In a vain attempt at producing gold, 17th-century alchemist Hennig Brand accidentally discovered elemental Phosphorus while heating in a glass retort the residues from boiled-down urine. In modern times, this ‘liquid gold’ is seen as a potent source of increasingly limited phosphorus and useful nitrogen fertilizer. Its application in the garden is profound, but it should not be used without careful consideration.

Join us for a continuation of our Waste Not series, where biochar facility manager Dan Hettinger takes an in-depth exploration into the chemistry and applications of everyday household waste materials. We’ll explore the chemical composition of urine and establish methods for safe application. Following, Dan will share his experience using urine as a primary nutrient in hydroponic growing and experimental duckweed farming, along with other obscure historical uses, including its use in natural dyeing processes and the manufacture of saltpeter. This is part 3 of the edited version from the live stream with corrected audio and higher video quality.