aem wrote:

We're using huge rolling pots on our deck
these days and we toss the "used" potting soil into the composter after
the growing season and start fresh next year, but he's always been picky
about changing what's grown where the previous season when we gardened
directly in the soil. He rotated things around each year which is
apparently important so that the nutrients aren't depleted and certain
plant diseases are avoided

Yes, rotation is very good practice, though if you're changing potting
soil it wouldn't seem to apply. -aem

I worded that badly. When we had an actual garden in the yard, he
rotated things. Our largest was 40'x40' but we were a lot younger then!
We're just doing pots in this house as the backyard is so shaded that
the areas of sun are just not where I want to plant. The deck pots work
pretty well. I'd love to explore growing things in a small greenhouse in
our mild winters, with lights if necessary.