If you’re not getting the results you’d hoped for from all areas of your organic garden, it may be time to do some soil sample testing.
I’ve talked about simple home soil tests before. There really is a lot you can see with your eyes or smell with your nose or feel with your fingers.
But sometimes the only way to get the real goods on your soil’s nutrient profile is to do some soil sample testing and send it to the experts.
In fact, it’s a great idea to get a soil test done by a good soil lab right when you’re beginning a garden, in spring or fall, and then every year or two after that if you can, but it’s never too late to start.
A lot of people skip this step, and then have to play catch-up later because they made less-than-stellar fertilizing decisions based on guesswork...
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Phil: Hey guys it’s Phil from smilinggardener.com, if you haven’t checked out my free online organic gardening course, you can do that right on the home page of smilinggardener.com.
Today we are moving onto soil sample testing through a soil lab. This is a step that most people don’t do that is so important if you want to grow really healthy nutrient dense mineralized food or if you want to have all your plants be free of pests and ever have to spray anything ever again. This is a very important step to doing that and here is why it’s important. What most gardeners will do is they will get, they will use a lot of composed if they are specially, if they are organic gardeners, get a lot of composed on there. It certainly does have some nutrients and if it’s a good composed and then they will also use some fertilizers, especially NPK fertilizers, nitrogen-phosphorus-potassium or maybe some kind of more of a broad spectrum fertilizer but really when you are doing that you are guessing as to what your soil needs and the chances are extremely good that you are putting some minerals on there, your soil already has too much of and that maybe you are not adding certain minerals that your soil really needs.
So, it’s just like in the human body, we need to get a certain balance of all the minerals in the soil in order to have healthy food and in order that’s the two main things I always think of, healthy food pest free plants. So here is how I take a sample, first I clear off any organic debris any mulch and then I want to take a sample starting at the surface and going down 6 or 7 inches.
So, I do that with a very clean shovel, I don’t want to have a rusty shovel just like I don’t want to have a rusty pale that I put this in because that will influence the soil results. So I go down in there and you are sometimes what I do mix a little easier is I will pick that first shovel and kind of throw it aside, in that way it makes it much easier to take just a slice because I really want to get the full depth of soil down to 6 or so inches, then when I have that I put it into my very clean pale and that pale didn’t have any fertilizer or salt of anything in it because that would also affect the results.
One really important part of this year is to take samples from a few different spots in your garden. If you have a really weird spot in your garden you would I either leave that out or test it separately but for all your garden parts, parts of your garden that are the same, take a few samples and mix them together, that way you are going to get a more representative sample of your garden. Mix them together in here, they you just take a couple of cups put it into a zip lock bag, send that off to the lab.
When it comes to soil labs, you can go with your local lab and may even have some local knowledge but what I found is that there are almost always chemically minded, they are coming at soil from a very conventional way which is very different than organic.
So what I do is I ship soil sample to an organic lab, the two I often recommend are crop services international and international egg labs but there are a lot more. It’s a little harder you know in the US you can find a lot. It can be a little more difficult in other parts of the world including Canada to find a good lab but if you can find them where they are giving organic results that’s wonderful. I have a little bit written, more written in the article below about some other things I look forward in a lab so you can read that help you find a really good lab.
If you have any questions or doubt about soil testing, you can ask them down below and I will answer them. If you are on my website and you haven’t subscribed to my free online course here you can do that down below. If you are on Facebook, you can click the like button that is of course if you like and if you are on YouTube you can subscribe up above and I will see you next time.
For example, a lot of gardening information recommends using a lot of nitrogen and potassium.
This can cause all kinds of problems - it’s really calcium and phosphorus that more people should be using.
But only a soil sample test really tells you what you need.
Or many organic gardeners focus exclusively on adding organic matter and compost, and never take the time or spend the money to find out if there are specific nutrient imbalances that throw the delicate dance of the soil life off kilter.
It’s really worth the small investment to do some soil sample testing to get some more detailed information before you decide what to feed your soil.
So how do you take a good soil sample? You basically want to get... well, a good sampling of all the soil in your garden...
Most backyard gardeners probably won’t want to pay for separate analyses for each area of their garden, so the best way is to mix soil from several different locations, leaving out any really weird areas that would skew the results.
How to actually get the soil sample for testing? In at least a few different areas, dig a hole and then use a clean shovel to take a vertical slice of soil from the side of the hole, from the surface right down to about 6 inches.
After blending all the samples together thoroughly in a clean bucket, put about 2 cups into a clean container to send to the soil testing lab...
I love to use a local soil analysis lab if possible, but good soil labs are not as widespread as you might think, in spite of the increasing numbers of people doing organic gardening.
Most of the labs out there still have a chemical mindset when it comes to making fertilizer recommendations.
Think of it this way.
If MI6 needs to know which evil villain is secretly smuggling spent uranium rods out of a military dictatorship in a bid for total world domination, they call on 007, not on the local private eye that Q ran into down at the pub.
So it’s important to choose a soil testing lab that uses the right kinds of tests, mainly a base saturation test and perhaps some kind of weaker acid test.
We also want a soil lab that’s dancing to the same fiddler as us when it comes to organic practices, a lab that focuses on organic.
If your local soil lab happens to fit these criteria, look no further. But if not, you should probably go a bit farther afield.
The two labs I use most are Crop Services International (CSI – coincidence? hmm…) and International Ag Labs.
A test should cost $50-75, including their recommendations for which fertilizers you need.
You could even pay as little as $20-25 if you can learn how to interpret the test yourself, which does take some knowledge and a bit of math
(I’m actually going to be filming how to do this interpretation for the Academy this year. I wasn’t originally going to, because a good soil lab will give you good recommendations, but it’s a useful thing to know how to do and it can save you money.)
Ask me your soil testing questions below, or please share any other thoughts you have to add to the discussion...