Re-use Aluminum siding.
 

I'm about to remove the aluminum siding from my newly-purchased house
and, pretty much simultaneously, create a new vegetable garden. Rather
than toss all the old siding and buy and treat new wood for the raised
beds, is it possible to use the siding as raised bed structures.
Possibly doubling up the runs for increassed rigidity?

Cx

That is what I did with 3 of my old beds. It lasts forever, of course,
but here are some disadvantages. First, I did not bury the bottom, but
you should. That way grass rhizomes will not be able to push in and
invade the beds. I suggest burying them 3 inches.

Second, I was going to use no-till in my garden, and it works very
well, except that clearing radicchios and their immense taproots takes
a lot of digging. With sides that are not so rigid, they bend outward a
bit more every year. Third, when I come in with my wheelbarrow full of
manure and I dump it into a bed I will occasionally bend a side. The
last two problems can be minimized with double runs, as you say, and
also by planting stakes on the outside. I used old piping to make the
stakes. They help, but I did not put enough of them, and of course they
catch the hose all too often. All in all these are fairly minor
problems, go ahead and reuse that siding.