Cannabis Grow Lighting Schedule

February 21, 2019

Getting cannabis to produce flower buds requires a strictly controlled lighting regimen. Cannabis sativa is a qualitative short-day plant. To remain in a vegetative state, plants require 16 to 18 hours of continuous light followed by 6 to 8 hours of uninterrupted darkness.

PC: Dan Heims

Once you are ready to force them to flower, reduce their daylength to 12 hours, followed by 12 hours of uninterrupted darkness, for about two weeks.

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