The act of composting is as old as farming itself. There are many documented cases of composting in history, yet there’s still a sense of mystery surrounding it.
From green bins in kitchens where we toss away our vegetable peelings, into rich, fertile soil, where does the transformation happen? When do food scraps become compost?
Today, we’re demystifying composting. We’ll go over what composting is, breaking down the “composting equation” to determine what’s required, and what’s produced. Finally, we’ll look at how compost tea goes beyond regular compost, working wonders to maximize the potency and growth of your crops.
What is Composting?
Bacteria and microorganisms in the soil have evolved to form symbiotic relationships with plants. Symbiotic relationships are mutually beneficial. In the circle of soil-life, old plant material provides food for microorganisms. Through their metabolism, microorganisms release nutrients into the soil, which younger plants use to grow.
Composting is the process by which organic matter, such as your food scraps, is decomposed by microorganisms to produce a crumbly dark soil. This soil product is what we call compost, and it is responsible for providing key macro and micronutrients to developing crops.
The Composting Equation
Through the composting process, your initial organic waste can shrink by as much as 60 percent in volume and 50 percent in weight. The science behind this is quite fascinating. In order to break down the organic matter, the microorganisms need oxygen and water and, in return, produce carbon dioxide, heat, water, and compost.
In the form of a (simplified) equation, it looks like this:
Organic matter + Oxygen + Water → Carbon Dioxide + Heat + Water + Compost
Let’s dive into each player in this biological equation, starting with organic matter, which is composed mostly of carbon and nitrogen.
The Role of Carbon in Organic Matter
If you’ve ever stopped to inspect a compost pile, you know that there’s more to composting than veggie peels and dirt. Between the layers of kitchen scraps, you’ll often see other materials dispersed throughout, like straw.
Straw is a popular addition to composting piles because it contains sugar, one of the main sources of carbon for microorganisms. Wood shavings, sawdust, and cardboard are other common sources of carbon used in composting. The carbon content in organic matter provides the energy for our beneficial microorganisms.
The Role of Nitrogen in Organic Matter
Microorganisms also need nitrogen in order to make proteins. Nitrogen usually comes from different types of manure. It’s important to note that not very much nitrogen is needed in composting, especially when compared to carbon.
The typical ratio of carbon to nitrogen is 30:1. Though the need is smaller, not enough nitrogen means that the composting process is much slower. Slow composting can lead to nutrient imbalances and loss of heat, reducing the quality of your compost product.
On the other hand, too much nitrogen can produce a foul odour, one of the most common problems associated with composting. Odour can be controlled, but this requires work and understanding of the components within the system.
The Role of Oxygen and Water
The microorganisms in composting are all aerobic bacteria, meaning they need oxygen to survive. Aeration, or the process of replacing oxygen-deficient air with fresh oxygen-filled air, is key for successful composting. This is why when starting a compost pile, a good mixing of the organic materials is required.
Porosity is the amount of space between the different particles in your compost mixture. These gaps of air are critical in delivering fresh oxygen to the bacteria, who are working hard to break down the organic material. Turning over and avoiding compacting are simple ways to maintain porosity within the compost.
Water can affect the composting process as well, if that water fills the porous gaps we just talked about. Too much moisture content prevents oxygen from reaching the bacteria. However, those same beneficial bacteria also need water in order to function. A moisture content of between 40-60% is considered optimal.
The Role of Carbon Dioxide
Carbon dioxide (CO2) is produced as a by-product of microbial metabolism. This is a natural part of the carbon cycle, and is not to be confused with the carbon-based emissions that are responsible for climate change.
In composting, CO2 is stored within the soil, acting like a sink for atmospheric carbon. Plants also aid in this process, taking up CO2 through their stomata (tiny pores on their leaves and stems) during photosynthesis. Both composting and growing act to remove carbon emissions from the atmosphere, turning them into nutrients within the soil.
The Role of Heat
If you’ve ever argued about what temperature to set a thermostat, you’ll be happy to know that the microorganisms also have their own preferred temperatures.
Bacteria can be grouped based on these preferences, into mesophilic and thermophilic classes. Don’t stress about these names. All you need to know is that mesophilic bacteria prefer lower temperatures, while thermophilic bacteria thrive in higher temperatures.
The Heat Phases of Composting
In composting there are three heat phases: the mesophilic phase, the thermophilic phase, and a cooling and maturation phase.
In the mesophilic phase, as you would expect, mesophilic bacteria are dominant and begin initial decomposition. This process releases a lot of heat, setting the stage for the next phase, where thermophilic bacteria take over.
As thermophilic bacteria grow within the compost, the internal heat rises. In this hot environment, most pathogens that cause plant disease are eliminated. This continues until the food source for the thermophilic bacteria runs out. As these bacteria start to die-off, we enter the cooling and maturation phase. Here, mesophilic bacteria and soil organisms like earthworms return to finish the composting process.
In this intricate and dynamic process, the diversity of different soil microorganisms is key to successful decomposition.
Compost and Compost Tea
Now that we’ve broken down the compost equation, let’s talk about something you may or may not have heard of – compost tea.
Compost on its own is great for plants. It contains the nutrient profile that plants want to grow in. It also creates a healthy soil environment for bacteria and larger organisms to thrive in. However, compost tea has even larger benefits.
Compost tea is a liquid brewed from compost that also can protect the roots of cannabis plants from pathogens. Other benefits include increasing beneficial bacteria populations and diversity, improving soil structure to allow better rooting, and keeping stomata open for more carbon dioxide intake and plant growth.
Compost tea will also attract earthworms that aerate your soil; improving drainage and bringing up minerals to the roots of your cannabis. Earthworms also produce castings which are full of nutrients that your plants can easily absorb.
What BlueSky Organics Can Offer
Brewing your own compost tea is a long process. It starts with creating a balanced mixture of starting organic matter, and requires maintaining optimal conditions while waiting for maturation. Finally, the last step requires extracting from the compost, producing the liquid gold that is compost tea.
Luckily, a dry compost tea solution is available through BlueSky Organics. Vit-Alive allows for robust and quick growth, leading to a potent cannabis crop. This compost tea will protect your plants from disease, accelerate their growth, create a healthy ecosystem for beneficial microbes, all while maximizing yields and increasing terpene production.
Vit-Alive is most effective when used in conjunction with BlueSky’s Organic Booster. Easy-to-use and hugely beneficial, this winning combination is a proven solution for producing high quality crops.
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