The Importance of Soil Testing

Good soil grows grass. Is your soil good?

Beakers of soil
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Why Soil Testing?

Knowing the nutrient content and pH of your soil is the first step of a working lawn care program. Lawns are grown on a wide variety of soil types and fertilizer requirements can vary greatly depending on what's going on in the soil.

Many nutrients tend to be over-applied resulting in imbalances in the soil and harmful effects on the environment. An excess of nitrogen can cause leaching and groundwater contamination or contamination of waterways from run-off. Many current fertilizers no longer contain phosphorus because it binds with the soil, and years of needless applications have virtually eliminated the need to apply phosphorus to a lawn ever again.

What is Soil pH?

A soil's pH is the measure of its alkalinity or acidity based on a scale from 0 to 14. Zero represents harsh acidity, fourteen is extreme alkalinity, with seven being neutral. The pH of a lawn's soil should be in the 6.0 - 7.5 range. If pH becomes imbalanced, it can directly affect the availability of nutrients in the soil. Limestone derived products are applied to soil that is acidic(sour), while alkaline(sweet) soils require applications of sulfur products. Adjusting the pH of your soil may take several years but is crucial for proper nutrient uptake and plant health.


How to Get Your Soil Tested

You can get soil tested through your local cooperative extension offices, independent laboratories and some garden centers. It is inexpensive (around $10) and provides a wealth of knowledge.

  1. To Take a Soil Sample:
  2. Use a trowel, shovel, soil probe, sampling tube or soil auger
  3. Sample to a depth of 4-6 inches
  4. Remove any grass, thatch or debris
  5. Take 5 or 6 samples, mix them thoroughly in a plastic bucket and ensure you have approximately 1 pint of soil
  6. Spread over newspaper and let dry 24 hours. Labs prefer dry soil but don't worry if some moisture remains
  7. Label sample and send to cooperative extension, lab or return to garden center

The results will provide recommendations to correct any fertilizer deficiencies and pH adjustments allowing a more comprehensive approach to fertilizing the lawn