SO… we added clay to our beds last autumn, and we grew oats in those beds over winter, and now in mid August we had to remove the oats to put in an early seed crop. We tested the brix of those oats. Their brix was 22 and those around them 19. When we pulled them up there was a very obvious difference to the look of the roots which are very clearly looking for clay to get into!!!!!… a continuing journey to remineralise and create /regenerate our soil to grow high quality food and seeds!
We have light pumice soils so the idea of the clay is to increase the cation exchange capacity to speed up the process of building soil. You can see there are more exudates (sugars) coming out of the plants which why the clay and soil is sticking to the roots.