Is nursery grown pot mediums all over the map.....everything from peat to sand ?

I've never bought a 1--->7G or anything where native soil or sand was the potting medium

Field grow BB yes. But container stuff , no.

All the JM's I've acquired in pots (not B&B) have generally been composted bark medium of some sorts...

Went to a grower recently and granted it did rain heavy 2 days prior, the pots, for a 1-2G were heavy as heck. All his potting medium seemed to be loamy sand - I did find small traces of bark and maybe if I looked under a microscope , maybe some pumice in the mix if I looked for it after unpotting and root washng it. If I was guessing man, it was his native soil being used . Just short of the large speciment pieces which one could clearly tell was sourced elsewhere.....as a whole, was super disappointed in the entire nursery crop there. Said nursery had top reviews....and I drove 4 1/2 hrs there so wasn't leaving empty handed with the cultivar I seeked. The root system was crap and just the crop being sold....the online places of JM I've been getting has better root system, branching, leader size and health. Should have just stayed home and not make the trip. Even had a trailer on the hitch as I thought I was coming home with more JM's - instead it was just the single cultivar I seeked.

So have you guys encountered similar where you arrived at a nursery/grower and said what heck on the potting medium