Building Better Soil

By Jillian Lowery, New Country Organics Farm and Garden Consultant. Luscious, abundant gardens such as the ones featured on Better Homes and Garden magazines are every gardener’s dream. Yet such beautiful success is not always a reality. A far more common reality is a garden that thrives for a few weeks only to end with struggling crops, lower yields, and an exasperated gardener. Successful gardens can be achieved, however, with closer attention and care of the soil. Healthy, productive soil makes for healthy, productive crops. In order to establish and maintain healthy soil, one must first understand the complex components with which it is created. Soil contains a vast, interconnected food web of microorganisms, earthworms, and other symbiotic elements. Plants contain mycorrhizal fungi, which are “the intricate associations roots form with specific fungal groups [that] represent the underground absorbing organs of most plants in nature” (Gianinazzi-Pearson, 1). These filaments interact with plant roots and surrounding bacteria to provide nutrients to the soil and to create a looser soil structure (Howard, 1). The carbohydrates released by the plants into the soil provide a nutrient-rich environment for the microorganisms teeming at the roots. Healthy topsoil can contain “600 to 800 million individual bacteria from a possible 10,000 species; several miles of fungal hyphae; 10,000 individual protozoa; and 20 to 30 beneficial nematodes from a possible 100 species” in just a spoonful of soil (Ussery, “Build Better Garden Soil,” 1). This complex ecology can be easily damaged, however, by poor soil structure or an imbalance of nutrients. In its basic elements, soil can be characterized as three distinct soil separates: sand, silt, and clay. These materials are derived from various parent materials of differing chemical compositions and ultimately make up topsoil (Ussery, “Build Better Garden Soil,” 1). Sand may originate from rock fragments or, more typically, from quartz, thus containing little in the way of plant nutrients (Brady, 167). Silt contains many similar properties to sand but has much smaller, finer particles that give it a silky smooth feel (Brady, 168). Clay contains the smallest particle size of these three separates and has a greater water absorption capacity and plasticity (Brady, 169). A mixture of these three separates in equal proportions is called loam. The arrangement of these particles makes up the soil structure and defines the soil tilth, which is “the physical condition of the soil in relation to plant growth” (Brady, 187). Organic matter is another essential component of healthy soil and is constantly being produced by decomposing plant matter, animals, and animal waste. The resulting material is referred to as humus. Energy from this decomposing material is harvested by various microorganisms throughout the soil that in turn provide nitrogen, enzymes, minerals, and other nutrients back into the soil for reuptake.  Many gardeners struggle to establish or maintain the right soil type and often make matters worse by adding the wrong elements in efforts to amend the soil. Thankfully, there are several ways to bring soil back to a healthy, thriving, and productive balance. Adding diverse sources of organic matter is a great way to naturally improve soil. Livestock manures are a good source of nitrogen and provide readily available nutrients to soil life (Ussery, “8 Steps for Making Better Garden Soil, 1). Composting recycles nutrients from organic wastes and increases production of humus. Compost is generally applied every spring at a rate of 1 inch deep (Howard, 1). Mulching also provides similar benefits to soil as composting but is less disruptive of soil organisms during application (Kent, 1). Because its nutrients are so readily available, typical mulch applications are only 2 inches deep (Kent, 1). Throughout the decomposition of mulch and other organic materials, earthworms and other microorganisms mix the resulting product into the existing soil, which improves soil tilth. Chickens are also a great resource to rotate through garden beds, as their scratching habits work the soil without the extreme disrupt of tilling practices. Minimizing tilling is important because it preserves surface-layer organisms, earthworm tunnels, and webs of beneficial fungi and prevents poor water drainage and compacted soil from buried plant debris (Howard, 1). Cover crops are also an effective means of adding nutrients back into the soil, preventing soil erosion, and improving soil structure and fertility (Ussery, “8 Steps for Making Better Garden Soil,” 1). The best soil will have a combination of what poultry farmer Harvey Ussery calls “the living, the recently dead, and the very dead,” which refers to live plant matter; the decomposition of soil organisms, compost, and animal wastes; and the final result of humus (Ussery, “8 Steps for Making Better Garden Soil,” 1). Once the organic matter has had sufficient time to incorporate into the existing soil, it is advisable to collect a soil sample for analysis prior to planting the next crop. Soil analyses pinpoint areas where the soil is deficient and can be tailored to the next intended crop’s needs. Additional soil amendment products such as a mineral mix, calcium, or soil conditioner may be needed to boost the soil. Once these things have been established, gardening methods such as companion planting and crop rotation will continue to build up and maintain the soil. As previously stated, healthy, productive soil makes for healthy, productive crops with the added benefit of a healthy ecosystem. With these practices and a better understanding of soil properties and the expansive life found within it, the dream of a successful garden becomes much more achievable. Works Cited Brady, Nyle C., and Ray R. Weil. "Soil Architecture and Physical Properties." Elements of the Nature and Properties of Soils. 14th ed. Upper Saddle River, N.J.: Pearson Prentice Hall, 2014. Print. Gianinazzi-Pearson, Vivienne. "Plant Cell Responses to Arbuscular Mycorrhizal Fungi: Getting to the Roots of the Symbiosis." The Plant Cell 8.October (1996): 1871-883. Web. 7 Dec. 2015. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC161321/pdf/081871.pdf Howard, Doreen. "Building Fertile Soil." Mother Earth News - The Original Guide to Living Wisely. Ogden Publications, Inc., 1 June 2003. Web. 7 Dec. 2015. <http://www.motherearthnews.com/organic-gardening/building- fertile-soil-zmaz03jjzgoe.aspx>. Kent, Kathy. “Mulch Works Miracles by Building Up Garden Soil.” South Bend Tribune (Indiana). 9 Aug. 2003. LexisNexis Academic. Web. 3 Dec. 2015. Ussery, Harvey. "Build Better Garden Soil." Mother Earth News. Ogden Publications, Inc., 1 Apr. 2007. Web. 8 Dec. 2015. Ussery, Harvey. “8 Steps for Making Better Garden Soil.” Mother Earth News. Ogden Publications, Inc., 1 Jun. 2007. Web. 8 Dec. 2015.