Healthy soil is essential to a healthy garden. But what does soil health really mean, and how can we improve and maintain it?
The term soil health refers to the biological, chemical, and physical properties that enable soil to perform its basic functions. These include supplying plant roots with water, air, and nutrients; absorbing rainfall and reducing runoff; and breaking down and recycling organic matter such as plant residues and manures. Healthy soil performs all these functions with minimum inputs from the farmer or the gardener.
Boosting soil health yields many benefits, among them increasing plants’ access to soil nutrients, reducing the need to add fertilizer, suppressing plant disease, preventing soil loss, and increasing the soil’s ability to perform both in times of drought and in flooding rains. For the environment, enhancing soil health improves water quality and can curb release of planet-warming greenhouse gases by keeping carbon in the ground. 
The Virginia Soil Health Coalition, along with Virginia Cooperative Extension and other partners, has launched the 4 the Soil Awareness Campaign to promote these four core principles of soil health management:
- Keep Soil Covered. Covering the soil with cover crops or organic mulches—straw, for example—protects it from erosion while also moderating swings in temperature, slowing runoff, and promoting rainfall infiltration. These practices have the added benefit of suppressing weed growth.
- Minimize Soil Disturbance. This includes both physical disturbance, such as plowing or tilling, and chemical disturbance, which can harm microbes, fungi and other helpful living things. “This proactive measure can heal and protect properties of the soil and ultimately enhance the biological component of soil life,” according to the campaign.
- Maximize Living Roots. Using cover crops and other strategies for keeping roots in the ground throughout the year fuels biological activity, aids nutrient cycling, and contributes to improved soil structure.
- Energize with Diversity. Growing a diversity of crop species will enhance the biological, chemical, and physical properties that define soil health, improving the whole soil system.
Whether you’re maintaining hundreds of acres of croplands or a garden patch in the back yard, following these principles will help make your soil more productive and save precious resources.
A Special Podcast for World Soil Day
Just in time for World Soil Day, which was observed on December 5, the campaign released a special episode of its podcast series featuring Ira Wallace of the Southern Exposure Seed Exchange in Louisa County. Author of such acclaimed books as The Timber Press Guide to Vegetable Gardening in the Southeast and the state-specific Grow Great Vegetables series, Wallace emphasizes the importance of allowing no soil to go bare. She describes a range of options for keeping soil covered, among them planting cover crops such as buckwheat, adding organic mulches such as shredded tree limbs, and using tarps to kill underlying plants, which can be incorporated back into the soil when the tarp is removed.
Wallace also highlights the value of organic matter for making nutrients available to plants, for retaining moisture when conditions are dry, and for allowing water to infiltrate and move through the soil when there’s a deluge. She describes the transformation of the soil in her farm community from red clay to “brown gold,” thanks to decades of adding organic matter and keeping it there.
In the same episode, Professor Rory Maguire of Virginia Tech’s School of Plant and Environmental Sciences looks back at the farming practices that led to the Dust Bowl and points out that soil disturbance should be minimized to protect soil structure, prevent erosion, and ensure proper water absorption.
Ira Wallace is among the leaders in the soil health movement profiled in the 4 the Soil Campaign, which aims to raise awareness of soil as an “agricultural and natural resource critical to social, economic, and environmental health.” In addition to highlighting the four principles, the campaign’s website provides a soil health factsheet and a page of tips and resources that includes an interactive infographic and links to informative videos and webinars.
Join the Soil Health Movement
Kicked off this past June, the campaign encourages farmers and gardeners to take the 4 the Soil Pledge and promise to adhere to the four core principles of soil health management. The site also offers growers the opportunity to join the movement as a 4 the Soil Ambassador, providing tools for promoting the four principles on social media and through other outreach channels.
So, check out the campaign, take the pledge, and join the farmers, gardeners and conservation leaders who are working to ensure that our soil resources remain healthy, productive, and resilient—today and for future generations.
Resources
Soil Health: The Next Frontier of Conservation, from the USDA Natural Resources Conservation Service
https://www.nrcs.usda.gov/wps/portal/nrcs/main/va/soils/health/
Managing Soil Health: Concepts and Practices, from Penn State Extension
https://extension.psu.edu/managing-soil-health-concepts-and-practices
Soil Health, from the University of Maine
https://extension.umaine.edu/agriculture/soil-health/
Soil Health and Cover Crops, from Virginia Cooperative Extension
https://ext.vt.edu/agriculture/soil-health.html
