No plant, not even on hydroponic table, can grow during night. Its status is listed as: "not growing (resting)".
Sunlamp consumes 600 W of power, second highest after Smelter which eats 700 W.
Sunlamp doesn't turn off automatically at night. Colonists aren't smart enough to do that. Such a waste of batteries.
sunlamp is for indoor growing not nighttime growing, plants do not grow at night. Gonna have to do it manually for now. Or make your power production better.
I've been annoyed by this too. There is no purpose to having sunlamps on during nighttime so having them turn off automatically instead of hogging energy would be nice.
I don't know why lit plants don't grow at night, didn't they in previous versions?
Well in terms of biology plants don't "rest" at night, they perform light independent reactions which are essential to their growth.
-Argon