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

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

How many hours of light do I need for cannabis 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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  • zhuk
  • 5.00 star(s)
Great info. I'm just amassing the bits & pieces needed to start growing and was wondering about how to combat heat in summer (in my case australia, and it gets hot! and will do in my intended grow area, esp as summer will be well on the way by December) So the lights off at the hottest times makes great sense ;)
  • Frankster
  • 5.00 star(s)
That said, I do 24 hours with it's really cool parts of the year, and can use the extra heating in the house, and warmth for the plants. I agree 18/6 has it's advantages. Would be cool to see one on this regarding flowering, and techniques to speed the ripening process along in some situations.
  • Hez
  • 5.00 star(s)
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
  • 5.00 star(s)
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.
  • 5.00 star(s)
good advice
  • Flip3387
  • 5.00 star(s)
Not common sense to a beginner, answered my question.
  • hamphealth
  • 5.00 star(s)
Convinced me.
  • MrBulldops
  • 5.00 star(s)
That is a common sense answer!
  • burn4me
  • 5.00 star(s)
perfect explanation
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