You will need to spray on a schedule. If you are spraying your plants right after the light goes off use a headlamp or a flashlight, you’re only changing your dark period by a few minutes. The plants will not react to such a minimal change, but you do not want to do this every day (a few times a week, tops). You might have heard that green light does not disturb your plants. Yes, your plant does not recognize green spectrum light, but ask yourself “does every green light only put out green spectrum light?” If it was a cheap green light, there’s most likely other spectrums bleeding through as well (not a whole lot, but enough to want to safeguard plants from too much exposure).