Composting

I have a happy worm bin that takes care of most of my composting needs. I use the castings around my garden, mostly when I'm planting something new, but I also feed my established plants with it when I can.

But! I've also been thinking it'd be great to deliver castings right into the ground, and would love to use semi-buried containers in the beds to compost right there. There are plenty of native composting worms in my location.

I have a bunch of small (1-1.5 liter ish?) buckets with lids that I'd love to repurpose for this. I was thinking I'd make a bunch of holes in the body and lid of the buckets, and bury them up to the rim. Then fill with some bedding and some scraps, and inoculate with come castings and some worms. And just feed whenever there's space, hoping the castings spread a bit into the ground, or otherwise dig it up when it's full of castings and bury it in a new spot.

My main concern is that the buckets would be too small. The reason I'm aiming for this size is honestly because I want to use these containers for something useful instead of tossing them out. I'd love any suggestions and to hear about your experiences with in-ground composting!