Katrina, I am mixing my own soil medium from granite gravel, bark nuggets and pumice, hence I fertilize. That's my reason. If the plants look good and are pupping I think that's pretty good indication not to fertilize as they don't seem to need it, IMO. I think Sans are not heavy feeders, someone will correct that if I'm wrong, hopefully.

It was recommended to me by an amazing grower that Osmocote is a great way to go with sans as it is a slow release fertilizer. I've fertilized all mine with that. And bone meal. And coffee grinds.

They were using Osmocote at the nursery this morning. All the plants have those lil pellets.

I have been usng Osmocote for a long time. It's so easy.