I never buy less then 3 yards of any fabric that I really like and don't have a plan for it yet. The reason why is, when I finally decide on what I will use it for I want to be sure I have enough. I rarely use more then 3 yards in any one quilt but there has been times when 3 yards just barely made it.
Also I want you newbies to understand that if you really find a piece of fabric you truly love, you better grab it and make sure you get plenty because it doesn't last long on the shelves if it's that pretty and they don't make it all the time so chances are when you do go to make that quilt, you will not be able to find that same piece later on. This has happened to me a couple of times. I guess that's why 3 yards is now my minimum amount.