I've been sprouting some broccoli seeds this week (it's my first time, I'm using the jar/cloth method), and I'm having just one problem. Maybe 1/2 to 3/4 of the seeds have sprouted so far and are fairly long, some of them are just starting and some haven't even sprouted at all. If it was just a few, I wouldn't be worried, but there are a lot of them that haven't sprouted. Could I be doing something wrong? Could the seeds just be bad?