Believe it or not, plants need darkness at night. Lower temperatures combined with shortening days (longer nights) signal some plants to bloom and other plants that its time for a well deserved rest. In spring, lengthening days (shortening nights) and warmer temps tell them its time to wake up.
Don't deprive your plants of darkness. Instead, adjust your timers to give them long summer days and shorter winter nights. They will thank you for it.
