Less is always more.
You can never start packing for college too early.
Regardless of when you start, you're still going to be buying things last minute. Prior to college, it's good to clean out any items you no longer use. This way, when you come home for the summer, it's easier to make room for your new college items. Surprisingly, you need a lot less than you think at college. The biggest mistake you can make is bringing too much stuff.