In this episode, Jo and Kate are joined by Mark Tupman from Productive Ecology.  For over two decades Mark has been active in the fields of organic/biodynamic production, permaculture, sustainability, agro-ecology and holistic management and in between times managed an orchard, animals and food gardens on his own property.  In this conversation, Mark shares some of his extensive knowledge on the interplay between the soil environment, soil biology and nutrient availability.