On thousands of acres of orange groves in Florida, farmers are adding beneficial fungi and bacteria to the soil, which makes the oranges grow bigger and sweeter–and makes the soil suck up enough extra CO2 so that each acre offsets the emissions from a passenger car. Call it probiotics for soil.
“Agricultural soils are one of the world’s largest carbon sinks,” says Paul Zorner, CEO of Locus Agricultural Solutions, the startup that makes the particular combination of probiotics in use on the farms. “If they’re treated right, you’re going to absorb a lot of carbon dioxide out of the atmosphere.”
When plants take up CO2 during photosynthesis, creating sugar that they use for growth, they also release sugars through their roots, attracting microbes. Healthy soil is full of these microbes, which then keep the carbon in the ground. But conventional farming–including the overapplication of chemical fertilizer–has destroyed the microbial balance. Adding “probiotics” helps restore it.
The facilities are smaller than a beer brewery; the fermentation devices are small, and in a space roughly the size of a conference room, the company can produce enough of its product for 30,000 acres of farms a month. The microbes are applied while the field is irrigated or just spread on the surface. The first production system is in Cleveland, though the company plans to begin building them locally near farms across the country. “One of the key features of this local microbrewery is we can actually optimize for local conditions–soil type, crop, temperature, a whole variety of things–where we can work with individual growers to better understand how to solve their specific problems, as opposed to just having one product that would be used the same, regardless of where in the country you’re trying to operate,” he says. Eventually, it could also be produced in parts of the developing world. “It’s a system that could be shipped in a boxcar and set up relatively easily, as long as you have a basic power source.”
“I think people are really waking up to the fact that agricultural soils really are a remarkable part of the solution [to climate change],” says Zorner. “We need to empower growers to do this.”