If you ask stupid questions like this no one will answer you because you aren't willing to do the work of learning the absolute basics on your own and are expecting to be spoon fed. Before you start growing educate yourself better. It's pretty common knowledge that your roots have to be completely protected from light exposure. Just buy a few grow bags. Their $0.20 each and are light proof. I wash mine in the washing machine and reuse them. You can grow well and very cheap, but you have to know where to cut corners and where you just need to spend the money. If you can't afford a book about basic growing of marijuana(I got a great one for noobs for $40), then you can't afford to grow and are wasting your time.