Sustainable Soil Fertility
The food we purchase is how we farm or grow, our food. When we purchase food that has been grown with p g less sustainable practices, these are the types of practice we are encouraging.
We often think of sustainability in terms of using nonrenewable resources carefully. More important, however, is learning to use renewable resources well. If all the Earth’s agriculture became organic tomorrow, it would be wonderful and challenging. A healthier resource-conserving, food-raising, and planetary ecosystem would be possible. However, there would be new challenges to how to manage the renewable resources within the system.
The cost of purchasing the cured compost needed to grow food organically would skyrocket because the demand would exceed the current supply. It is a reason for which we need to learn how to properly preserve, manage, and develop our renewable resources. Soil, for example, needs a given level of humus, or cured compost, in order to thrive. Therefore, we each need to make sure we grow enough organic matter to properly preserve the renewable resource of soil.
The Loss of Soil Nutrients and Humus
When soil grows crops, the crops extract nutrients as well as hummus from the soil. To maintain the soil’s fertility, the nutrients and humus must be replenished. Both of these needs can be met simultaneously when the crop and all other residues from those who consumed the edible portion of the crop are composted returned to the soil.
The cured compost will have almost all of the nutrients that the crop contained and, p, depending on the crops that are grown, enough humus to replenish the soil’s supply.1 The carbon that left the soil in the form of carbon dioxide will be returned if plants that store large amounts of carbon in their mature bodies (such as corn, amaranth, wheat, and rice) are grown and added to the soil as cured compost.
Initially Adding Nutrients and Humus to the Soil
Not all soils naturally have all of the nutrients that they need for their optimum health and crop productivity. Deep-rooted crops such as alfalfa and comfrey can be grown to bring up nutrients from below the range of most roots, then composted and added to the topsoil.
Additionally, when cured compost is added to the soil, nutrients that were previously unavailable in the soil may be made available by the geologic cycle. (In this cycle, humic acid which is produced from the decomposition process and is contained in the cured compost along with the carbonic acid developed around the plant’s roots, can increase soil microbial activity, decompose larger minerals, and possibly alter soil pH so that previously unavailable nutrients are made available.) However, if the needed nutrients are not in the deeper regions of the soil, they will not be present in the cured compost. In other words, if the nutrients are not present, the cured compost made from plants grown on the nutrients-deficient soil will not contain the deficient nutrients, and the soil will still be unbalanced even after the cured compost is added.
100% Sustainability Impossible
Some nutrients will escape from the garden or mini-farm, whether from leaching, from rainfall-runoff: or from wind picking them up and carrying them away(although water and wind erosion are usually not a problem when the soil’s humus supply is maintained and all of the GROW BIOINTENSIVE techniques are used).
At the same time, however, nutrients are added naturally to the mini-farm through rainfall, wind, they g, breakdown of the soil’s parental rock material, and the up soaking of groundwater. With GROW BIOINTENSIVEsustainable gardening and mini-farming, the gain nutrients may eventually near the loss of nutrients and the soil’s nutrient balance may be maintained if all nutrients are recycled.