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.

Gardening Under Lights Book

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