For anyone growing seedlings indoors under lights during the winter who would like to give their seedlings long days but not keep the lights on for 16 hours a day then one can give the seedlings a day extension or a night break and produce the same effect. To do that one would usually use 60 watt incandescent light bulbs and either turn them on for a few hours beginning just before the other lights switch off (day extension) or that turn on in the middle of the night for four hours (night interruption). Incandescent bulbs are used because they produce more light with the correct characteristics to trick the plants into experiencing long day lengths. Long day lengths reduce or prevent at least some growth rests. They probably will not prevent all growth rests as it appears that some seedlings take rests no matter what the growing conditions.
