Lowes has bags of red lava rock as landscaping cover. Can that be used in large pots as part of the aerating medium? Light weight and readily available as opposed to pumice here in the north east. Large chunks and hard to break into smaller pieces.
I have a bag i bought a few years ago just sitting in the shed. I think i will put a tarp down and put the lava rock bag wrapped up in it . Then run over it a few times with my pickup.
I got a bag from tractor supply and tried to hammer them to small pieces. It’s much harder than I thought. So I just use the large pieces as mulch for my trees and mix the small pieces in potting mix.