24 hour light vs. 18/6.

BobCajun

Well-Known Member
I've switched to continuous light now for clones and veg. No point even messing around with various photoperiods. Continuous means more growth and less temperature and humidity variation. I read that 24 hour is good for cuttings so might as well just use it for both. However, when I switch to flower I'll use 24 hours of dark on the first cycle to compensate. Whether or not that will make a difference I don't know, but it's easy to do so why not?

BTW, I read one article that said that a certain amount of light energy supplied over 24 hours produces more growth than the same amount supplied over a shorter photoperiod. Meaning dim light continuously beats bright light periodically, adding up to the same DLI. I'll see if I can find the article. At least it works that way with some plants, can't say how weed would react.
 
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rkymtnman

Well-Known Member
Since you get more veg growth in the same amount of time, as attested by many growers, why not use 24 hour, unless it's a warehouse and power rates are a big concern?
a wise older grower turned me on to 24/0. been using it since day 1.

i did try gas lantern once: had to run a heater during the dark times. didn't make sense: why run heat when i could just keep the lights on? went back to 24/0 after 2 days.
 

since1991

Well-Known Member
Its a hoot reading on the forums...threads that are temperature related (light = heat for instance) change with the seasons. Ive read several on the popular forums that are directly (but maybe even the posters dont even realize it) related to the winter and summer months.
 

TheHero

Member
I heard some guy say that in the flower cycle he leaves lights on for 36 hours and then 12 hour dark
My teacher of physics told me that human body is made to work within 36 hour day. He said that we are sent here, on this planet, as workers/employees to discover new world and our memories are deleted to make us not to suffer from wanting to get to real home.

Is there any experiment done that wasnt done within 24 hour cycle 20/4 18/6 24/0?..etc
 

since1991

Well-Known Member
My teacher of physics told me that human body is made to work within 36 hour day. He said that we are sent here, on this planet, as workers/employees to discover new world and our memories are deleted to make us not to suffer from wanting to get to real home.

Is there any experiment done that wasnt done within 24 hour cycle 20/4 18/6 24/0?..etc
I'd like to sit down and smoke a doob with yer physics teacher. Talk some heavy Stargate stuff !!!
 

Lite

Well-Known Member
My teacher of physics told me that human body is made to work within 36 hour day. He said that we are sent here, on this planet, as workers/employees to discover new world and our memories are deleted to make us not to suffer from wanting to get to real home.

Is there any experiment done that wasnt done within 24 hour cycle 20/4 18/6 24/0?..etc
Im gonna set my timers on my next veg for that schedule just for giggles... sounds interesting.
 

since1991

Well-Known Member
Ive tried and played around with all kinds of different lighting photoperiods...in veg and in flower. In veg my plants get 18 - 6. Ive found that this is the best compromise for seedlings/cutiings...preflowering vegetative plants and stock mother plants. And saves a little extra coin on the electric bill. That being said...cuttings that are rooting and preflowering almost ready for the flower rooms love them some 20 hour or constant 24 hour light. They both root and veg to size faster. Its not a deal breaker. But it is noticeable. Not for seedlings and mothers though. They like a nice 6 hours off dark period to rest up amd transpire from that full long day of photosynthesis production. So 18 - 6 it is. Also..if you have a dark period veg room..its not so critical compared to a 12-12 flower room to have it completely dark. When my veg lights shut off for 6 hours..I pop in there all the time for maintenance and what not. I sometimes even leave veg room doors open. Light leaks arent a factor in my veg room..which is actually a big 7x7x7 tent packed with t5's. Ive even left cloning rack t5's on 24 hours while the mothers t5's shut off for 6. But in the past ive had wierd clones/genetics start showing major pistil preflowers from going from 24 hrs light under the clone rack to 18-6 under the bigger t5's they share with mothet plants. I almost always chuck these strange genetics as Iam not taking any chances. I will just about try anything...once. Gifted/traded cuts..seed plants...anything. But at the slightest hint of acting funny and it seems they dont wanna fit the program...they get culled. Back in the day the strains I ran from Cali Connection come to mind. Some of those strains just like autoflowered or wanted to with the slightest hint of a dark period. One of the reasons i dont run CC gear anymore. Ive built up quite a stable of keepers and I run a perpetual rotation system with a test tent..a big veg tent..and 2 big flower rooms. Ive had untested hermie gear in the past blow out my strains and fuk them all up. Lost patients because I didnt have the usual meds they expected. Long ago. So I cant afford to take chances anymore. Everything new gets ran in the test tent at least once then if it makes the cut..goes to the veg tent for more observation. Alot of gear i get off the streets doesnt make it. Mainly spider mites/pests or wierd diseases.
 
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Odin*

Well-Known Member
Is there any experiment done that wasnt done within 24 hour cycle 20/4 18/6 24/0?..etc
Yes. 16-32hr day/night cycles. Relative and constant “Day”. Relative was 1:2 day/night (eg; 10.66 day/21.33 night for 32hr cycle), constant was 8 hour days (eg; 8 day/24 night for 32hr cycle). Cycles less than 24hrs delayed flowering (compared to 24hr cycles), cycles greater than 24hrs accelerated flowering, with “relative” having the advantage over “constant”.
 

since1991

Well-Known Member
What is the best light cycle for getting a plant to reveg?
I always tried 24 hours for a reveg but down to 18 works as well. Its the phytochrome in the plants that they built up and you want to regulate back into a more veg period. They grow (for me) very funky for awhile. I took some Dream cuts from my outdoor when the branches were well underway in flower and these cuts are taking forever to resume natural looking growth and phylotaxy. Curly single bladed leaves. Still popping trichomes. It takes time but keep them on a minimum 18 hours vegetative light period and a veg nute regimen and they will slowly snap back into a veg plant. Lay off all the kelps and seaweeds/additives and whatnot as well. Just regular veg fertilizer. Transplant into a pot up you can as well. And be prepared to wait. Takes awhile. If you transplant to a bigger pot you can even hack off about a quarter to a third of the vwry bottom of the root ball if they are root bound. This makes roots re grow very fast and slaps them gals back into veg even quicker.
 

Chunky Stool

Well-Known Member
I always tried 24 hours for a reveg but down to 18 works as well. Its the phytochrome in the plants that they built up and you want to regulate back into a more veg period. They grow (for me) very funky for awhile. I took some Dream cuts from my outdoor when the branches were well underway in flower and these cuts are taking forever to resume natural looking growth and phylotaxy. Curly single bladed leaves. Still popping trichomes. It takes time but keep them on a minimum 18 hours vegetative light period and a veg nute regimen and they will slowly snap back into a veg plant. Lay off all the kelps and seaweeds/additives and whatnot as well. Just regular veg fertilizer. Transplant into a pot up you can as well. And be prepared to wait. Takes awhile. If you transplant to a bigger pot you can even hack off about a quarter to a third of the vwry bottom of the root ball if they are root bound. This makes roots re grow very fast and slaps them gals back into veg even quicker.
I've got a cindy99 under 18/6 and I'm not sure if it's going to do squat. I left quite a few buds but several fell off.
It had a rough life anyway & might not be up to the challenge. Root rot almost killed her early in flower. All of the fan leaves dropped & she was stunted, big-time.
Poor plant.
I feel bad for her. :-(
 

ANC

Well-Known Member
Yeah, I like me some 20/4 vegging. By day 20 it received 40 hours (or almost two days) of light more than 18/4. I do believe they need a rest period.

My best luck with reveging was outdoors, just leave the plant with no trimming or stealing buds (had some weird insects nest in the plants) We are in a winter rain area so they never dried out even though I left them to do what they wanted. The plants lived for 11 months.
 

since1991

Well-Known Member
I've got a cindy99 under 18/6 and I'm not sure if it's going to do squat. I left quite a few buds but several fell off.
It had a rough life anyway & might not be up to the challenge. Root rot almost killed her early in flower. All of the fan leaves dropped & she was stunted, big-time.
Poor plant.
I feel bad for her. :-(
Do you have backup copies of her? Rooted cuts? If you do..I wouldnt bother with an attempt at reveg. Especailly if youve had a pythium problem or if she just had a rough life. You can do it for an experiment or if youve never did a reveg before. But honestly...unless its a variety I just cant do without and I have no copies of her...they just take forever amd valuable space/electric bill to be really worth the effort.
 

since1991

Well-Known Member
I know its hard but a good grower knows when to hold em amd knows when to fold em. Its tough for me even after all these years to cull plants.
 

Chunky Stool

Well-Known Member
Do you have backup copies of her? Rooted cuts? If you do..I wouldnt bother with an attempt at reveg. Especailly if youve had a pythium problem or if she just had a rough life. You can do it for an experiment or if youve never did a reveg before. But honestly...unless its a variety I just cant do without and I have no copies of her...they just take forever amd valuable space/electric bill to be really worth the effort.
Nope, no clones. It was a seed I got from a buddy and it started flowering while still in a solo.
Then I used too much calcined clay in my soil mix, which caused it to retain more water. Tried to put her on the same schedule as my other outdoor plants, which was a huge mistake.
It's a nice pheno. Very frosty & fruity.
Maybe I'll use more light. Got three small lights on her right now. 75w total, two are blurple LED lamps.
I could just break out a real hood and run a 400w MH.
It would either perk her up or finish her off.

Forgot to mention that she had a variety of bugs from being outdoors. It took a couple of weeks to kill them all for good. (spinosad + insecticidal soap)

I'm also popping some beans as plan B. 8)
 

Odin*

Well-Known Member
Not going to argue the 24/0 guys, just want to point out a few facts.

24/0 alters the plant’s metabolic processes. They will acclimate to the constant light, but detrimental to overall development. After 8 day’s of 24/0, starch buildup VS chlorophyll degradation begins. Offsetting this via temp variance does not negate the time needed to “reaclimate” to dark periods, which means delayed flowering due to chlorosis/slowed ratemof photosynthesis.

Are we trying to increase vegetation weight via starch/sugar buildup, or are we preparing for bloom? This depends on the grower, their regimen, knowledge, and goals.
 

since1991

Well-Known Member
Not going to argue the 24/0 guys, just want to point out a few facts.

24/0 alters the plant’s metabolic processes. They will acclimate to the constant light, but detrimental to overall development. After 8 day’s of 24/0, starch buildup VS chlorophyll degradation begins. Offsetting this via temp variance does not negate the time needed to “reaclimate” to dark periods, which means delayed flowering due to chlorosis/slowed ratemof photosynthesis.

Are we trying to increase vegetation weight via starch/sugar buildup, or are we preparing for bloom? This depends on the grower, their regimen, knowledge, and goals.
YES!!! I can dig this. Keep it coming growers. The Truth shall set us free.
 
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