Absolutely. I shake it around a bit over a piece of bug screen stapled onto a frame, just to remove the dustiest bits. If, however, the gritty mix has been in use for over 4 years, I wash it, put it in my (surprise!) hypertufa trough that I made for this purpose and just leave the stuff exposed outdoors for a year. I'd occasionally hose it, basically allowing it to fallow, as it were. I sift it before I reuse it though.

All this is assuming you are not repotting because of disease in the first place.

Pagan

AJ, Personally I would not reuse any mix that would contain organic material, what is left on the roots is already partially decaying. Adding new mix will not slow the decaying process, only complicate things in the future. As you mentioned there may be a problem with diseases and insect eggs in the old soil.

That being said, I use a mix of pumice, #2 cherrystone and zeolite. I will reuse this mix because it can be cleaned (sterilized). I will soak overnight in a bleach solution, Physan 20, povidone iodine, or even hydrogen peroxide (H2O2).

Good luck, Joe

Thanks for the replies and help offered.

No disease as far as I know. Just repotting. Mix has only been used for ~5 months in direct sun. Organic matter is only pine fines and a little bit of coir. These are also small <18" tall and ~13 months old. I guess I'll inspect the mix and react accordingly.