24 hours compared to 18 hours

merahoon

Well-Known Member
I'm curious to what different growers do and their experience with different light schedules for the veg period. Has anyone noticed a difference from running 24 hours of light to 18 hours of light to 6 hours of darkness? Open for debate.
 

2x2lcallingcq

Active Member
I grew my whole veg 24/7 until they were lush enough to flower then i went to 12/12 now I am finishing in a week so I am at 16off/8on
 

merahoon

Well-Known Member
I wonder if the plant does different things while its sleeping compared to when its awake. Is there scientific reasoning that 18/6 is better?
 

weedyoo

Well-Known Member
I wonder if the plant does different things while its sleeping compared to when its awake. Is there scientific reasoning that 18/6 is better?
their are so many things that ccan make your grow good and o am finding out alot has to do with how many days and nights you can get

my veg cycle 18/6
my bud cycle 6/12
 

GlassFreak

Well-Known Member
I wonder if the plant does different things while its sleeping compared to when its awake. Is there scientific reasoning that 18/6 is better?
ive heard 24 all the way through veg causes a delay when going into flowering but after the week or so of slow growth it should just blow up with growth.
i personaly like 18/6 more because there is more general plant growth.

scientificly---- the plant under ground (roots) concentrate growth durring the day or light cycle, while the plant above ground concentrates on growth durring its night or dark cycle. plants need the dark cycle to grow to its full potential durring veg, 24 actualy kinda keeps it shorter till flower. in the end im thinking it evens out, with the explosion of growth durring flowering for 24 and the more consistantsy of the growth with 18/6 and no delay in growth i would at least hope the results are close.
 

merahoon

Well-Known Member
6/12?? Hmm I've never heard that before. Have you tried a complete cycle running those hours?
 

GlassFreak

Well-Known Member
what its doing is storing all the energy it makes durring the light cycle in its roots by making more roots, when the lights go off this energy is suposed to be used to grow the plant, if no dark cycle comes it just stores up more and more energy without giving much to the plant, but as soon as the lights go off for 12 hours and on for 12 hours it starts to pump all that energy to the plant growth, with 18/6 it gives the plant more energy, more spread out throughout the life cycle.
 

tokinman

Well-Known Member
unelss you are using fem seeds, 18-6 will give you more females.. 24-0 will give you more males.. reason enuf there imo to do 18-6.
 

GlassFreak

Well-Known Member
actually if you give your plants one less hour of light in the 18/6 shcedual (17/7) it greatly increases the odds of getting females.
 

merahoon

Well-Known Member
Sounds like you could go either way and in the end you would achieve very similar results. Now I wonder if running 24 hours during veg would make your buds in the end a little more fluffy. I only say this because the explosion of growth would cause the plant to stretch somewhat while the buds are filling in. Instead of them clumping together in one spot, they are pulling away from each other during that period. Would you agree?
 

atombomb

Well-Known Member
Nothing makes you have any more males or females then LUCK. The lights dont mean shit. The less light you give during the flowering stage the shittier your buds are going to be when they are done. And the longer it will take them to finish.

No here say please!!
 

GlassFreak

Well-Known Member
Info on "Feminized Seeds"
In an experiment done in 1999 we grew 15 varieties of "feminized" seeds. We started with 30 seeds per variety. The goals were: 1) to determine the percentages of female, male, and hermaphroditic plants. 2) to compare the uniformity (homogeneity) among plants from "feminized" seeds with those grown from "regular" seeds. 1. The results were excellent. Nine out of fifteen varieties had 100% female offspring. Percentages of female plants from the other 6 varieties were between 80 and 90%. These plants were all hermaphrodites, producing their male flowers at the end of their lifecycle. Seed-setting hardly took place. No males were found. 2. Approximately 70% of the plants of varieties grown from "feminized" seeds were far more uniform than plants grown from "regular" seeds of the same variety. About 20% of the varieties were a little more uniform, while in 10% of the varieties no difference in uniformity was seen. From literature and our own findings it appears that the growth of a male or female plant from seed, except for the predisposition in the gender chromosomes, also depends on various environmental factors. The environmental factors that influence gender are: a higher nitrogen concentration will give more females. a higher potassium concentration will give more males. a higher humidity will give more females. a lower temperature will give more females. more blue light will give more females. Fewer hours of light will give more females. It is important to start these changes at the three-pairs-of-leaves stage and continue for two or three weeks, before reverting to standard conditions. To produce our feminized seeds, we start with selected female clones. Under standard conditions these female clones do not produce any male flowers. By the method we found, we are able to have these female clones produce abundant male flowers and pollen. The pollen thus produced we use for the production of our "feminized" seeds
 

Nocturn3

Well-Known Member
I've heard that 20/4 is the optimum vegging time, at least for sativa dominant strains (probably the same for indica as well).

Oldtimer1, who is well known in the growing world, and knows his stuff pretty well, made the following post on the subject:

We did a lot of experiments with light times a few years back using known sat and sat dom clone lines.

With Vegging ie under hid lights.

20/4 produced the most sturdy growth and the most bulk. Best final yield, taken as 100%.
22/2 Less of both. yield 88%
18/6 Studier than 22/2 but slightly less bulk. yield 87%
24/0 Much lighter in all aspects than 18/6. Yield 79%
16/8 The weediest plants. yield 67%

Plants vegged to final pots under fluorescents at 20w per sq ft on 18/6 yield 49%

Have not tried 36 hrs dark but did try 48 hrs from 18/6 veg. The final yield was down between 15 and 20% by var the pure sats the biggest loss in final weight and caused the odd herm, [sats] it did reduce the flowering time by 5 to 8 days.

For the mum lines we have 20/4 to 12/12 gives the best crop weight and bud quality, really thats all I’m interested in.
Taken from here.
 
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