Soil Health Vs. Soil Fertility

Published Mar 20, 2018  

In the 52 Weeks of Agronomy Series I've been posting on my website, I took a week and explained this agronomist's take on soil health vs. soil fertility. To read the article and get caught up on the rest of the series follow along at 

I spoke at a conference in front of 200 farmers and used the term, custom soil fertility programs. At the time I was working as a sales agronomist for a fertilizer company that offered custom fertilizer recommendations based on a farmer’s soil tests. As far as I knew this was pretty standard for the industry. Not a big deal if you asked me.

After my talk, I headed back to my table to see a line of guys with soil tests in their hands. Jokingly I made a comment how funny it was the line was so long and wondered what all the fuss was. Someone in line commented “As soon as you said the word fertility everyone woke up and started looking at you. You smiled and started to blush. You made fertilizer sound sexy.” Not the intention behind my talk but, I took it as a positive and was excited about the opportunities that it had lead too for the company. Plus, I got to look at a lot of soil tests, and I geek out over that.

However, when I told the story to the non-agronomists in the office, they didn’t see it that way. They explained to me that that was not the image they wanted to convey to the public. I was to use the term soil health, not fertility. I thought to myself, aren’t you a fertilizer company? I talk like that when I’m around all my agronomist friends, and they don’t get upset. It seemed to make perfect sense to me. Then It dawned on me, every occupation has a certain language, and it can get confusing to someone who doesn’t always use it on a regular basis. I have to be honest; I don’t always use the two terms correctly either. Soil health and soil fertility are two separate topics and I have found can get overused, used in the wrong context, miss-used, and obviously misunderstood.

In my agronomy mind….

Soil health refers more to an overall concept regarding the qualities of soil to function as part of a system successfully. It's a measure of the overall ability to support what is growing in it continually while balancing the biological, chemical, and physical attributes of the soil. Notice, I said balancing. As a grower, you need to realize that the chemical attributes of the soil are a by-product of the physical and biological. You need to maintain the balance of all three to have a healthy, resilient, and efficient system. You have some tests done; you tweak a few things, you grow a good crop. Everything is running smoothly. Similar to me whereas overall I’m healthy. I get regular check-ups, the doctor says I could stand to lose a few pounds, but my blood work and tests come back good.

Soil fertility is what you are doing to achieve healthy soil and its ability to sustain the crop you are growing. It is the reality of it, not just the concept. Here is where the rubber meets the road. You use management practices, inputs, and choose crops that are realistic given the inherent abilities of the soil type you are working with. Some factors that influence soil fertility are soil structure, drainage and water holding capacity, soil biology, organic matter, pH, cation exchange capacity, and parent material. In the case of my health; it is me setting realist goals, eating healthy, and exercising regularly.

I’m not saying that the two ideas never intersect and are separate from each other. You need to consider the health of soil to manage the fertility and vice versa.