This Earth Day, we want to talk about one of our favorite topics here at the Kearsarge Food Hub - SOIL!
We spend a lot of time, energy, care, and love nurturing our soil on Sweet Beet Farm - a foundational program of ours here at KFH - because it is the most essential building block for growing nutritious, delicious foods that feed our community. When it comes to soil, we always want to give back more than we take.
This is time and effort well spent and much needed, now more than ever.
Why?
Because across the globe, and particularly in developed countries like the US, we’re suffering from a major crisis of soil loss. In fact, we’ve lost over a third of the world’s topsoil in the past 150 years due, in large part, to the irresponsible and harmful practices of industrial agricultural - like monocultures, using heavy machinery, and leaving the soil bare - that cause soil erosion and nutrient depletion at alarming rates.
Soil loss not only compromises our ability to grow food, but it also compromises natural systems that would otherwise be in balance, like the carbon and water systems. Soil that’s bare and eroded releases carbon into the atmosphere (while rich, healthy soils and flora ecosystems have the ability to store huge amounts of carbon). Soil erosion and compaction leads to increased runoff, reduced infiltration, water pollution, and more, affecting the availability, quality, and distribution of water resources.
There is also an enormous economic cost to soil loss. According to the Natural Resources Conservation Service, in the United States soil erosion has caused an estimated $44 billion in economic losses since the 1980s due to crop loss and other economic byproducts of soil loss.
Of course, where there’s challenge there is also opportunity. Improving soil health can increase crop yields by 20-50% while reducing the need for fertilizer and pesticide use.
So how can we improve soil health?
This is a main question we’ve been exploring on Sweet Beet Farm for the past 8 years, and we’ve come up with a short list of 5 essential (and not at all unique to us!) soil-building practices for any sustainable farm.
Let’s dig in!
1.Keep the soil covered.
Tarps in action covering beds on on the farm.
Keeping the soil covered is a primary tenet on Sweet Beet Farm, and indeed for any farm that practices sustainability. Covering the soil prevents soil erosion from wind and water, helps retain moisture, and prevents weeds. All of this makes life on the farm much, much easier.
We have a running joke on Sweet Beet Farm that tarp is the employee of the month, every month (of course, the people working on the farm are the actual heroes of the month, every month!). Without complaint, tarp covers the soil for us when and where we need it. We use a black plastic tarp (there’s actually a lot of plastic used on modern farms, an area where there’s room for growth and finding alternatives when possible), which gets heating by the sun, kills weeds, and keeps the soil warm and moist.
Other than tarp, cover crops keep the soil covered, with the added benefit of contributing nutrients back to the soil. Some common cover crops, like peas, “fix” nitrogen which they mean converting atmospheric nitrogen into usable “food” for plants (aka they make fertilizer!)
2. Minimize soil disturbance.
The broad fork in actual for its second most important use - playing music.
On the farm we try to disturb the soil as little as possible because we want it to thrive with its own complex ecosystem of worms, microbes, and other living things!
To do this, we practice minimal tilling and minimal soil compaction. We don’t use big tractors or till deep into the soil. When we need to, we use a hand-held tractor called a BSC, to till up the soil just enough for planting, or other use a broad fork to losen soil in the beds for planting (which happens to double as an instrument).
Permanent raised beds on Sweet Beet Farm.
We also utilize a permanent raised bed system. This means we have permanent planting space, which is mounded soil 30 inches wide and 100 feet long (which are the dimensions that allow us to easily work in the beds and make the best use of our tools), and designated walking rows to prevent compaction of the soil where we grow.
3. Adding / maintaining lots of organic matter.
Adding organic amendments for soil fertility.
The plants we grow need lots of food to be as healthy and packed with flavor and nutrients as possible. Adding organic compost to the soil boosts fertility and maintains a good texture. Compost can come from animal manure, garden clippings, leaving plants to decompose in the fields, wood ash, and more.
We’re on a journey to generate our own compost here on Sweet Beet Farm. This way we can bring in fewer inputs from external sources, like organic fertilizers and manure, and build a closed loop system where we take farm waste to create our own soil fertility.
4. Crop Rotation.
Tomatoes planed alongside lettuce.
One extremely harmful practice of the industrial food system that’s responsible for high levels of soil loss and nutrient depletion is monoculture.
Monoculture means planting just one crop in the same space, over and over again. Driving through the midwest United States, for instance, you’ll see corn planted as far as the eye can see. This is incredibly damaging to the soil in the long term.
On regenerative farms like Sweet Beet, we grow a diverse set of crops and practice crop rotation, making sure that crops are planted in different spaces throughout the farm from season to season, planting to planting. This means we aren't pulling the same nutrients out of the soil by keeping the same things planted in the same space.
Different crops not only pull nutrients from different soil layers but they also provide different benefits to the soil. Radish roots can help to aerate, for example, which makes it more able to hold moisture and easier to plant in (among other benefits).
5. Mimicking nature as much as possible.
Essentially, all of these practices in particular and the foundational ethos in general for a sustainable, regenerative farm is to mimic nature whenever and however possible. Natural systems inherently possess the wisdom of how to maintain balance or restore balance when it has been thrown off. We learn from nature that soil is a central key to maintaining balanced, healthy ecosystems on the land.
Soil works best when undisturbed and teeming with life. Interestingly, when you employ sustainable soil building practices on the farm, largely by promoting and protecting its natural vitality, you automatically reduce risks like pest and weed pressure. The system becomes more balanced and resilient, meaning there’s less chance for one thing to wipe out an entire crop.
And when it comes to the food we eat, it’s only as nutrient dense as our soil is. Not every carrot is created equally! Healthy, thriving soils yield highly nutritious - and flavorful - foods for generations to come.
Sweet Beet Farm in mid-summer, surrounded by forest.
What’s the takeaway? Soil is powerful and it needs our attention and protection!
At this point, on Sweet Beet Farm we’re beyond the pursuit of sustainability and into the realm of regenerative soil building practices. That’s because we’re not just trying to sustain - we’re trying to regenerate, rebuild, and renew soil to the most vibrant possible state. We hope you’ll join us however you can, because the future of life (and delicious, farm fresh foods) truly depends on it.