I grow daylilies in boxes. Because I'm beachside, we get a lot of salt in the air so the only type of marker that lasts for me are the Kincaid stainless plant markers. They are reusable and when they get nasty from removing multiple labels, then I attach new faces plates I've purchased. With the p-touch label, these plant markers stay legible for a long time.
I also keep maps of each of the 6 boxes on my computer. Lately, I've been using new maps with colored daylily pictures (instead of names) so that I can see what the box will look like when I get done transplanting the daylilies. Time consuming but much easier than making a big OOPS!! during the planting process. Down here, I will start around Nov. 1 and try to get everything done before Thanksgiving.