I've started using high quality stainless steel straping I engrave the name or a designated # onto. It works great, no fading, cracking, blowing away, etc. They should last many many decades. The strapping also doubles as a handy tool for planting seedlings

Bummer. Wish I would have found this great site sooner!

Man o man great looking cactus!
If I wasn't a newcomer to the site I'd say send those open pollinated mystery seeds my way.