logic

How many hours of light do I need for veg growth?

18/6 or 24/0, that is the eternal question.

Those numbers refer to the amount of light and dark that the plant receives (18 hours of light / 6 hours of darkness). Anything above 14 hours of light per day will keep the plant in vegetative mode-- growing leaves and not buds. When you want to switch to flowering you reduce the cycle to 12/12.

Cannabis plants grow without hassle under 24 hours of continuous light. There has been no controlled recordings of increased hermaphroditism or problems-- most growers now use the full 24/0 cycle.

However, 18/6 does have it's advantages:
  • Reduced electricity costs. When you have a good mother plant collection and clone cycle, you don't need the increased growth the extra light provides. Lowering the cycle will save money.
  • Allows the equipment and room to cool down. Those 6 hours of darkness can be timed to happen during the hottest part of the day, providing some relief for growers in hot climates.
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Hez
I keep mine on 24. What I use are the low watt (13) / 100 watt output "green energy" bulbs. Keeps my meter from spinning like a Frisbee on meth. Three bulbs seems to be more than enough light in a 10X10 room. Bonus is the bulbs have a 10 year life according to the package and guaranteed.
angeltrumpet
This is answer my question, I have my one seed under 18 hours light since 25th January, it is just coming to the 3rd set of leave,roots appearing through bottom of pot.I think to transplant to a bigger pot in a week , I want to delay flowering till its hopefully a dwarf conifer size and bushy, then take outside gradually increasing the natural sunlight hours knowing that it starts to flower, as I read on countless forums. This is my
first time with lights using a 50watt Led.
Frankster
Yea, helps with peak hours for sure.
D
good advice
Flip3387
Not common sense to a beginner, answered my question.
hamphealth
Convinced me.
MrBulldops
That is a common sense answer!
burn4me
perfect explanation
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