The organic soil is the foundation of organic plant growth. The base for a beautiful, healthy lawn is soil. Many homeowners do not consider soil composition as a potential threat to the health of their grass. But more often than not, many grass problems can be attributed to unhealthy soil. The concept of organics has to do with enriching the soil and increasing soil flora. In nature, nutrients enter the soil as organic matter is broken down by soil microorganisms. Therefore, the philosophy behind the use of organics in lawn care is simple. In feeding the soil, you feed the soil microorganisms, which in turn, feeds the plants.
Healthy soil is home to billions of microorganisms that feed on organic matter in the soil. Organic matter could be leaves, grass clippings, manure, buried wood, shed grass roots, or almost any biodegradable material that enters the soil. As the microbes feed on the O/M, they release nutrients in a form that plants can take up through the roots. Nitrogen is one of the elements released and the element consumed by grasses in the greatest amount.
Both, natural organics and most synthetic organics must have microbial activity to release nutrients into the soil. In fact, soil microbes are so important to plant health, that without them, the soil is thought to be dead. In nature, plants cannot live without them.
Test your soil
The first step is to test the soil’s pH – it should read between 6.5 and 7.0, which is slightly acidic. Soil that is too acidic will need a sprinkling of lime; sulfur can be added to soil which is not acidic enough. You can buy a pH tester for $40 – $60. Another solution is to have your soil tested professionally; first call your extension office – they often provide soil testing as a free service.
A soil test will determine the amount of organic matter that is currently in your soil. What the soil test doesn’t tell you is how much of the O/M is consumable by soil microbes. A supply of fresh organic matter in the form of organic lawn fertilizer will keep microbe populations high and healthy.
Soil Testing Steps
The next step is to find out if your soil is healthy with soil testing. A soil test is used to determine the pH, nutrient levels and soil type.
Start at the County Extension Office or a local garden center to obtain a soil test kit, costing around $10-$15.
Choose 20 test locations, taking sun, shade, pet areas and shallow foundations into account.
With many test locations, your soil testing results will more accurately gauge soil health.
Dig soil out with a small shovel or spade. The soil samples need to be 4-6 inches in depth and a couple inches wide.
Lay each of the 20 soil samples on a newspaper to air dry. Once dried, thoroughly mix the sample and fill the soil test container.
Send or take the sample containers to the soil testing facility for results.
Understanding Soil Testing Results
Below is a breakdown of soil testing results! These results will include soil pH level, soil nutrient levels, soil type. All of which play an important role for a healthy lawn.
Soil pH
The soil pH scale runs from 0 to 14. Neutral is 7, the middle of the scale. Any number below 7 means acidic (sour) and any number above 7 means alkaline (sweet).
Most flower, vegetable garden plants and grass prefer a slightly acidic soil. If you aim for a pH between 6 and 7, most soil nutrients will be available for absorption by the green life.
With too much acid or alkaline in the soil, nutrients will not dissolve to later be absorbed by the plant roots.
How to Fix Soil pH Problems: If you find that your soil is too acid, you can add ground limestone to make it more alkaline. If your soil is too alkaline, you can amend it by adding sulphur, shredded leaves or peat moss.
Soil Nutrients
Soil nutrients are just as important as soil pH. Nitrogen, the most important nutrient for supporting plant growth, will not necessarily be listed in your soil test results.
The nitrogen content of soil changes so rapidly that it’s not helpful to report what the number may have been on the day soil samples were taken.
The most helpful information from the soil test results are soil type.
Ideally you will have a loamy soil mix with phosphorous, potassium and other nutrients.
How to Fix Soil Nutrient Problems: Adjusting soil to create a loamy soil texture can take several growing seasons. To change the texture, add compost and work it into the soil several inches deep, over several seasons.
To Choose the Best Lawn Soil Composition
Lawns grow best in loamy soils that have a mix of clay, silt and sand. Too much clay in the soil mix, or heavy use, can compact the soil and prevent air and nutrient flow. Compacted soil may need aeration, a process of lifting small plugs of turf to create air spaces in the soil. For best results, rent an aerator or hire a lawn service to do the job – this will remove “finger size” plugs which improves aeration. Aeration is best done before top dressing and fertilizing.
Sand is the largest soil particle. Sandy soil drains well, is quick to warm up in spring and easy to cultivate. Sandy soils, however, don’t retain water well and dry out quickly. Even though plant foods tend to wash out, it can be a productive soil with careful management.
Silt is a soil particle that is smaller than sand but larger than clay particles. It feels smooth and powdery.
Clay is the smallest soil particle. Clay soil is sometimes called heavy soil because it is sticky when wet and retains water and contains a lot of nutrients.
Organic matter, such as compost and grass clippings, will benefit any type of soil; it lightens soil which is heavy in clay, and it builds humus in sandy soils, which helps retain water and nutrients. Some lawn mowers are equipped with mulching attachments which break up the clippings and disperse them as you mow.
Soil Layering
Newly built homes or new lawns may experience soil layering issues. This occurs when the top soil is scraped away for construction, and then a thin layer of soil is put back before planting the new lawn.
The finer soil layer on top of the coarser textured soil can prevent roots from taking hold, making it difficult for water and nutrients to penetrate the soil structure.
How to Fix Soil Layering Problems: Aerate the lawn this spring to blend soil layers letting in water and nutrients.
Understanding your soil is just the first step to an overall healthy lawn.