生物动力农业入门讲座第 3 卷》，亚历克斯-波多林斯基著

Volume 3 continues Podolinsky’s presentation of biodynamic agriculture through nutrition and disease, soil structure, organic matter and humus, the biodynamic preparations, the living and breathing Earth, and the sustainability of humus.

Podolinsky wrote that 500’s effect develops with actively growing white feeder roots, rather than acting mechanically on bare soil. In sparse sandy grassland he observed the effect around the plants while the sand between them changed little. This describes where the response develops; it does not change JPI’s instruction to spray BD 500 on moist soil shortly before sowing or transplanting, mainly in spring or fall, after the prescribed one-hour stir. (Alex Podolinsky, Bio-Dynamic Agriculture Introductory Lectures, Vol. 3, p. 49.)

Podolinsky explains that cultivation can disrupt the structure and colloidal condition of active humus. He recommends Prepared 500 on newly cultivated vegetable soil so white hair roots develop as the crop grows and takes up elements, helping structure the soil within their reach. Follow JPI’s current Prepared 500 directions for the amount, stirring, water, and application. (Alex Podolinsky, Bio-Dynamic Agriculture Introductory Lectures, Vol. 3, p. 54.)

Podolinsky describes a citrus grove that had been organically managed for ten years, with regularly mowed white-clover-rich pasture beneath the trees, yet poor soil structure and white hair-root development, especially where “Round-Up” had been used. The oranges initially tasted “acidy bitter.” He says the herbicide after-effect made biodynamic soil-structure development take years longer than usual; as the soil gradually developed, “acidity reduced noticeably and was replaced by choicest sweet flavours.” This is his particular grove’s soil-and-fruit sequence. (Alex Podolinsky, Bio-Dynamic Agriculture Introductory Lectures, Vol. 3, p. 55.)