Use for outsized pumice

I have quite a bit of too large or too small pumice (dust) after sifting for potting. Wondering if there is any use for it other than put in compost, which I assume would be OK?
Thanks for input.

you could use it as a head bed medium for repotting recovery. i use mine over a propagation heat mat, with a wood frame (2x4s) to hold the pumice. the fines, you can use as a cutting medium, either on its own or mixed in to your potting soil.

that’s where mine ends up and it seems to work. the larger size is also used for aeration layer (pumice, lava, and akadama).

the side of my shed would make Howard Hughes jealous with buckets and bags of this and that in different sizes.!

If by compost you mean a municipal compost, they sometimes don’t like soil components in the mix. I know my current one doesn’t want stuff like pumice to be added to the bin.

Anyway, I usually mix the stuff that is too big into my vegetable bed. I keep the fines in a tub for later use like sand.

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Ha! Mine is starting to look like that, also! Thanks. The large pumice I get is larger than aeration size. I wonder if there is a source that is better for the potting and aeration sizes 1/16 to 1/2 so there wouldn’t be so much left over?

Great! I have my garden compost bin. Glad to know it can be used in potting as sand.

Pumice is relatively easy to crush. I have used a sand tamper with the pumice on a concrete floor inside a large simple frame to keep it from flying across the room. Not very fast, but it is an option.

Yes…I have stepped on it and tracked it all over! I guess there would be no way to control the size, would there?

No, best you can do is hit it a minimal amount of times to keep it from turning to dust.

I hit it enough to break up the big particles, sieved it, and then recrushed the big ones. I am thinking of getting/making a roller style grain mill. May need to make it to get the size range I want.

Marty, maybe you could make one similar to the clay rollers that potters use. This can be adjusted for height etc. Just a thought…

@Keith-in-UK that is my idea, but with the rollers side-by-side so the pumice and other oversized material has to pass between them .

Maybe you can buy an old mangle and adapt that as they are also adjustable, probably quite cheap to do as well.