Josieskid - I use a slightly diff method skipping the PVC pipe. I write on 5" venetian blinds with special markers from Tractor Supply used to mark cow ear tags. These markers contain xylene, and this is what makes them permanent. Xylene was removed from all craft markers a few years ago. I totally bury the blinds when I plant, so just the very edge is visible. When the sdlgs bloom I can pull it up to see. Writing typically lasts years this way, and the markers don't get brittle from sun. Just another way of marking. I downsized my markers to 5" so I could be sure to get them all the way into the ground using a soil knife.
