18 versus 24

McLuffin

Active Member
is there a significant difference between the two light cycles... someone told me there is, but im thinking electricity?
 

Hubert

Well-Known Member
is there a significant difference between the two light cycles... someone told me there is, but im thinking electricity?
I've noticed 24/0 is in fact faster than 18/6. That's not to say 18/6 is no good though, it does save energy...in fact I use 18/6 now istead of 24/0, but I'm not in any hurries.
 

Puff

Well-Known Member
According to the growers bible by Cervantes. In there is states that your plants will not flower until they have developed pre flowers. Usually 4-6 weeks into veg growth pre flowers show up. According to the book if you cut the light back to early the plant still has to produce pre flowers before it buds. "Always wait to induce flowering until after pre flowers appear. Inducing flowering with 12 hours of uninterrupted darkness and q12 hours of light before pre flowers develop will stress the plant. This could cause peculiar growth, and plants might develop into hermaphrodites. Inducing flowering before pre flowers will not expedite flowering. In fact, flowering will occur at about the same time as if you had waited for pre flowers to show! Plants grown from seed under 24/0 photoperiod will generally show pre flowers after plants that are given an 18/6 day/night photoperiod. Once pre flowers are distinguishable as male or female plants can be induced to flower with a 12/12 day/night photoperiod." It would seem that according to the growers bible its bad to stress your plants with 24/0. I just learned this recently. I used to go 24/0 but now I go 18/6.
 

Hubert

Well-Known Member
"Always wait to induce flowering until after pre flowers appear. Inducing flowering with 12 hours of uninterrupted darkness and q12 hours of light before pre flowers develop will stress the plant. This could cause peculiar growth, and plants might develop into hermaphrodites
I know that is straight outta the book but....I have to disagree. Due to room issues I've NEVER had a pre-flower on any of my plants. I've also never noticed any adverse effects to the plants. Pre-flowers can potentially take months, I usually see my first signs of sex within 2 weeks of 12/12.
 

cheetah2007

Well-Known Member
the first week to 10 days you can put the plant under 24/0 (i do that) and after that you can transplant into bigger pot and switch 18/6.i think the plant starts it's life better, but that's not proven......that's just my opinion man. Cheers!!! Cheetah
 

Mr Green Man

Well-Known Member
I am kinda new to this.

I have played around with both light cycles, when rooting clones.
I had read that 24/0 light was faster for this, but affter some testing, I found that my clones rooted much faster under 18/6. Later I did sone reaseach that and lernt that when the lights go out, the plant puts more enargy into growing down.

As I grow DWC, I can really see this effect. I will always grow 18/6 from now on.
But there are probably other facter too, like genitcs for a start.
 

FilthyFletch

Mr I Can Do That For Half
I prefer 24/0 over 18/6.I have done both over the years and have done side by sides. I find not only do the plants under 24 /0 light grow faster,bushier,and healtier in a lot less time but in the overall picture its cheaper to run them under 24/0 light as it cuts the veg time down signifigantly compared to the slower 18/6 which I find root growth is slower,plants tend to get more lanky and node growth is further spaced. I had converted to 24/0 light about 6 years agao and have never gone back.I also find that cloning powder is much better then cloning gels such as clonex. The side by side tests I did using same moms, lights rockwool and humidity domes had a result of gels succeding 75% of the time and powders with a 98% rate. I also have found powder clones root in 3-5 days while gels take 7-14 days
 
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