The logic is that is how the plants grow and work for speeding up the harvesting. They need the 12 hours of darkness, and of course some strains vary from that, but the normal is 12 hours of darkness they need to flower.
So you can't change the amount of darkness they get that makes them flower, but you need them to still go thru as many days of their normal flowering cycle, or at least the plant thinks it's going thru those many days(which it counts by dark periods), and the only way to do that is take hours away from the daylight time of flowering plants.
So you run a 20 hour day of 12 hours darkness and 8 hours of light, that saves you 4 hours each day, and every week making up 28 hours, or over one full day, so 6 1/2 weeks with a 20 hour day of flowering roughly and you can get a plant that takes 8 weeks to ripeness as if it went the full 8 weeks with a normal 24 hour light cycle. This is getting the heads to ripen, which is what gets us the different highs off the marijuana.
Now you have the speeded up flowering time for the buds with the high of flowering for 8 weeks in only 6 1/2 weeks, but those 4 hours that are missing from your light cycle will make smaller buds too remember.
Happy Growing
Alleycat |