Many people believe that soil and dirt are the same thing, but they’re not! Dirt is what you get under your fingernails, while soil is the then layer of living skin that covers the land. Soil is so much more than dirt. It’s alive!
Soil is a living ecosystem—a large community of living organisms linked together through nutrient cycles and energy flows. Every teaspoon of soil is home to billions of microorganisms. Bacteria and fungi break down dead plant and animal tissue which become nutrients for your plants. Nematodes eat plant material and other soil organisms, releasing plant nutrients in their waste. Specialized mycorrhizal fungi form symbiotic (mutually beneficial) relationships with plants. The fungi bring hard-to-reach nutrients and water directly to plant roots, and the plants provide the fungi with carbohydrates. Worms and insects shred and chew organic material into smaller bits bacteria and fungi can easily access. Garden earthworms burrow and create pathways in soil that fill with air and water for plant roots. A healthy soil ecosystem provides plants with easy access to air, water, and nutrients. So how can you encourage a healthy soil?
Understanding your soil is the first step to creating an optimum soil ecosystem. A soil test can help you do that. There are analyses that can give you information about soil texture, pH, nutrients, and organic matter, and provide fertilizer recommendations for the plants you plan to grow.
Adding organic matter is important. Organic matter improves soil physical properties such as air and water availability, allowing for healthy root growth. Organic matter is composed of living plant roots and organisms, decomposing plant and animal residue in varying stages of decay, and enzymes secreted by soil organisms that act like glue to bind soil particles. Highly decomposed plant material is called humus, a stable and important source of plant nutrients great for growing plants.
Air and water are essential to soil health. Plant roots and microbes need access to varying amounts of air and water for optimum growth. Thankfully, our soil is full of microenvironments—tiny habitats that differ in the amount of available air, water and nutrients. Soil compaction and disturbance such as excessive tillage can eliminate these important microenvironments. This makes it hard for plant roots to penetrate the soil, absorb water and nutrients, and interact with beneficial microbes. Disturbing soil also disturbs weed seeds, exposing them to light and increasing germination—in other words, more weeds!
Mulching and the use of cover crops can protect valuable topsoil from erosion and add rich organic matter as they decompose. Raindrops landing on bare soil can splash soil particles several feet into the air. Mulching bare soil around plants prevents the splashing of soil particles and soil-borne pathogens onto leaves and stems, reducing the occurrence of disease. Mulch and cover crops conserve soil moisture, minimize weeds, and reduce plant stress by moderating soil temperatures.
Healthy soil is an investment in your landscape! The beauty and healthiness of the plants in your landscape are direct results of the health of your soil. For more information contact us at 706-795-2281 or clh@uga.edu.