9/12 light cycle

BobCajun

Well-Known Member
You may have heard of a 6/12 light cycle, supposedly yielding the same weight as 12/12 in less time. Another person reported success with a 7/12 cycle. The problem being that it's not easily possible to use such non-24 hour cycles with a regular weekly timer. Well, oddly enough nobody ever tried a 9/12 cycle, which can fit perfectly into a week and which provides 8 dark periods rather than 7. So in 7 weeks of that you would gain an extra week of ripening speed, 7 weeks equaling 8 12/12 weeks. I figure 9 weeks of that would give very ripe and well developed buds, equaling about 10 weeks and 2 days.

Here's the schedule I came up with. How did nobody try this before, right? A 9 hour day is pretty solid actually. I would be worried if I used 6 or 7 though and what's the point? I don't need it to be faster than 9 weeks, three convenient chambers spaced 3 weeks apart. Not as convenient dividing 10 weeks into 3, get stuck with an extra week. Also cuts back on power somewhat, I guess by 25%, didn't work it out exactly. That's not bad really. Just gotta check the schedule to see when you'll have to water next or whatever.

Actually I see there's 3 events on Sunday so I'll have to work on this some more. Might not work after all unless I just made a mistake typing that schedule up. Probably why nobody tried it before, it gets screwed up on one day. Maybe have to do it manually on Sundays. Have to manually turn it on at 10 pm Sunday, I guess would be most convenient. Of course the whole schedule could be reworked so that the on time is whenever you want on Sunday, or whatever day you choose the schedule to end on. Have to make sure it goes to "on auto" and not just "on" though. Gotta click it twice instead of just once.

on 7pm Mon
off 4am Tue

on 4pm Tue
off 1am Wed

on 1pm Wed
off 10pm Wed

on 10am Thur
off 7pm Thur

on 7am Fri
off 4pm Fri

on 4am Sat
off 1pm sat

on 1am Sun
off 10am Sun

on 10pm Sun
off 7am Mon
 
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BobCajun

Well-Known Member
Okay how about this one? I arranged it for easier programming by grouping the days together, just that the times may look backwards sometimes, pm before am. Let me know if there's any mistakes in it please.

Mon on 7pm
Mon off 7am

Tue on 4pm
Tue off 4am

Wed on 1pm
Wed off 10pm

Thur on 10am
Thur off 7pm

Fri on 7am
Fri off 4pm

Sat on 4am
Sat off 1pm

Sun on 1am
Sun off 10am

Sun manual on 10pm
 
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Cletus clem

Well-Known Member
Yes Sir and better. Look up WiFi plug with the App. Cycled, scheduled, and count down functions. Cheap as a regular timer.

Been considering one for myself.
I just so happen to have 2 tents for test run purposes that if i dont have new genetics to play with i plan on playing around with shit like this! Look into i will! ⏲
 

torontoke

Well-Known Member
Is there a cycle timer you could set easily to run like this?
It's not just the timer that makes this idea tricky but also most places have different prices on energy use. Day vs night and when u use a schedule that doesn't add up to 24 u will float in and out of peak rates and nullify a certain percentage of savings
 

BobCajun

Well-Known Member
I decided not to use the cycle after all, because I like to split the grow up so half is on for 12 or 13 hours and the other half is off, so that there's less heat buildup. As it is, I'm running 13 hours so there's two hours of overlap but it's not that bad. With 12/12 it works perfectly, I'm just trying to get more growth by using 13/11.

I read an article about hemp farming which said that with day lengths of 13 hours 40 minutes or less it matured at a similar rate, meaning shorter days didn't speed it up. But they said that days of 14 hours 40 minutes or longer resulted in later maturation and larger plants. Here's the page. I figure if hemp is like that then probably so is cultivated drug type Cannabis. Using shorter days than 13:40 may be pointless. I'm sticking with 13 for now though, can't take any chances. I've used 13 before so I know it works.
 

BobCajun

Well-Known Member
It's not just the timer that makes this idea tricky but also most places have different prices on energy use. Day vs night and when u use a schedule that doesn't add up to 24 u will float in and out of peak rates and nullify a certain percentage of savings
Yeah some places are like that. It's a cycle which would only be practical for some people. I just found it interesting that eight 21 hour days fit perfectly into a week and that 9/12 looks like a pretty solid photoperiod. Maybe someone will try it someday and report results. People have certainly tried weirder ones.
 

torontoke

Well-Known Member
I decided not to use the cycle after all, because I like to split the grow up so half is on for 12 or 13 hours and the other half is off, so that there's less heat buildup. As it is, I'm running 13 hours so there's two hours of overlap but it's not that bad. With 12/12 it works perfectly, I'm just trying to get more growth by using 13/11.

I read an article about hemp farming which said that with day lengths of 13 hours 40 minutes or less it matured at a similar rate, meaning shorter days didn't speed it up. But they said that days of 14 hours 40 minutes or longer resulted in later maturation and larger plants. Here's the page. I figure if hemp is like that then probably so is cultivated drug type Cannabis. Using shorter days than 13:40 may be pointless. I'm sticking with 13 for now though, can't take any chances. I've used 13 before so I know it works.
Well I can tell u first hand that shorter days do speed it up and in fact even 11.5 vs 12 can show a noticeable difference.
So if the article is full of that kind of info I'd read more into it.
 

BobCajun

Well-Known Member
Well I can tell u first hand that shorter days do speed it up and in fact even 11.5 vs 12 can show a noticeable difference.
So if the article is full of that kind of info I'd read more into it.
Maybe due to Indica genetics. Still, I have read posts about people growing normal drug weed in 14 hour days and getting great yields. Maybe about 14 hours is best, between 13:40 and 14:40, right in the sweet spot for monster yields.

Sample post.
So I know a guy that's been growing indoor and outdoor since about 97 and he was telling me that the past few grows he's been doing 24/0 veg and 14/10 flower. He says the buds are way bigger and much denser and the yield is almost doubled. He said when doing 18/6 and 12/12 he would get a little more than 1.5 lbs per 1000w. He says with this method he's pulling almost 3 lbs per 1000w. Anybody else every hear anything on this before?

page
Hmm, doubled yields eh? 3 lbs is what, about 1350 g? A yield of 1.35 g/w is unheard of with HPS normally. Actually reminds me of a thread on here, 3 lbs to a light. One guy said the strain Hash Plant would reveg under 14/10 though, so it doesn't work with all strains apparently, probably better with hybrids than full or close to full Indicas. Also it seems advisable to start with a week or two of 12/12 to get flowering underway.
 
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torontoke

Well-Known Member
1.35 g/w is unheard of?
Double the yield by increasing flower time.... sounds a tad easy imo but then again I've never tried it so only one way for you to find out.
Any mention of how many extra days it went?
 
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BobCajun

Well-Known Member
1.35 g/w is unheard of?
Double the yield by increasing flower time.... sounds a tad easy imo but then again I've never tried it so only one way for you to find out.
Any mention of how many extra days it went?
I don't know, I linked the page. Most HPS growers get about .5 g/w. Now about the 14 hour day, I guess the 13h 40m figure must be the magic number, because some strains do stay in veg mode with 14 hours but probably not many with 13:40.
 

BobCajun

Well-Known Member
Lol your plants are all like "wtf planet am I growing on?"
Now I have the flowering timers set to 13:40 on. I'll see how that works out. I want as long days as possible without causing any problems. Since the article said 13:40 I may as well give it a try. Articles about photoperiodism say short day plants flower with less than 14 hour days, so 13:40 sounds valid to me. 14 would be pushing it though.
 

BobCajun

Well-Known Member
Here's the article abstract with the 13:40 thing.
Shorter photoperiod cause early flowering, restricting yields in Industrial hemp (Cannabis sativa L.). Trials were conducted under different light regimes under the protected structure in Bundaberg, QLD, Australia. Little difference was observed in plant maturity when photoperiod was at or below 13 h 40 min but was significantly delayed when photoperiods exceeded 14 h 40 min. Plant heights at harvest increased significantly with extended light. Plant heights at harvest were 1,188 mm and 1,161 mm for natural light treatments, 1,286 mm in treatment 3 (13 h and 40 min light period) and 1,395 mm in treatment 4 (14 h and 40 min). Stem thickness increased, whereas stem and root yields at final harvest were greater with extended photoperiod.

A parallel field trial as separate experiment was also planted at the same location over five consecutive dates (PD1- September 15, October 25, November 25, December 16, and January 23), which showed that November 25 as an optimum timing as evidenced by highest plant height and dry matter yield compared to other planting dates. Results from these trials clearly indicated that day length must exceed at least 13 h and 40 min during the growing season to produce high yielding hemp for the tested variety.

page
 

BobCajun

Well-Known Member
I found another hemp article after my last post and it seemed to show that 13.5 hours was optimal, at least for the four varieties they tested. Don't know where the article is now, apparently didn't save it. So anyway that's what I have the timers set to now, see how that turns out. 13:40 did seem a little long really and just a weird number. 13.5 simplifies things and probably works even better from the curves shown in the article. The top of the curve was always right around 13.5. I think they mean from seed, I don't know, but maybe it also is best for clone plants. Certainly should produce more weight than 12 or even 13, just have to see if it causes any negative effects, like loose buds or something. With 13 I got more solid buds than with 12 though, so maybe they'll be even more solid.
 

pop22

Well-Known Member
These alternate light schedules have been debunked and are a waste of time and effort. You can't get more from less, it defies the laws of physics. X number of hours of light will give you x amount of bud. Finding the plants flowering trigger point for the strain makes more sense as some will flower just fine with up to 14 hours of light.
 
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