I'm growing in soil. with germination they've been growing for 5 almost 6 weeks. Does it make sense to line the walls of my closet with tin foil. If so which side, the dull or shinny side.
Don't use tinfoil, pain it white, or get some mylar. Tinfoil can create hotspots and burn the plants....
Start the ferts now, a grow fert, until ready to flower, then switch to a bloom fert, but just read the directions.
I recommend Fox Farms, but there are a ton of things out there.
Start slow, and increase slowly. First sign of burn, cut them back. Take it easy at first!