Closed-Loop Farming in Costa Rica
I woke up to the sound and smell of a chicken coop. It was a mild March morning in La Argentina, a small town on Costa Rica’s southeastern edge. I was staying on a small-scale, family farm of the gracious Señora Ana. Her farm, as with many of her neighbor’s, incorporates animal, vegetable, and fish production into a closed-loop system.
Closed-loop farming is, in essence, the most primitive form of farming. This system does not produce any waste at all—every single material in the system is recycled continuously. For this reason, this system is also called “zero-waste farming.”
There are 3 major components to keep in mind when understanding a zero-waste farm: soil, plant waste, and animal waste.
It is known that good soil quality begets healthy and plentiful crop production and vice versa. As a result, maintaining soil quality by ensuring that it is nutrient-rich is critical for farming. While most conventional farms add synthetic fertilizer to degraded soil, a closed-loop farm adds something else: compost and manure from other components of the farm. These substances contain concentrated amounts of NPK (nitrogen, phosphorous, and potassium), which are the main nutrients required for plant growth. Unlike synthetic fertilizers, these materials contain a myriad of naturally occurring minerals that also aid plant growth and health in supplement to the NPK.
Once the plants grow, just a percent of the harvest will end up being consumed by humans for food. What is left over, then, can go a few different places. On the farm in Costa Rica, one plant that they produced in excess was sugar cane. The excess sugar cane was fed to the pigs, which surprisingly loved it. They also ate excess pineapple. By feeding the animal left over plants, the process of breaking down the components of the plant is increased rapidly. While the leftover plants can also be deposited into a compost heap, where they will break down slowly into a material that can be used for fertilizer, they are preferably fed to the animals in order to both provide food to the animal and be broken down into manure, which can be directly applied to the soil.
As I mentioned, plant biomass can be converted to a usable material by compost or by an animal’s digestive system. As a result, manure from cows, pigs, and even fish can be applied as fertilizer to the soil. While conventional farms often have waste ponds on their premises, a closed-loop farm uses manure as fertilizer. In addition, manure may also be the primary input of a biodigester, which is a system that converts methane gas from decomposed organic matter into electrical energy. At Señora Ana’s farm, they were building a biodigester to provide the energy for their lights.
While the basic idea of a zero-waste farm involves the process I just described, there other ways that farms incorporate materials within their system.
For example, Señora Ana’s farm had chickens, which graze the land used for growing crops. This provides them with naturally occurring food rather than purchased chicken feed and contributes to the diversity of grasses in the pasture. This diversity of grasses, in turn, increases soil health, which we know is critical to farm productivity.
Furthermore, while the conventional view of farming assumes that monoculture, large farms are the most productive, which may be true monetarily, there are robust benefits of closed system farming. Primarily, this method of farming is best for the environment because it mimics a natural ecosystem. In addition, feeding animals primitive foods make them much healthier to consume, contributing to both quality and taste. Additionally, using already existing products from the farm as fertilizer dismisses the need to purchase synthetic fertilizer. This also protects the local environment from high-nutrient runoff that is quite damaging.
Most of all, zero-waste farming is a practice that brings the farmer closer to the land, and is one of the most fulfilling ways to farm– it requires both tradition and creativity. The look on Señora Ana’s face was enough to exhibit her commitment to and love of the land, the animals, and the food she produces for her community.