Looking at basic soil test results

You’ve read it here in this blog, you’ve heard it from your neighbor, even your Aunt Bootsie told you to get a soil test for your garden.  I’ve always recommended using the soil testing lab at Michigan State University, it’s the “gold standard” of soil labs in Michigan. For most gardens a basic test will provide you with all the information you’ll need.

In past blogs I’ve described how to properly take a soil sample for testing and what to do with it once you’ve collected it, so we won’t discuss that today. Instead we’ll look at actual soil test results.

Once you’ve rounded up a bag of dirt, sent it to the lab along with your payment, the MSU soil lab will test your sample, processes the results and send you the test results either by email or by mail. That usually happens within ten days.

Let’s take a peek at an actual soil test readout I received last fall.

Results from a soil test
Results from a soil test

The first test result is the soil pH. pH describes how acid or how alkaline your soil is with “7” being neural. In this case the sample result is 7.6 which is somewhat alkaline. So right away we know we won’t have to add any lime to raise the soil pH since most garden plants grow best in a slightly acidic soil.

Next is the result for phosphorus, the “P” in NPK. The result came back at 58 ppm (parts per million) which, according to the graph is well in the optimum range.

Following P we see that is the potassium (K) is 67 ppm which we see is below optimum. Magnesium (Mg) at 202 ppm is above the optimum range.

Calcium(Ca), shown in the additional results section is 2443 ppm which helps to explain the relatively high soil pH reading since calcium will raise soil pH.

The next result is CEC (cation exchange capacity) this tells us how well the soil is able to retain soil nutrients. A reading of 14.1 tells us we can add fertilizer to this garden without having it leach out of the soil. Usually, soil types with a higher percentage of clay in their make-up have a higher CEC and therefore are inherently more fertile because of all the retained nutrients. Very sandy soils have low CEC values. It is very difficult to change the CEC of a soil. On the other hand, we can easily raise the NPK values by simply adding fertilizer.

Those cations (positive-charged ions) that are being described in the CEC reading are mostly K, Mg and Ca. There is a section in the readout providing the percentage of each of those. Phosphorus is not listed there because it exists in the soil as negatively charged anion (PO4 3-).

Nitrogen (N) is not tested for at MSU because soil nitrogen levels change with the temperature and other variables so you would never get an accurate reading.

We don’t have room here to discuss the soil science behind the results. Fortunately, the soil lab boils it all down to some simple recommendations at the bottom of the readout.

The nutrient needs are listed as actual pounds of each element per 1000 square feet. Since fertilizer is not sold as pure nitrogen, phosphorus or potassium, the precise amount of any type of fertilizer must be mathematically calculated. Back in the olden days when I was an MSU Extension Agent and the results were printed with a dot-matrix printer, I made those calculations by hand on hundreds of test results. Nowadays MSU has an online calculator that you can use to figure out how many pounds of fertilizer you would need to apply.

With the planting season rapidly approaching,I suggest you get your soil sample to the lab ASAP. Much like your income tax return; the sooner you send it in the sooner you’ll see your results.





Gardening in a post-apocalyptic world

“Because survival is insufficient”

Last week I had the pleasure to participate in a panel discussion sponsored by the Agora, the student newspaper at Monroe County Community College. It was part of their “One Book One Community” series in which a book is chosen and as many people as possible read the book, then events such as panel discussions are held.

This time the book was Station Eleven  a post- apocalyptic novel written by Emily St. John Mandel.  The story is set in the not-to-distant future Great Lakes area, so it has a special attraction for those of who live in this area. An extremely virulent influenza virus has abruptly wiped out over 99% of the world’s human population causing complete collapse of civilization. A performance group called the Travelling Symphony wanders about the shores of Lake Michigan and Lake Huron performing Shakespeare for villagers.

You'll recognize some of the vaguely familiar locations in Station Eleven
You’ll recognize some of the vaguely familiar locations in Station Eleven

Our panel discussion addressed hypothetical questions of how would we survive a catastrophic event and the chaos that would follow. On our panel was Micha a sportsman who is an expert hunter and fisherman; Chase, a young, decorated war veteran who gave his thoughts on self-defense; our director of emergency management Mark Hammond representing the government’s point of view; my wife Judy — who is a retired horticulturist from Matthaei Botanical Garden– and myself shared our opinions on growing and preserving food.

A number of possible scenarios were brought up ranging from a natural or man-made electro-magnetic pulse that takes down the electrical grid to a global pandemic much like the one in Mandel’s novel and everything in between. Most agreed that the most probable disaster would be an electrical grid failure that we could recover from in a relatively short period of time. This was not long after the wind storm in March that knocked out electricity to over a million people in Michigan so it was still fresh in everyone’s mind.

What are three things that you should do right now to prepare for a disaster? There are many possibilities but our Mr. Hammond suggested we look at the FEMA website to get started and always have a “bug-out bag” ready.

Learning the rudiments of hunting and fishing would serve you well in the Great Lakes area if you were lucky enough to survive the beginnings of an extreme disaster. Purchasing proper outdoor equipment, including firearms, ahead of time and learning how to use it is critical if you decide to prepare for that kind of eventuality.

In my opinion, subsistence gardening/farming would be the most productive endeavor in a post-apocalyptic world, especially you decide to settle in down in one spot and not travel. My suggestion to the audience was to take up gardening as a new hobby to learn how to grow your own food. Judy reminded the participants that most garden seed is only viable for one to five years, depending on the type of vegetable and open-pollinated, heirloom varieties would be the only workable option for growing food long into the future.

We all agreed that it would be best to have a group of like-minded family and friends who could band together to share their skills to help mitigate the worst aspects of a disaster. Even some form of entertainment would be welcome. Many years ago a group of my friends discussed that very topic: who would be critical to the survival of the group? After all the practical skills were covered, like woodworking, blacksmithing and such, it was decided to include Greg because he was a talented guitar player and wonderful singer.

Even if civilization is not wiped out during our lifetime, gardening is a healthy, enjoyable, productive hobby.