Compost and its Place in the Garden
Composting is one of the most important aspects of biodynamic gardening. The compost that goes into our garden provides it with all the nutrients it needs along with very important micro organisms that support a healthy soil. At Desert Marigold School, everyone is involved in making compost, from the children, to the staff, to the apprentices and volunteers. Everyone learns the layering techniques of creating compost piles. The two most important ingredients in layering compost are green material and brown material. The green layer provides the nitrogen. The brown layer provides the carbon. Each of these layers are thoroughly watered. The end result is achieved in a very short time (three to four months) and is well received into the waiting garden beds. Because we are in a dry desert, all the organic amendments the soil needs for fertility are consumed very quickly. An ongoing compost program is essential to sustain our numerous agricultural projects.
All our “windrow” compost piles are constructed four feet wide by three feet high by 20 feet long. This allows for a sufficient flow of oxygen into the core of the pile producing optimal conditions for aerobic microbial break down. These dimensions cannot increase without the internal temperatures exceeding the proper range of 120 to 140 degrees. Above these temperatures the pile will go anaerobic (without oxygen) and kill most of the beneficial microorganisms. The thermophilic microbes include a multitude of bacteria, actinomycetes and fungi all of which add to the timely decay of the biomass in the compost piles. The climate we have in the desert being dry and hot actually contributes to a much faster decomposition of the layered organic material used in this style of composting. The windrow piles are constructed in multi-layers, green (nitrogen), water, brown (carbon),and water then back to green, then water, then brown, then water, etc until a height of 3 feet is reached. The Green layer is any fresh green clippings from the campus including weeds. In summer, amaranth is the main weed we use, later on in spring it is mallow. The brown layer is wood chips or any unbroken down material from older compost piles. Water is essential in activating compost layering. Without water the material will desiccate in our climate and produce light, brown, unbroken down dry organic material, not the rich black moist humus we are looking for. The end result of composting “Humus” is the essential building block to healthy fertile soil. It creates “tilth” (The state of aggregation of soil and its condition for supporting plant growth) and provides the soil its fertility.
The building blocks for our compost piles are gathered from the microcosm that is the 12 acres of DMS. All the organic material on our property is utilized in this process. We prune a tree, or limbs fall during a wind storm and these wood products are chipped and become the brown layer. Weeds grow in the garden and in the irrigation ditches and they are gathered and become the green layer. Nothing is wasted or lost. All is turned back onto itself, to feed and renew, again and again.
Last but not least are the biodynamic preparations added during the composting process. The six preparations used in our compost piles are both plant and animal based and are the foundation of Rudolf Steiner’s creation of the biodynamic style of gardening. The “BD preps” inoculate the windrow piles with pro-biotic elements to add in microbial decomposition, while also supporting in healing the earth around the area where their applied.
Once the compost is added and incorporated into the vegetable beds of the garden the benefits become apparent. The whole ecosystem in a Biodynamic Garden is a model of sustainability. At its core is the fundamental movement toward balance and harmony. All living things have a place in this garden model. The birds, the bees, the insects, the toads, the gophers, and yes especially the weeds. All these living things have an important part to play in a biodynamic garden. Compost is its most important link. It makes it possible for this extraordinary symbiosis of nature to create a harmonious abundance which is capable of feeding our community now, and into the future.