Updated: Jun 20
More and more market gardeners are taking action to improve the quality of the soil they produce. It’s not a surprise that earth-friendly farming techniques, like lean or no-till farming, are gaining popularity.
Many market gardeners improve soil fertility with soil health management systems like cover crops and diverse rotation. This allows them to increase their land’s production potential in the long term.
But what does it look like to farm with soil health as a main priority?
Gabby Tuite and Henry Webb from Old Road Farm in Vermont are great examples. They’re two of many market gardeners for whom soil health is always on their minds when making management decisions on the farm.
In the past few years we have been farming at our current location, we have seen soil health and productivity increase with careful application of amendments and fertilizer, cover cropping, mulching, and other soil health-focused practices. - Henry Webb
I’ve had the pleasure to discuss with Henry, who was one of the guest speakers for the conference “Soil Health: Farms, Fields and Gardens” at the NOFA-VT event last February.
He helped me define soil health and gave his advice on which factors improve soil fertility throughout all your farming years!
What is soil health?
The concept of soil health refers to the sustained ability of soil to operate as a critical living ecosystem that supports the growth of plants, animals and humans.
Indicators of soil health
Healthy soil depends on many things. You can identify healthy soil with physical and chemical indicators.
Bulk density, soil aggregate stability and water holding capacity are considered ideal physical indicators of soil fertility, among others.
Similarly, pH, EC, soil organic carbon and soil nutrient status are some of the well-established chemical indicators of soil fertility.
5 reasons why is soil health important
Healthy soil provides numerous advantages beyond the production of crops, such as clean air and water, flourishing crops and forests, productive grazing fields, diverse wildlife, etc.
Soil accomplishes all of this by carrying out 5 fundamental functions:
Regulating water: Soil plays a significant role in managing the movement of rain, snowmelt, and irrigation water. Water can either run off the surface of the land or infiltrate and move through the soil.
Sustaining plant and animal life: The diversity and productivity of living things depend on soil.
Filtering and buffering potential pollutants: The minerals and microorganisms present in soil perform crucial functions such as purifying, neutralizing, breaking down, retaining and eliminating organic and inorganic materials. This includes by-products from industrial and municipal activities, as well as deposits from the atmosphere.
Cycling nutrients: The soil is responsible for storing, transforming and cycling various nutrients, including carbon, nitrogen, phosphorus and several others.
Providing physical stability and support: Soil structure provides a medium for plant roots. Soil also provides support for human structures and protection for archeological treasures.
Contrary to common belief, creating and maintaining healthy soil implies more than just reducing erosion. To succeed, you need to follow the 4 principles of soil health, which consist of:
Maximizing soil cover year-round to control wind and water erosion, keep more moisture in the soil for plants, maintain a moderate range of temperatures, reduce soil compaction and suppress weed growth.
Minimizing soil biological, chemical and physical stresses such as overgrazing or undergrazing, excessive application of pesticide or tillage and compaction. Minimizing soil disturbance is one of the crucial steps to enhance long-term soil productivity.
Maximizing Biodiversity with plant diversity and crop rotations to improve rainfall infiltration or nutrient intake while reducing risks of pests and diseases. This approach can help to increase the diversity of soil microorganisms, beneficial insects and other species, ultimately leading to a more robust ecosystem.
Maximizing the presence of living roots; living plant roots exude compounds that nourish much of soil life, which is why it is important to increase the acreage, leaf area and length of green growth.
For Henry, healthy soil depends on a lot of different things depending on individual farms’ goals and circumstances. The important thing for new farmers and market gardeners is to try to be not too dogmatic in their various methods of achieving a common goal.
Speaking of various methods! With Henry, I’ve established which factors improve soil fertility and a few methods that can help you maintain healthy soil year-round. Here they are!
Use Cover Crops
In agriculture, cover crops are plants that are planted to cover your soil, not for harvest. They can include clover, buckwheat, rye, etc.
They’re primarily used to :
Slow erosion ;
Improve soil health ;
Enhance water availability ;
Smother weeds ;
Help control pests and diseases ;
Increase biodiversity ;
Provide resources that support pollinators ;
Cover crops are a green, protective layer for your soil through the winter months or fallow times. Not only do they conserve humidity for the crops, but they also protect the soil surface from the forces of nature, like intense rain or dreadful summer heat
Furthermore, cover crops provide habitat when the soil would otherwise be barren. This habitat supports a diverse range of wildlife both on the ground and beneath it, by providing food and shelter to them.
Build Organic Matter in the Soil
Healthy soil depends on the quantity and quality of the organic matter in the soil. Organic matter, like carbon, is one of the major signs of the land’s productivity. Building organic matter in the soil is therefore important for healthy plant growth and overall soil health.
Here are some ways to increase organic matter in the soil.
Compost is an amazing source of organic matter useful when added to increase soil fertility. You can either buy your compost or make your own. When making your own, use food scraps, yard waste and other organic materials.
Market gardeners use mulch to keep the soil cool and moist, block out weeds, prevent frost heaving in winter and simply make the whole landscape more aesthetically pleasing.
You can mulch with organic materials like leaves, straw or grass clippings. Mulching will help you increase organic matter in the soil by breaking down slowly over time.
Use green manure
Green manure is another term to refer to cover crops, although technically a cover crop doesn’t become green manure until it’s dug into the ground.
Add animal manure
Animal manure is another great source of organic matter for your soil. You must use it in moderation, however, as too much can lead to nutrient imbalances in the soil.
Reduce tillage with No-Till Practices
Another thing healthy soil depends on is a balanced composition and adequate pore spaces.
A typical soil is approximately composed of :
45% minerals (sand, silt, and clay);
5% soil organic matter;
The water and air occupy the pore spaces between soil aggregates. However, the use of tillage implements can gradually diminish and eliminate these pore spaces. This leads to restricted infiltration and the disruption of the natural balance of organic matter in the soil, making it less fertile.
No-till practices minimize disturbance while maintaining healthy crop growth. Reducing tillage with those practices allows your soil to thrive by soaking up, storing and filtering water efficiently.
Some No-till practices that can be implemented are crop rotation, intercropping, conservation tillage, composting and more!
Although, for Henry, no-till practices aren’t always easy to implement at scale in some organic vegetable productions. That’s why he believes the focus should be more on reducing tillage than eliminating it.
I think there should be a focus among organic producers on using tillage intelligently and as part of an overall management plan that helps build organic matter and soil health rather than trying to avoid all tillage. - Henry Webb
Test the Soil at Least Once Every 4 Years
Maintaining fertility and pH is essential for your farm’s productivity. Healthy soil depends on frequent soil testing. This allows you to have an indication of trends in soil fertility, pH and organic matter levels in each field. That kind of test also helps determine the amount of fertilizer needed on the field.
Let’s say you’ve had manure previously applied in your field, as well as a history of high soil fertility. In that case, you can potentially save costs by opting to plant cover crops that would help retain those nutrients in the soil, rather than adding unnecessary nutrients.
Also, according to Henry, every market gardener and farmer needs to know how to read a soil test as well as how to assess their soil by look, feel, smell, etc. Note that the appearance of healthy soil depends on your management goals.
As for testing your soil, Henry considers once every 4 years to be a minimum.
I prefer to soil test more frequently than every four years. We soil test once a year especially with high production crops. We do this in the fall to help guide next year's crop plan and fertilizer application. - Henry Webb
Healthy soil depends on so many things, but it would be more accurate to say that so many things depend on healthy soil.
To put it simply, without soil, there is no life. Healthy fertile soil is one of the main things, if not the most important, you need to successfully grow crops. Understanding your soil is a continuous adventure from which you gain so much in the long run.
Learning to work with soil and seeing how it reacts to different management is endlessly interesting. - Henry Webb
Taking those small steps to improve your soil health will decrease the effects of flooding and make your crops more resilient to weather extremes. It will also improve the environment for wildlife.
But before anything, you need to know all the necessary information about your soil. After all, how can you make it healthier if you know none of its characteristics? Here are 5 things to know about your soil for better yields.
And on that note, I leave you with those last wise words from Mr. Henry Webb:
Building soil health takes a long time, so as much as possible I try to take my time and think in the long term. That's often difficult when trying to grow production quickly but it's important to keep in mind. - Henry Webb