Print article We are just about in March and the light is coming back at a faster pace. Darkness after 6 — I could play with that and get a good movie title. And it is getting lighter by minutes every day. This time of year, if you keep your plants in a sun room, you may need to provide ventilation on sunny days or you risk cooking them. As much as I keep yelling about the need for plant lights during the dark months, there is nothing like the impact of the return of the sun to demonstrate how well plants respond to light.