"Dwight Lassiter" wrote in message
...

I buy Perlite and Peat Moss to my black much also. The all organic
stuff deteriorate so quickly that a level 5 gallon pot will sink 4
inches in a season.
If I had a choice between the two, pick Perlite. The peat will
deteriorate also - the perlite will not.
Jim in So. Calif.

Yes, that's what I assumed. Even the peat moss will eventually
decompose, though the stuff is fibrous enough that some structure may
remain. I just want some mix that will retain permeability for a few
seasons. Certainly true that perlite (or charcoal) should help with
that.

Support structure aside, Perlite is pH neutral, charcoal pH will vary
depending, but mostly it will be alkaline.
Just be aware of what the specific addition will do to the soil chemistry
and factor in your hard water usage.