15 Homemade Organic Gardening Sprays and Concoctions That Actually Work : Planet Green. Bradford Research and Extension Center: Building a Passive Solar Greenhouse. Recycling animal and human dung is the key to sustainable farming. © Illustrations in red & black: Diego Marmolejo for low-tech magazine.
The innocent looking water closet breaks up a natural cycle in our food supply. Basically, it turns extremely valuable resources into waste products. When we grow crops, we withdraw essential nutrients from the soil: potassium, nitrogen and phosphate, to name but the most important. Pearltrees.