On 23 Apr 2007 22:18:38 -0700, Mike C wrote:

I am trying to make some Hypertufa outdoor planters. Perlite is hard
to come by except in small (expensive) bags. I found polystyrene
insulation at home improvement store. It looks like Perlite. I am
wondering if this would work.

No, it won't work with the prills you speak of. You can replace
perlite using sand. It can be lavasand or coarse builders sand.
Lavasand is red so the hypertuffa may have reddish appearance. Make
sure you put pegs in the botton to hold holes open for drainage.

On another note, if you want to use perlite, you can buy it in large
two cubic foot bales online, just do a search.