I guess it is in general difficult to measure health. Often we take the absence of disease symptoms to declare health, even in our own human health which probably got us into treating symptoms all the time. But killing the mildew on the plant doesn’t make it more healthy – it just makes the mildew disappear (for a while).

If I want to “measure” soil health in my daily life I usually look at the produce, plant and soil:

• taste, smell and texture of the produce. I guess with the size of your operation you could even create your own panel to make regular documented taste tests
• use of pesticides, fertilizer. If your soil is strong and healthy you shouldn’t need a lot of those products.
• visible inspection of the plant, if the plant is healthy, soil should be healthy or at least decent as well. I’m in the process of making a sheet to evaluate plants regularly so we can see a development over the season but also compare it to seasons prior.
• soil analysis. Dig a hole, look at the soil, color, crumbs, smell it taste it, document it to see development. Make regular infiltration tests, slake tests… to compliment
• visible soil life as an indicator, I remember someone relating rain worm amount and type to other soil life or what kind of soil life community we have. But even bigger animals like birds might show improvement or change in soil health.

As you can see I am a big advocate to use our own senses and trust ourselves. Animals are well known to select by there senses in everyday life, we should have the same capabilities. But we need to train them again and can take some help of pen and paper (or bits and bytes) and some simple on farm testing.

If you involve you staff in this process there might be more positive side effects on the way.