 hours of dark. I thought that was the whole point of it, to have a shorter dark period than 12 hours in order to reach the threshold every morning that keeps flowering going.
 

bryleetch

Well-Known Member
It's because I wasn't 100% sure what was theory and what was reality. It was my first attempt at using a 730nm array. I'm thinking of doing 14 hours light with the 730nm pulse next time, but I'm still not entirely sure what the difference will be. I can only make educated guesses.
I completely understand, at least you have the tool now to play around with and see if anything works. That's really the only way to know for sure with just about everything nowadays
 

az2000

Well-Known Member
Found it interesting too that it points out if a plant is expose to red light during the dark it completely undoes the conversion process but if it is then exposed to far red it can be redone, crisis averted.
In medicine they have "rescue drugs" to counteract an overdose to another medication. This could be called a "rescue light." Everyone should keep one on hand for those emergencies when we have to expose plants to light. Just hit them with the rescue light and it's like it never happened.

That's cool to know.
 

TheChemist77

Well-Known Member
could someone answer my question?? do clones really root faster under 18/6?? ive always rooted under 24 hrs of light and after rooted put them undr 18/6...if they truly root faster under 18/6 i can do away with my clone room, and just put them in the 18/6 veg room..
 

TheYokel

Well-Known Member
could someone answer my question?? do clones really root faster under 18/6?? ive always rooted under 24 hrs of light and after rooted put them undr 18/6...if they truly root faster under 18/6 i can do away with my clone room, and just put them in the 18/6 veg room..
I have my clone dome in my room with my mama bush, and they root under 20/4. I'm not sure anything about lighting periods and times for clones to root. Just have anecdotal evidence.

Would be great info though.
 
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