Friday, December 27, 2019

Remineralizing the Soil

One thing that I hoped would happen after I moved the ducks out to our acreage was that I would be spending more time out there and start to feel more comfortable being out there.  I suspected that without the daily draw of the ducks, I would not go out there much.  And I really wanted to put myself in a position to start really seeing the land and planning for a horse barn.

For once, my plans worked out really well.  Because I'm out at the acreage at least once a day, I'm starting to get the hang of the rhythm of the property.  I see what parts stay wet after a rain, which parts really need more soil brought in, and which parts I need to prioritize the next time I rent a brush hog.

I was so inspired by being out there that I ordered a couple of pear trees from a nearby orchard to plant at some point before March.  I also started working on diagrams of where other fruit trees might go as well as figuring out the possibilities for a garden.

As part of my interest in a garden, I remembered an ebook I had purchased quite awhile ago.  It covered the concept of a minibed garden on plastic.  When I first bought the book, I think I had been thinking of using the ideas within the context of the few raised beds I keep in my front yard.  But I ended up putting it away and not really doing anything with it.  Then, all of a sudden, I realized that the concept would be perfect for our acreage.  Unlike the yard at our house, which is uneven and slopes quite steeply, our acreage is reasonably level.  And unlike the yard at our house, which is populated with huge rocks, our acreage has no rocks, so it isn't so hard to plant and doesn't need raised beds to make gardening bearable.  Not everyone is crazy about the idea of using plastic mulch, but I have to admit that after many years of dealing with weeds that seem to grow a foot overnight, I'm ready to try something different.  I would rather get good food using plastic than lose most of my crop to weeds.

When I started re-reading the ebook, I knew I really wanted to try the concept out this coming spring.  I also happened to have another book by the same author, Herrick Kimball, called the Planet Whizbang Idea Book for Gardeners, and I skimmed through that one as well.  Kimball wrote about the concept of remineralizing the soil and he referenced a couple of books on the topic.  I found The Intelligent Gardener by Steve Solomon and The Ideal Soil v2.0 by Michael Astera to be fascinating reading.  One thing that disturbed me quite a bit was the analysis of the nutrients in an apple grown in 1914 as compared with one grown in 1992.  The amounts of Calcium, Phosphorus, Iron, and Magnesium were so much lower that I wonder what the point of eating an apple is.  The way farming has been carried out has damaged the soil so much.  The other thing that I really took away was that simply adding compost to your soil doesn't necessarily do much good.  Soil, especially neglected or mismanaged soil, is more complicated than that.  And if you want to grow nutrient dense food, it is important to pay attention to the nutrients in your soil.  You simply cannot expect to keep growing things and removing the harvest without putting something back in to replace what was lost in a targeted way.

I decided I wanted to put the information I'd read about to the test.  I ended up getting a soil probe, and my daughter and I went out one day to take soil samples with the probe, so I could have a soil test done.

Using a soil probe is harder than it looks!
I mixed up the samples we collected and sent off a package to the soil lab recommended by Astera.  I got my results back really quickly by email.  See below.

One of the most important numbers to pay attention to on the report is the Total Exchange Capacity.  I'll spare you the scientific explanation, but it essentially means how much fertility the soil can retain.  When I sent my results to Michael Astera himself to be analyzed and get fertilizer recommendations, he said that my soil was among the lowest fertility soils he'd ever analyzed.  That isn't surprising actually, because the soil on our acreage is composed of what is considered ancient clay.  This clay has been around for a very long time and with the high rainfall in our area, much of the minerals have been leached from the top soil.  And I already suspected the soil wasn't that good just based on what I've seen growing there, which is a lot of scrubby, brushy things.  These scrubby, brushy things probably have extensive root systems so that they can draw nutrients from the subsoil instead of the top 6-12 inches, which doesn't have much to offer.

What this means is that I have my work cut out for me if I want to make our acreage a productive place for growing fruit trees, a garden, and a horse pasture.  Thankfully, as long as I keep my soil improvements concentrated to smaller areas (like a half acre), the soil amendments that I need to add are affordable.  I really should have limed my field with what might seem like an excessive amount of lime already (1,750 pounds for a half acre!).  This high amount is partly to address the fertility issue, partly to address the pH issue, and partly to address low Calcium.  These three issues are likely connected to each other.  Plus, we have high rainfall, so anything I add will be leached quickly until the soil develops the capacity to retain it.

Typically liming is done in the fall so that the lime can leach through the soil a little before spring.  (And there is a chemical reaction that really needs to happen which takes some time and helps improve the soil's ability to accept additional minerals in the spring.)  Unfortunately, by the time I'd gotten the analysis from my soil test, it was a bit too late.  The ground was alternating between being frozen and wet enough to have standing water.  Neither of those conditions are appropriate for spreading anything.

So I will try to get it done in March, and I'll add the lime with all the other amendments and till it in.  I think tilling is not always recommended, but in my case, my soil is really hurting and if I want to try to grow anything on it besides brush and weeds, I have to get the minerals in the soil.  Plus, when I contacted a local feed store about purchasing lime, I discovered there was a study by Virginia Tech that found that it takes lime about a year to leach down through one inch of soil.  If you can't till because you have pasture or an orchard, you have to live with those slow results.  But I can till, so I can get minerals into the top six inches pretty quickly, although it will still take some time for the chemical reactions that need to happen in order for the soil to actually start improving.

I really like the idea of leaving our acreage in better condition than when we got it, so this spring you will find me behind a spreader and a tiller as I happily distribute minerals throughout my soil:)


  1. Please oh please keep writing about the soil stuff as you move forward with things in the spring! I find it so fascinating. =)

    1. I definitely will, Liz! I have no doubt that my plans will go awry at some point and I will have tons of lessons learned to share:)