I use a Brother P-Touch with white tape. So far nothing had faded and I've been using it for about 5 years. You can change the font size for those really long names! The last time I ordered pots from CalWest I also ordered 100 plain white tags.
Forgot about this thread. Handwritten labels written with Sharpies fade. For something permanent, use a paint pen (available in art supply stores). I use:
DecoColor fine line 'Opaque paint marker'
Brand name is Marvy
Sold by Uchida of America Corp., Torrance, CA