I save the small (3 oz) paper cups that I buy for taking medicines (because I got tired of washing glasses!) and use them for collecting seeds. They're great because you can write on them and they stack! Columbines really are pretty easy to keep an eye on; you just have to catch them before the pods get too dry and split. I just went out and tipped a few seeds off my dwarf Columbine. Heh heh, thanks for the reminder.