Organic Gardening Soil Improvement and/or preparation Soil Test

Soil Test — the Pros and Cons

In my first decade of gardening every time I read about a new “organic” soil amendment or fertilizer I could hardly wait to try it.  Whatever it was — always seemed just the right thing that I “might” need. (“Might” is the key word  there — no definites.)

Adding things to your soil that increase or decrease minerals like calcium, magnesium, potassium, phosphorus and other elements that you don’t know for sure needs to be done — is flawed thinking.

At least I was in good company – because that’s exactly what many gardeners do — especially new gardeners.

If you don’t know all the details about what you’re adding — you’re better off not to add any amendments.  (Stick with adding organic materials that decompose and make organic matter <humus> and you can’t go wrong.)  Adding other stuff without knowing exactly how much you need can make things worse in your garden rather than better.

Soil Tests

In the last year I’ve heard more and more about soil tests.

I had seen several results of lab soil tests posted on a forum and I wanted to learn more about these labs, how the tests were done,  how accurate they were, and how the gardener would go about reading the results. So I started researching a bit.

One reason that is promoted to get people to get a soil test is “it will tell you exactly what you need.”  The concept is excellent. Now if it were just all that easy.

My end conclusion is that I’m not getting a soil test — and I wouldn’t be getting one even if I were a new gardener with unimproved soil.  But I thought you might find it helpful if I shared some of my findings with you to help you determine whether or not you may want one.

Some of my Findings

Home testing kits:

As might be expected most home soil testing kits are inaccurate and of little value.  There is one that some farmers use that costs about $700, but even if it were accurate that doesn’t make sense for the home gardener.

Lab testing:

As you may not expect — soil tests done by a lab are also inaccurate.  Their results are rough estimates because of all the factors that have to be taken into account. It is said that soil consultants use them to successfully improve soils for their clientele — but I wonder how the home gardener fairs.

Reading the Results

I feel sure there are probably lab workers, soil scientists and some experienced soil consultants who feel very comfortable with reading the results of a lab performed soil test.  They might really have a handle on things like Cation Exchange Capacity and the balanced ratios of nutrients required in healthy soil.  (And by the way — each lab has a slightly different approach to what they consider the optimum balance of nutrients to be. Thus, obviously, soil test results will vary from one lab to another.)

I realize that all that is very important.  But it’s all a bit too complicated for my tastes. (I’ve always let nature do all that for me.)

Why not ask the Lab folks?

Now you might be thinking – “why not ask the people at the lab” for help on reading the results and what to do to correct whatever problem they say exists.  And you “can” do that.

  • Majority of labs:

Just keep in mind that the majority of labs are geared towards conventional agriculture which means they have a chemical mindset — which in spite of the overwhelming proof out there of it’s failure — continues to be dominated and promoted by big agri-business.  So in most cases — the lab is going to tell you what chemical you should add — and that, of course, is definitely not the right course of action to acquire great living soil that will grow healthy crops.

  • Some labs:

Some labs now offer organic recommendations second to their chemical recommendations. (I guess because organic is becoming more “in”.) To me — that shows their mindset is still conventional (chemical oriented) and I’d rather not take their recommendations either.

  • The minority labs — the ones you want. (I’ve only named two below but I’m sure there are more to be found. You can usually tell their mind set by their website.)

#1 -There are labs like Crops Services International (CSI) that work with organic and biodynamic farmers and use testing methods that are considered the best by folks who are suppose to know.

The CEC (Cation Exchange Capacity) test and the LaMotte test are generally recommended.  Together those two tests run about $52. Help with trouble shooting is $70 per hour.  Phone consultation if $1.00 per minute with a minimum $25 charge.

There is NO charge however to call and get recommendations for the tests you need.

#2 – Another lab that helps organic and biodynamic farmers is International Ag Labs. They give soil analysis with recommendations although they use a different method to obtain the test results.

They list the type of test and price here  but unless you really understand the lingo you’d have to call to get a recommendation on what tests you need for your goals.  Price is basically the same as CSI.

I understood that recommendations made with test results from them are included in the price of the test.  If you want special consulting they probably charge an additional fee, but I didn’t see that on the website.  You could ask when you call for test recommendations.

International Ag Labs has a special website for backyard gardeners called

What is Brix? When the term Brix is used regarding plants —it is referring to the measure of carbohydrate levels in the plant juices.

The only thing you need to remember is that generally high Brix food has greater mineral density and therefore is more healthy. (Although — I’ve read of certain tests that indicate that is not necessarily 100% true all the time.)

High Brix in the fruits and vegetables that we produce in our gardens is what we want. Even if you don’t want a soil test, this special page is worth a read.

My Preferred Method of Correcting Soil

It has been my experience that if you practice the principles of nature:

  • consistently adding organic material that break down and become organic matter (humus) in the soil,
  • mulching your soil,
  • diversity in your crops

in time nature will correct the soil for you. That is my preferred method.

You can pretty much tell when your soil is great by looking at it. (We’ll go into more on that in a future post.)

My Opinion of When a Soil Test Would be a Good Investment

I can see where the investment of having a high quality lab help you sort out the problems  inherited with abused land that has been ruined by conventional agriculture can put you a year or two ahead. I am speaking mostly of farmers and market growers, although in some cases this may apply to the backyard gardener.

How to Take a Soil Test

(quoted from

Take a sample by digging a vertical hole to a depth of 6 inches. Take an even slice off the side from top to bottom with a clean spade and put into a clean bucket. Take several samples like this throughout the garden or field. Once all samples are collected, mix soil thoroughly and take out 1 1/2 cups of soil. Soil may be submitted in soil sample bags or plastic Ziploc bags.

Stick with the Lab you Choose

If you want to make comparisons each year, stick with the lab you choose since each has a different way of doing things and the results of the test will be based on their way of doing things and will vary from another lab.

Final Thoughts

I hope this information has been helpful to you if you’re thinking of having a soil test.  And if you were not thinking about it — it’s still good to know a little about the pros and cons of the subject.


Organic Gardening is easy, efficient, effective and its a lot healthier.


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  • What a comprehensive article Theresa. I will get the chance to prove you right this year. After adding lots of organic matter, cover cropping and keeping my soil mulched, I will again try tomatoes in the beds where I had my spectacular failures 2 years ago. Maybe I should wait another year, but I’m short on space, and we will see. I am guessing that not watering, keeping the mulch on, and the improvement to the soil will do the trick.

    Oh, by the way, I did have a soil test, and all I got out of it was a giant headache and a shopping list for strange stuff that I would have to keep out of reach of the kids!!!!!
    I’m looking forward to reading more about Brix.
    Thanks for your work on this – very well researched.

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