A strong foundation is important in many aspects of life. Giving children a strong foundation in the form of family helps them as they transition into adulthood. Sleeping on a mattress that is comfortable gives us the foundation at night for rest so that we may have prosperous day. Our homes literally rely on a strong foundation for their integrity.
A strong foundation is also vital for plants. The soil in which our plants grow provides moisture, nutrients and is the media in which the root system develops. Determining the available nutrients, how to stabilize the moisture level and understanding the structure of a soil are keys to ensuring the success of the plants in your yard.
Rich soil contains the primary plant nutrients nitrogen, phosphorus and potatassium (NPK). Those three nutrients along with seventeen other minor nutrients help fuel plant growth. Decaying organic matter and minerals within the soil provide these nutrients. Organic and inorganic fertilizers can supplement any deficiencies that may be present in the soil. The acidity level of a soil affects the availability of nutrients to plants. A pH level of 6.0-7.0 is best for most plants. Lime can be used to raise the pH of a soil. The pH of soil can be raised through the use of Aluminum sulfate. Soil testing information is available through the University of Illinois Extension Service website.
Keeping soil evenly moist is critically important to plant development. Many plants do not tolerate ‘wet feet.’ A soil rich in organic matter assists in providing plants with a growing medium that doesn’t hold excess water or dries out too quickly. Organic matter can and should be added to soil through peat moss, mushroom compost, gypsum, mycorrhizae, top soil and worm casings. Soil drainage can be tested by digging a hole that is 12” by 12”. Fill the hole with water and record how long it takes for the water to completely drain out of the hole. Ideally, it will drain out in 15-60 minutes. If it drains in less than 10 minutes, your soil would be prone to drought. If it takes 4 hours or more your soil is poorly drained. This may be due to a large percentage of clay being present.
An ideal soil composition consists of 25% air, 25% water, 45% minerals and 5% organic matter. It is important to protect the structural integrity of soil by being careful not to work in the soil if is it wet. Plant roots need access to oxygen in the soil to thrive. The soil still must offer enough structure to support the roots. Wet or dense soil suffocates roots, and overly aerated soil gives roots nothing to grasp, making the plants easily uprooted. Turning the soil before planting helps incorporate oxygen into the soil, as does the addition of organic matter such as compost and peat. The largest particles in organic matter break up clay and sand in soil, providing more space for aeration between all of the particles in the soil. The structure of soil can be tested through something called a ribbon test. Soils that won’t form a ribbon when rolled between your thumb and fingers contain at least 50 percent sand and only a little clay. Ribbons that break before reaching 2 inches long contain about 25 percent clay. If you can squeeze out a ribbon 2 to 3-1/2 inches long, your soil contains at least 40 percent clay.
A high-quality soil helps plants establish a healthy root system and develop abundant foliage, which leads to strong flowers, shrubs and trees. Its importance cannot be overstated.
Kathleen Carr is the owner of The Growing Scene, Inc., a landscaping company. She can be reached by calling 815-923-7322 or emailing her at Kathleen@thegrowingscene.com. Have a gardening question? Please contact her. She may address it in an upcoming column.
