I see lots of discussions about the ratio of light to dark within a 24 hour cycle. Has anyone experimented with extending or contracting the cycle? What would be the effect of doing a 24 hour light/12 hour dark cycle, or running a 6 hour on/6hour off period? What would be the effect of having day being 23 hours or 30 hours instead of 24 hours?
What is the effect of a day which is not 24 hours?
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I have thought about this and came to the conclution that 12/12 is best due to "equality" of plant needs.
This thread is a great bit of info:
Do Roots Really Grow In The Dark?
A quote from the post:
So in my opinion, If a plant is given uneven quantities of light/dark then it will either over charge its "batteries" or undercharge them. This is just an general theory not the gospel but it seems to make sense to me.
Just my 2 cents.
Jonny
This thread is a great bit of info:
Do Roots Really Grow In The Dark?
A quote from the post:
So in my opinion, If a plant is given uneven quantities of light/dark then it will either over charge its "batteries" or undercharge them. This is just an general theory not the gospel but it seems to make sense to me.
Just my 2 cents.
Jonny
I'm a believer in consistency for this amazing plant. When they get into their routine they grow at a very explosive rate and have excellent hauls.
When things like light are erratic, it confuses the plant resulting in stalled growth, mutations, and even hermies in some cases.
Cannabis likes every day to be the same as the previous day. Keep the lighting consistent with the only major change going from veg to bloom and you'll be rewarded.
When things like light are erratic, it confuses the plant resulting in stalled growth, mutations, and even hermies in some cases.
Cannabis likes every day to be the same as the previous day. Keep the lighting consistent with the only major change going from veg to bloom and you'll be rewarded.
"Under constant environmental conditions, such as can be maintained only in a laboratory, the period of the circadian rhythm is free-running - that is, its natural period (usually between 21 and 27 hours) does not have to be reset at each cycle. It behaves as a self-sustained oscillator." (Raven, Evert, and Eichhorn - Biology of Plants 7th ed.)
The rest of this is anecdotal so take it with a grain of salt. A friend recently tried something similar in a commercial setting using an 18-hour day. 12 hours of daylight with 6 of night provided the 18-hour cycle. The main differences between this and traditional light scheduling were that plants tended to grow in small spurts as opposed to slow, steady growth. Stranger growth patterns were observed in strains with less genetic stability though no signs of sex change before harvest.
This was conducted without a control group in a typical sterile, commercial environment. 15,000 watts on light rails (hps the whole grow), 120,000btu AC @ 78F with ample airflow, flood trays w/ 6" rockwool using Humboldt Nutrients 3-part (edit: not the full schedule, just the base + other supplements). No added CO2.
All in all it didn't provide any noticeable benefit in yield and made maintenance tricky since daylight hours were never the same. It hasn't been attempted since and for all we know could cause problems in a less dialed-in environment so its up to you.
Personally I think there is an advantage to be had from altering the day cycle, but circadian rhythm in all organisms is still mysterious. I read a paper a few days ago about the confirmation of circadian rhythms in red blood cells. Previously that was thought impossible since red blood cells don't have DNA (read: a gene to control day/night cycles). IMO try it and see what happens!
The rest of this is anecdotal so take it with a grain of salt. A friend recently tried something similar in a commercial setting using an 18-hour day. 12 hours of daylight with 6 of night provided the 18-hour cycle. The main differences between this and traditional light scheduling were that plants tended to grow in small spurts as opposed to slow, steady growth. Stranger growth patterns were observed in strains with less genetic stability though no signs of sex change before harvest.
This was conducted without a control group in a typical sterile, commercial environment. 15,000 watts on light rails (hps the whole grow), 120,000btu AC @ 78F with ample airflow, flood trays w/ 6" rockwool using Humboldt Nutrients 3-part (edit: not the full schedule, just the base + other supplements). No added CO2.
All in all it didn't provide any noticeable benefit in yield and made maintenance tricky since daylight hours were never the same. It hasn't been attempted since and for all we know could cause problems in a less dialed-in environment so its up to you.
Personally I think there is an advantage to be had from altering the day cycle, but circadian rhythm in all organisms is still mysterious. I read a paper a few days ago about the confirmation of circadian rhythms in red blood cells. Previously that was thought impossible since red blood cells don't have DNA (read: a gene to control day/night cycles). IMO try it and see what happens!
i ve tried 24/24. never seemed to bud. tried 6 on 6 off then repeat. i thought that may work but really never did anything. ive found that 12/12 always worked best. go from summer to fall. real basic. i do 20/4, then 18/6 then 12/12 now no funking around. at the end,during flushing, go to 11 on 13 off. 24 off w/ a dehumidifier, then 11/13 until 80% amber.i always veg for 10 weeks minimum. veg'd the wonder womans starting thanksgiving.
looking at 4z's a piece min.
2 more weeks on the wonder womans and 4 on the MK. W.W. is starting to amber
MK is such an awesome plant but a long flower time.10 to 11 weeks. just 12 and 12 as long as i can.
i got too much of nothing to do, and im very busy at it.
McCrackin
New Member
I play in the 1130 dark / 1230 light cycle... Also get a strong bud response and it usually means it is hard to screw up.
For example plants can bud right now that are outside... This shouldn't be happening if light times are the determining factor... The days are getting longer. It is a hormone that raises when the plant is in the dark that keeps these types of plants flowering... So a manual long 15+ dark period every few days, keeps the hormone up enough to bud.
Autoflower is simply f1 phenotype that have been bread to increase this specific hormone faster than usual in dark periods. The hormone vanishes with almost any light brighter than the moon. In fact the moon decreases the hormone rise of plants when brightest.
So the balance of this hormone, the rate of how fast it builds up like lactic acid in the dark period compared to the amount of time in the light period without this hormone to effect regular plant function and the plants metabolic rate of excreting waste product and photoscent only while the light is on... Gets you the bud. Too much dark, your plant can get rid of waste and breathe, too much light and these plants can just continually breathe and that hormone stays down and you got a mother that's been in veg for years no sign of bud.
Tomatoes cannot go in 24 hour light, nightshade need the dark cycle to rest the plant's engine.
This explains the 6 hours never budding. 6 hours is not long enough to get the plant to build up enough hormone to have the flower response.
The post above is wrong about required dark for cannabis it does not require the rest to grow veg. But the plant needs to excrete waste and can only do this in light during photosynthesis. Too much dark means a buildup of that hormone and others. Too much dark plants gas out.
So back to the posted topic...
You have to measure the hormone rise rate, the gas or asxia buildup, know the max toxicity before plant gases out, then you could flip on the lights at stress peak...
Because the plants are from earth, where a 24 hour day is the timeframe for the sun these types of plants all have a natural equilibrium focusing towards 12/12, along the equator where cannabis started out...
Now from here plant to plant everyone is different with a natural occurring median at 12/12 for flowering.
If a plant is bred to build that hormone at a faster rate, without toxins building up as fast... Defined auto flower .
If you determine that the plant strain only needs 10 hours dark to buildup enough hormone to have strong bud response, adding those two hours to the day cycle might not be the best thing. In this case adding the two extra hours of light allowed the plant enough time to fully excrete all waste .... I call this monkey bud.
Light intensity has everything to do with the process after that...
M2€
For example plants can bud right now that are outside... This shouldn't be happening if light times are the determining factor... The days are getting longer. It is a hormone that raises when the plant is in the dark that keeps these types of plants flowering... So a manual long 15+ dark period every few days, keeps the hormone up enough to bud.
Autoflower is simply f1 phenotype that have been bread to increase this specific hormone faster than usual in dark periods. The hormone vanishes with almost any light brighter than the moon. In fact the moon decreases the hormone rise of plants when brightest.
So the balance of this hormone, the rate of how fast it builds up like lactic acid in the dark period compared to the amount of time in the light period without this hormone to effect regular plant function and the plants metabolic rate of excreting waste product and photoscent only while the light is on... Gets you the bud. Too much dark, your plant can get rid of waste and breathe, too much light and these plants can just continually breathe and that hormone stays down and you got a mother that's been in veg for years no sign of bud.
Tomatoes cannot go in 24 hour light, nightshade need the dark cycle to rest the plant's engine.
This explains the 6 hours never budding. 6 hours is not long enough to get the plant to build up enough hormone to have the flower response.
The post above is wrong about required dark for cannabis it does not require the rest to grow veg. But the plant needs to excrete waste and can only do this in light during photosynthesis. Too much dark means a buildup of that hormone and others. Too much dark plants gas out.
So back to the posted topic...
You have to measure the hormone rise rate, the gas or asxia buildup, know the max toxicity before plant gases out, then you could flip on the lights at stress peak...
Because the plants are from earth, where a 24 hour day is the timeframe for the sun these types of plants all have a natural equilibrium focusing towards 12/12, along the equator where cannabis started out...
Now from here plant to plant everyone is different with a natural occurring median at 12/12 for flowering.
If a plant is bred to build that hormone at a faster rate, without toxins building up as fast... Defined auto flower .
If you determine that the plant strain only needs 10 hours dark to buildup enough hormone to have strong bud response, adding those two hours to the day cycle might not be the best thing. In this case adding the two extra hours of light allowed the plant enough time to fully excrete all waste .... I call this monkey bud.
Light intensity has everything to do with the process after that...
M2€
too old
New Member
My calcs may be wrong too, but this is what I came up with:
0.0014 ms X 1(day) X 365 (roughly one year) X 100 (years in c.) X 50 (# of c's) = 255.5 seconds in 5000 yrs.
2555 secs/ 60 = 42.58 mins./ 60 = 0.709 hrs
But all this means nothing, no one kept track. Rotational rate changes constantly as we saw with the quake in Japan.
0.0014 ms X 1(day) X 365 (roughly one year) X 100 (years in c.) X 50 (# of c's) = 255.5 seconds in 5000 yrs.
2555 secs/ 60 = 42.58 mins./ 60 = 0.709 hrs
But all this means nothing, no one kept track. Rotational rate changes constantly as we saw with the quake in Japan.
it means absolutly nothing. because sunlight doesn't care about time. it will always be like that.
correct, but i think you miss understand.
im talking about classic darwinian evolution, at some point in history, there was no disticntion between indica/sativa/ruderalis. its was a common genome. its no different to black people evolving into white people because we moved geographical area.
Ruderalis came to be, as a result of its new growing conditions.
lmao i think we are both right, we are just arguing different points.
im not talking about when 9time e.t.c) im talking about where!
on the equator a seed that germs here can pretty much expect 12/12
however, should the same seed be blown to the north pole and by one of those miracles of nature called evolution, survive and grow. it would NOT expect a consistent 12/12 with strong lumins. the light is weaker there and the plant could experience a night that is months long.
to re use my human analogy, the guy that moved to europe didnt go to sleep one day and suddenly he woke up white...the passage of time (in the new enviroment) caused minute mutations over successive generations. simply because he was no longer in his default habitat.
im not talking about when 9time e.t.c) im talking about where!
on the equator a seed that germs here can pretty much expect 12/12
however, should the same seed be blown to the north pole and by one of those miracles of nature called evolution, survive and grow. it would NOT expect a consistent 12/12 with strong lumins. the light is weaker there and the plant could experience a night that is months long.
to re use my human analogy, the guy that moved to europe didnt go to sleep one day and suddenly he woke up white...the passage of time (in the new enviroment) caused minute mutations over successive generations. simply because he was no longer in his default habitat.
i got some cotton candy. actually its nirvana bubblious. its very good on the indica side. no motivation and slow down weed. good for night. good for pain.
growing ice plant now by nirvana. and just harvested a papaya plant mostly indica.
ice is 50/50 sativa and indica. i need a good sativa for the morning.
i need more sativa.
growing ice plant now by nirvana. and just harvested a papaya plant mostly indica.
ice is 50/50 sativa and indica. i need a good sativa for the morning.
i need more sativa.
aww man, i saw this documentary that pretty much explained our pre historic relationship with weed (our ancestors were involved with cannabinols before we even left the sea)
if you think of THC as a key, a very complicated take a thief a decade to try and replicate key. there is a certain part of our physical brain that is considered a lock that is a perfect fit. the odds of this happening by accident are astrinomical. we humans have practically been bred to recieve the benefits of THC. =)
