Intermittent darkness

Is it all right to turn the lights off for 30 minutes during the 18-hour light period in the vegetative stage? I want to let the room cool off a bit. Will it make the plants flower?
C WeeD,

Marijuana plants flower based on the number of hours of uninterrupted darkness they receive. Only when the plants experience a critical period of about 12 hours of darkness for several consecutive nights will they change from growing vegetatively and start flowering. An off period of half an hour or even six hours will not hurt them.

Why is the light off for six hours during the vegetative cycle? Vegetatively growing plants need no dark period. Since growth is based on total light suitable for photosynthesis, turning the light off six hours a days slows growth by about 25%. Growing with the light on continuously increases yield and shortens the vegetative growth period, so it speeds up the crop cycle.

The light could still be turned off intermittently when necessary to keep the garden cool.

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