This episode is the return of David Bos, a guru of organic, biodynamic farming, and one of Inside Winemaking's most popular guests.  For those that have yet to listen to David's initial interview ( #011 "Beyond the Cowhorn" from Februrary, 2015) I would suggest listening to that first.  During his round two we get explore compost, its creation, and how to source high quality material.  David gives a background on his early experiments with biochar, something that has a potential to aid compost in the soil and also describes rock dust, AKA Azomite.   In the second part of our discussion we talk about the critical elements of running on organic spray program for grapes, specifically to control powdery mildew.  There is a lot of hippie information about "natural wines" out there and David gets frank regarding what he considers natural and how organic farming fits into the battle with powdery mildew.  Our conversation weaves in and out of technical farming and then even touches into some of the biodynamic preparations and how, and when, they are used in the vineyard.  Always one to put his words into action, you can check out David's own wines at BosWine.com and the new Wine and Swine Club.   LINKS AND RESOURCES MENTIONED IN THIS EPISODE Bos Wine Main Website Earthbound Compost More on Biochar More on Azomite Some of the organic mildewcides discussed in this podcast: Stylet Oil Serenade Sonata  Biolink Sticker/Spreader Univ. Cal. Integrated Pest Management for Powdery Mildew