@LearnintoGrow
I fertilize PLANTS, not "the soil". Worms do that for me. If the plants are showing signs of deficiencies I address said deficiencies. For me last year, growing in containers, that meant weekly applications alternating magnesium in the form of epsom salts for everybody and leftover whey from my yogurt making to mostly tomatoes and occasionally peppers. Last year everything was in containers, growing in the mess of splinters and chunks of ground up lumber that passes for "garden soil" these days, I had to fertilize once a week with an NPK fertilizer, mostly for the N because wood chips tie up nitrogen when you have to plant IN it instead of just UNDER it (as mulch).
If you have caliche in your area I doubt you need to amend Calcium. I agree with others, get a soil test done by your local extension agency. There is hard caliche and soft caliche and they require different methods to deal with them, if you've got that.
Cover crops do wonders for breaking up and amending clay soils. Buckwheat worked well for that for me, but I'm not sure what kind of cover crops would be most helpful in your area of Utah. I liked buckwheat because once you plant it, you just mow it down (like with a regular mower) after it sets seed and it self seeds the next crop. Where I was living in OH, I could get 3 crops before winter set in. It doesn't have roots that go as deep as some clovers, but it generates a lot of root mass in the near layers of soil a lot faster, and a lot of vegetation up top, a lot faster than clover. It breaks up the clay a lot faster, or at least it has for me whenever I've used it. And its not hard to eradicate from your garden when its done its job.
Mulch heavily, use cover crops where you can, and worms will improve your soil for you. Last year I had almost no worms. Now I find them everywhere I stick a shovel into the soil or when I push the mulch back, they are there because I made a home for them and they are diligently doing the work of soil improvement for me.
