One of the most remarkable passages from Alex Podolinsky's remarkable work in Australia with biodynamics is this one, which bears endless repeating:
“In the early days we ran trials. Depleted soil was deep ripped. We sowed the right species and applied 500 and had the well known results. In six years we raised the organic matter levels from 0.9% in the top 4” to approximately 12% and, varyingly, to 2.4% at 40” depth. Ripping exactly the same way etc, but without 500, the soil biology developed to 20 cm depth, no further. In modern farming the right soil treatment and the Bio-Dynamic preparations must be applied together."
-Alex Podolinsky, Bio-Dynamic Agriculture Introductory Lectures, Vol. 2, pg. 15.
These remarkable results are in Australia, one of the most difficult growing regions on earth. If such results can be attained there, they can likely be obtained anywhere else.
Alex Podolinsky used 500P, which is regular 500 plus all the compost preparations. This mirrors what Ehrenfried Pfeiffer was working on in the USA with the Pfeiffer™ Field and Garden Spray which is an exclusive proprietary product from the Josephine Porter Institute.
If you're serious about improving your soil rapidly, these two options can work wonders.