doing a closet grow and was going to put tin foil on the walls all around the plant and i was wondering if that would help trap some heat inside the grow space since the room can get cold sometimes
no its not really a good heat retainer it cools down quickly but on the flip side when lights are on it does create heatspots which could burn your plants mate. if your having heating issues at night can you not put the heating on and if its controlled by thermostat just put it at around 18-20c,if possible???? but i would take your tin foil down asap,white emulsion paint just as good
Foil does trap (actually reflect) heat, it's designed for cooking for that very reason. It is not a great reflective surface for light, though. And it isn't a good insulator of a closet. If your room is cold you should add heat and/or put up insulation on the walls.