What’s the Dirt on Soil?
DIRT OR SOIL?
Although we often use the words dirt and soil interchangeably, the differences between them are vast. Dirt is made up of clay, sand, silt, and rocks, with no beneficial nutrients or microbes. Dirt is dead. Soil on the other hand is living. In fact, it’s teeming with life.
Soil holds the key to creating a sustainable garden, trapping and storing carbon, and providing a home for the billions of microorganisms and tiny creatures that help to maintain the health of the planet. Things that dirt just can’t do. Improving soil quality is perhaps the most important task of today’s gardener. Healthy soil provides plants with the nutrients they need for strength and to withstand significant changes in the weather.
Soil scientists, known as pedologists, divide soil into three main types:
- Sand, with its gritty texture, drains well and is easy to plant in but it lacks nutrients and as a result, needs to be amended.
- Silt has a soft texture that holds water well, but drainage can be a problem.
- Clay soil is sticky when moist and forms ribbons when manipulated in your hand. It is easily compacted and can be rock-hard when dry.
HEALTHY SOIL, PROSPEROUS GARDEN
Pedologists and gardeners alike agree that loamy soil, made up of an equal combination of all three soil types (sand, silt, and clay) is ideal for most plantings. These experts will tell you that healthy soil produces healthy plants. So, if you’re a gardener seeking success, it’s important to know the soil types throughout your garden including the macro and micronutrients, as you may have different soil types in different garden areas.
Most home gardeners concentrate on the top 4-10 inches of soil since perennials and annuals usually fall into this soil depth. For lawns, the focus is on the first 4-6 inches which house most of the roots. As you can imagine tree roots go beyond the top layer, 2-10 feet or more depending on the age and type of tree.
You can determine what your soil consists of by getting it analyzed. Here are three programs that can help you.
- Contact Virginia Tech (soiltest.vt.edu). Cardboard kits are available from our Association’s office at 3127 Forge Road, Toano, VA 23168. Stop by and pick one up. Instructions are on the box. For questions contact our Help Desk at 757-564-2175.
- Contact Turf Love. They perform the soil sampling as well as lawn measuring for you. There’s more information on our website (jccwmg.org) under Home Visits.
- Or for a personalized nutrient plan for your yard, especially if you live near the Chesapeake Bay Water Shed, contact Colonial Soil and Water Conservation District’s office, (colonialswcd.org).
HEALTHY SOIL STORES CARBON, LOTS OF IT!
Healthy soil helps store carbon from the atmosphere. If not for the sequestering of carbon in the soil, it would return to the atmosphere as carbon dioxide (CO2), the main greenhouse gas causing climate change. Most scientists think that soil has the capability for storing many more billions of tons of carbon than it does now (climate.mit.edu).
SOIL LOSS IS A BIG CONCERN
According to the World Wildlife Foundation, “half of the topsoil on this planet has been lost in the last 150 years. The effects of soil erosion go beyond the loss of fertile land. It has led to increased pollution and sedimentation in streams and rivers, clogging these waterways and causing declines in fish and other aquatic-related populations. Erosion also degrades large swaths of land, making them less capable of holding water which in turn, worsens flooding.
Preventing erosion and soil degradation are key parts to solving the overabundance of CO2 in our atmosphere that is contributing to climate change. Each of us can do our part by growing sustainable gardens, planting trees, and staying informed on the status of this problem. Check out Homes and Gardens, wildlife garden ideas, and the Amerian Horticultural Society-Soil Health for agricultural solutions that promote a healthier planet.