By Mary 'Klibs' Dralle, for Let’s Talk Plants! November 2023.
Editor’s note: Please welcome Mary 'Klibs' Dralle, the new permaculture contributor to Let’s Talk Plants!
Permaculture and Urban Carbon Farming
Our Mother, The Earth, is very modest and always building up good topsoil covered in plants of every kind. When you look over a native landscape, like the desert, do you see how nature maintains itself or do you see a barren wasteland? Often times, many see only the latter. A lot of dirt and not very many plants. However, come back in 5,000-10,000 years, and the view will most likely change. Why you ask? Nature knows how to nurture herself back into health. It may take a great many years, but it can be done. `
Our current climate has been impacted, in part, by man's need to create a mechanical society that often times disregards nature. We have turned vast areas that were once filled with lush topsoil and abundant plant life into dirt. Why does this matter? In two words, carbon sequestration. Pulling CO2 out of the atmosphere and putting it back into the ground where it belongs.
It is necessary to keep the soil itself vibrant, with a high soil organic carbon (SOC), as it plays a major role in the carbon sequestration by absorbing it from dead plant matter. The first 36 inches or so can contain up to three times the amount of CO2 than is found in the atmosphere provided it is not tilled. Once the soil is turned over, the top layer that has been exposed to the sun, and has less microbes, is sent under the surface and living soil is brought up top. As the sun heats up this new top layer, it becomes too hot for the microbes to live thus resulting in diminished soil on top and bottom. When plants are added and take up nutrients, the soil starts to die and turn back into dirt.
Plants are the best solar power plants on the planet. Photosynthesis is powered by the sun. A plant's leaf will pull CO2 from the atmosphere, convert it into sugar and send it into the root system where it is stored for future use.
It is represented in this equation:
Carbon Dioxide + Water + Sunlight -> Glucose and Oxygen. 6CO2 + 6H2O + Sunlight -> C6 H12 O6 + 6O2
This is what carbon farming is all about and plants do all of the work.
Does this apply to large scale farming only? Actually, it applies to the entire process of plant growth everywhere and is called regenerative farming, as well. While organic practices are often used to promote good soil, permaculture takes the whole process into account and is all inclusive regarding the energy cycle, minimizing waste, and supporting nature's ability to provide abundance. One example is fertilizer. By using farm waste and reducing the dependence on outside sources, the topsoil is continually grown to improve plant life.
According to the USDA Forest Service, in one year, one mature tree can absorb more than 48 pounds of carbon dioxide. It is permanently stored in its fibers until the tree or wood experiences a physical event that releases it into the atmosphere, like fire or decomposition.
If it is an apple tree, it does double duty as it produces fruit as well. A good permaculture way to keep that tree healthy is to under plant it with edibles such as day lilies and garlic chives at the drip line of the tree to prevent grasses from taking hold. Using bee balm, dill, and fennel, in addition to being food themselves, will attract the pollinators. Also, 4 to 6 inches of mulch on any open soil keeps it from drying out and turning back into dirt. This is referred to as a Fruit Tree Guild.
If a typical suburban neighborhood had one or two tree set ups such as this in each yard, it would sequester between 50-100 lbs. of carbon and produce food at the same time thereby creating Urban Carbon Farmers. Plus, it would supply locally grown foods that take the burden off vast quantities of land that use current practices such as tilling the soil, pesticides, rodenticides, herbicides to control the growing environment, and reduce emission pollution from transporting food from farms to stores to tables.
On the other hand, if the yard grows annual crops year-round and all plant materials are kept on site for compost, that is another example of small scale. Other suggestions would be Dymondia, or other cover crop, instead of lawns; sheet mulch instead of rocks and seasonal native wildflowers instead of weed cloth.
While not every home has a yard, there are other possibilities. For example, the permaculture practice of growing a blueberry bush in a repurposed five gallon frosting bucket from the local bakery, would be a good start for a small scale carbon farmer. Make it into a wicking bed bucket and it can be placed next to the front door of an apartment. Every little effort counts in urban carbon farming!
