Are My Plants Getting Sleepy?

[DieselDuds]

Iv noticed that near the end of there 18hr light cycle the plants leaves turn down a little bit . But after there nightly rest about a half hour after the lights are on they are back up and reaching towards the light. This normal?

 

[ChiefnJoeBlo]

Totally normal there just getting ready for bed.

 

[Bannacis]

They prepare for lights off and also prepare for lights on. After they have become accustom to their light schedule they will react accordingly, for lights off they will start to relax and let the fluids in its leaves and branches to return to the root base.
in a 6 hour lights off period they will start drawing up water about an hour or so before so they will be ready for the sun.
That is why it is important to keep perfect steady on/off times. if you change your times, they will require time to adjust.