18 or 28 hour day ???

[rodekyll]

when you say "day" do you mean the light portion of the cycle or the entire light + dark time? In other words, do you intend to retain the circadian (light + dark = 24) "day", or do you intend an ahemeral (light + dark = non-24-hour) "day"?

[rodekyll]

If it's a circadian day, I'd go with lip's 18/6, based on the plant's tendency to both aspire and respire. With sunlight it takes in co2 and expells o2. At night it reverses and takes up o2, expelling co2. I've monitored this behavior with my co2 meter, and backed up my observations with some research (yes, I googled it). During the light cycle co2 levels go down around 300ppm in my grow room. during the dark cycle they rise to as much as 800ppm. The literature confirms it.

[the image reaper]

using 24 hours of light per day will keep the plant alive and growing, usually no obvious problems, .. BUT ... the plant needs the dark hours, thats actually when they do the most growing, and processing of their nutrients ... plants tend to show males more under long light periods ...if you want to use 24, go ahead, theyre your plants, just dont whine when you find your herb doesnt measure up ... the 24 hour plants will not grow measurably better, anyway ... :smokin:

[LIP]

It's been tested more than once, and with the 6 hour dark period it does grow faster. The only time you should have it on 24/7 is the first 1 or 2 weeks.

Then the plant's cells react better to having a dark cycle and it makes more energy and puts it all in to the plant during the light cycle.

It's like charging the plant up ready to make new growth.

[Jerrodg]

I have no scientific backing on this, only observation from my first grow. When starting the seeds, they were on an 18-6. I took a group of clones (only one survived) and put it under 23-1 when I switched the main plants to flower. That bastard is growing twice as fast as the originals, although conditions are slightly different that may contribute to that. So, fwiw 23-1 is working well for me, but could be a variety of different reasons.

[turtle420]

I'd like to get some of those 28 hour days...

"18 or 28 hour day ??? "

[Sinsemilla Jones]

But I think that was on Coast To Coast AM.

[postmandave]

Thanks for that lip. knowledge is everything. Thank you.the postman.

[turtle420]

It's been tested more than once,

Sorry LIP, but I've got to disagree...

I think this has been "opinionated" more than once...

I've yet to see pictures/documents/files/threads/posts actually showing the difference between 24/0 and 18/6.

I've seen various experienced growers, suggesting 24/0.

I've also seen various experienced growers, suggesting 18/6.

In the end, it's just, a decision up to you... this hobby is great!

[kingkewl]

18/6 ... I'm using now.. and 12/12 in flower.. but, I'm talking a "shorter day/night"... I really don't think the plant is useing every minute of light dark it's getting..I have seen alot faster growth on 18/6 then 24/0.....
I want to shorten the 24 hours down to 20 or 18...ie:vegin on a 15/5 and flower under 10/10....get it now?

let's see how fast the little suckers can grow...lol