Myth #1: The Myth of Soil Sterilization
from Synthetic Fertilizers

Myth #1 - Soil Sterilization: "Inorganic and synthetic fertilizers are killing microbes and sterilizing our soils. The result is that plants are becoming addicted to synthetic fertilizers". (Seen quoted in various articles)

While these statement may sounds reasonable, research has already proven the sterilization claim to be false. Our plants are not becoming addicted and our soils are not being sterilized. Here is why the sterilization of soils is considered a lawn myth?

Research Demonstrates the Opposite is True

My textbook entitled "Biology of Plants" tells me there are many millions of bacteria in the soil under your fingernails after working in the garden. Billions of bacteria if you include all the soil on your clothing, too.

Bacteria make up the majority of all soil microbes. These bacteria perform vital functions that are necessary for all plant life. In fact, no life on earth could exist without these microscopic life forms tirelessly doing their job. There is almost no force on earth that can permanently kill all microbes.

Yes, it is true that some substances can harm certain microbes. No doubt about it. It is very important to know that the same substances that can harm one type of microbe is dinner for another.

For example, an oil spill can harm many types of microorganisms, but the oil itself will slowly be digested by other types that consider the oil to be prime rib. It just doesn't disappear on its own. When the oil is broken down and consumed by oil digesting microbes, the microbes that were originally harmed by the oil will quickly return to normal.

Microbes live everywhere, in the water flows of melting glaciers to the geothermal hot springs resulting from volcanic activity.  The environment selects which types will survive. 

And again, the heating of compost material over weeks is designed to kill off most bacteria. The pathogens that can harm both people and plants is the goal of this action. Yet, compost is teeming with microbial life. 


What About Ammonium Based Chemical Fertilizers?

Contrary to popular belief, plants do not know or care where the nitrogen comes from. All the plant knows is that it is nitrogen. They will use them exactly the same way.

Maybe plants don't care, but what about the soil bacteria? Ammonium nitrogen will harm bacteria, right?

Yes, it can at first, but just like the oil spill analogy, the ammonium in the soil is broken down by the work of other organisms not affected by the nitrogen. As the ammonium breaks down the suppressed group of microbes start to recover. This is God's design and is light years away from soil sterilization.

Inorganic fertilizers still do and always will provide a benefit to us. However, having said that, it does not mean there are not good reasons for using organic fertilizers or natural lawn care. Organics provide a lot of benefit to both the plants and the soil microorganisms.

Just for Fun, Let Me Play the Devil's Advocate...

Just for fun, let's take this out to its logical conclusion.

To do this, let's assume the statement about soil sterilization with fertilizers were true. The implications are that microbe numbers do not bounce back when using synthetic fertilizers. What would it mean?

First, to clarify, the term "soil sterilization" means all microbial life in the soil is dead.

If your soil becomes sterilized, that means you have no soil microbes and no mineralization of elements taking place to support plant life. The soil could not sustain life on its own.

If this were true it would be a world wide problem of epidemic proportions. "Over 80% of all the ammonia produced in the entire world is used in fertilizers". Source: Wikipedia (Not a scientific source so you can take that for what it is worth)

Therefore, without soil microbes, out of necessity, you would need to become an expert in the use of fertilizers and in the way plants use nutrients just to keep everything alive.

You would have to supply all the nutrients the grass needs on a consistent basis and in the correct amounts whenever the grass needs it.

You would have to know which fertilizers to use and which ones to avoid, since most would be of little use.

Now get this: Even certain synthetic fertilizers will not work because they require the work of soil microbes before the nutrients can be released for plant use. (I bet no one ever told you that.) Do you know what synthetic fertilizer ingredients require soil microbes and which ones do not?

For example, you couldn’t use sulfur coated urea as a nitrogen source.  The problem is that soil microbes are required to breakdown the sulfur coating before the urea nitrogen can be released to plants. However, since no living microbes exist in the soil, the sulfur coating would never break down. This applies to many other fertilizer ingredients as well.

The bottom line: If the soil sterilization claim were true, to effectively feed your plants, all ingredients must be of the type that require water only (without microbe help) as a means of activation. Any requirement of soil microbes to effect the mineralization of nutrients will be of no use to your plants where no microbes exist.

Now you can start to see the absurdity of these claims.

You can test the soil sterilization theory yourself. If you know of someone who has been using synthetic fertilizers for a while and want to see if the grass is addicted or if his soil is sterilized, ask him to completely stop using fertilizer for a while. If his grass continues to do thrive and grow, this is your proof that the theory of soil sterilization is not true.


Myth #2: The Myth of Increasing Soil Microbes by Adding More
Microorganisms are the backbone of soil life. To increase the microbe populations we can simply add more via a commercial product or homemade tea, right? Not Necessarily! Find the truth about soil microbes and how they multiply.

Myth #3: The Myth of Using Gypsum for Lawns to Raise Soil pH

Gypsum for lawns is often used as a liming material to sweeten the soil. However, many people do not realize that it has no affect on soil pH. Find out why and what important function gypsum has in the turf industry.

Myth #4: Grass Cutting Height Does Not Matter

People love the look of a golf course. A common myth is that we can cut our lawn extremely low to get a golf course look. Find out why this can harm or kill your grass, depending on the grass species.

Myth #5: The Truth and Misconceptions About Fertilizer Numbers

Understanding fertilizer numbers are for geeks and professionals, right? Wrong. Knowing their meaning and how to use these numbers properly is the first step that separates the experienced from the inexperienced. Learn the misconceptions and the truth behind the numbers.

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