Replacing Soil Nutrients: A failure of Observation

Steve Solomon in Tasmania writes:

Friends,
I have put Tiedjens “Olena Farm” into the ag library at soilandhealth.org and am working on his “More Food From Soil Science” right now. It should be online in a few days. There is also a small collection of Tiedjens articles (and related items). If anyone has any other Tiedjens materials, please let me know. I have found Tiedjens mind-blowing.

Basically, what he did was to load the soil’s exchange capacity with calcium to 85% saturation and paid little attention to Mg other than to limit it to 10% of that 85%. In consequence, tiny quantities of liquid fertilizer did what it took regular farmers 10x the amount of ferts to accomplish. In case you don’t know, Tiedjens popularized (and did the fundamental research on) foliar feeding and hydroponics. He enjoyed taking worn out submarginal farms and converting them to highly productive land by the use of lime and almost homeopathic doses of fertilizers. Does anyone have any thoughts about the difference in outcome between targeting 85% calcium saturation (including some Mg) from the surface to four feet down, and paying no attention to the rest of the elements; or, targeting 68:12: 4: 2, as Albrecht advised.

Steve

 

 

Dear Steve,

Thanks for this. Seems like another proof that dynamics trumps substance in growing plants. I’m sure Tiejens is right in his results, and they should be easy enough to replicate.

Just off the top of my head I’d like to know the sand, clay and humus contents of the soils he experimented with.

However, with 85% Ca in his CEC he must have had a very porous soil even if it was heavy clay. That could mean good root penetration if the soil was mellow. On top of that, if he cut back the inputs of such salty things as NPK ferts tenfold (e.g. from  100 lbs/acre to 10 lbs/acre) they then wouldn’t burn off all those fine, penetrative roots like they normally do in commercial soils. That would allow the plant to have a large, fine root system with good symbiotic biology to glean the nutrients needed from the soil. Seems like a no-brainer, and should work with a range of light to heavy soils, though I suspect as a hydroponic researcher he was looking at the lighter end of the range. But maybe not. Personally I prefer to cut back even more on the inputs. I wouldn’t use any soluble nitrogen at all, but then it helps to use the BD preparations.

Starting a new garden on heavy, basalt clay in Guyra, NSW I’ve dug up the sod, separated the plant matter out for composting and planted English spinach and garlic together as companions in some parts. In other parts I’m growing a cover crop mixture of cereal rye/snow peas/mustards/turnips and rape, and along with them cabbages, broccoli, wong bok, kale, etc. On the surface I sprinkled a thin layer no more than 0.25 inches thick of fine, of mellow compost to make up for what I removed and to give a little humus to ensure the ‘earthly forces’, as Steiner describes them, work downward into the soil while the ‘earthly substance’ of lime works upwards.

I should add that this particular combination only works in autumn and winter. It’s autumn here so the light ether is receding though it is still working into the soil as the sugary products of photosynthesis being exuded at all the growing root tips, while the inner warmth of the earth rises up from within. There is a great dynamism occurring between what goes on above the soil surface and what goes on below.

I’ve been feeding the neighbour’s sheep with the rye and turnips because if I didn’t trim them they would be shading out the cabbages, wong boks, etc., and light is somewhat limited at this time of year. Theoretically the cover crop of rye/turnips/rape/mustards and peas are robbing the cabbages, broccolis, etc. of moisture and nutrients. If you pulled them all up and analysed them, they’ve taken up an enormous amount of water and nutrients from the soil where the cabbages are growing. That’s not what it looks like, though. It looks like they’ve nourished the cabbages.

I must confess that with a lifetime of experience I was watching for signs the cabbages, broccolis, etc. might be short on anything because I plan on eating them and this isn’t just a scientific experiment. I want better food than what’s available in the shops. I saw signs of zinc deficiency (clover leaves were very small in the paths, some cabbage leaves were deformed at their tips) and boron deficiency (wilting of broadleaves in mid-day heat, hollow stems in some mustards and peas) and gave the garden a light application of zinc sulphate along with a drench containing some humic acid and sea minerals (Olsson’s, rich in boron, etc.) but no nitrogen. There were also signs of copper deficiency (rust in the perennial rye pasture sod) but I figured the sea minerals would suffice for this. Of course, I’ve got the BD preps working, which in this case has been with a field broadcaster without any spray application in the traditional way. The growth is very robust and very lovely. Why would I spoil it with whacking doses of fertilisers when I can keep the biology going by growing companionable plants that complement each other and together keep the soil alive?

The common notion that we have to whack in a lot of NPK on things to equal what we might remove in crop material is a weird notion born out of failed observation. It simply isn’t true. We all should know that the most important of the NPK inputs—the N—is hovering in colossal abundance over every square centimetre of soil if we only provide a way for it to get in to where plant roots are giving off carbon compounds at their growing tips and microbes are converting the energy this supplies into nitrogen fixation, a very energy intensive process. Sure, we’ve got to have a lot of fine, growing root tips for that to happen. Why screw it up with massive doses of nitrogen salts? That would inhibit, if not burn, all those fine roots and shut down any microbial nitrogen fixation while leaching a wide range of nutrients starting with boron, silicon and calcium (I’m in a part of Australia with fairly reliable rain).

Hugh Lovel

 

 

Dear Hugh

Tiedjens put it this way: the TCEC of the soil is like deep shelves in a warehouse. Although a chemical extractant may get elements off the inner parts of the shelving, the plants may not. They do best getting what’s on the outer edges of the “shelves.” The soil test may show adequate amounts; the plants may not experience it that way. So if the exchange capacity is first preloaded with calcium, right to the brim, which is about 85% saturation, it leaves only a little space for other elements, and these will be readily available. So a small amount of NPK in liquid form will have a 10x effect compared to dumping it dry into “hungry” soil.

I had a major realization about this just recently. My own COF system is basically a Tiedjens system and I have not realized that for 20 years. I am having the user spread lime at about half to one ton/acre per year, year on year, gradually resulting in “overliming” that means less and less seedmeal and etc is needed to get a growth response, so as the soil is ever more fully loaded with calcium and more deeply loaded (down to 4′), then it needs less and less ferts, so the COF user gives less calcium as well. When I got worried last year about overliming my garden with COF, I was worrying about nothing. I’m definitely going to set up an area in my garden to run on COF. And if Tiedjens is right, then I can put small, safe quantities of Zn, Cu, Mn and Fe and B into the COF and they’ll be 10x as effective in tiny quantities. In ordinary soil it might take 250 lb K to make a big growth response but in calcium-saturated soil it might take only 50 lb to do the same thing.

Thinking this way, it would be good advice to someone starting a new garden where no significant soil improvement has yet happened, for starters, to spread ag lime at one to three tons per acre (depending on soil type). After that, COF will continue to build calcium levels. And I think having some gypsum in the COF will get calcium into the subsoil a lot faster than Tiedjens thought possible.

Steve

 

 

Dear Steve,

You may be on to something, but I wouldn’t be too simplistic about this.

What Tiedjens is pointing out is the TCEC (Total Cation Exchange Capacity) is an ion exchange medium with storage of Ca, Mg, K, Na and H along with a few traces such as Fe, Mn, Zn, Cu, Co, Mo, etc. If the exchange medium is full, adding more calcium as calcium sulphate will effect some exchange between the excess calcium and some of the other cations and flush them off the medium. But adding lime will displace H. So as long as there is some Hydrogen in the exchange medium adding lime will mostly just displace hydrogen.

With clay as the ion exchange medium, the ions are layered. In a clay such as calcium bentonite there can be many layers of cations and even more layers of water attached to each clay particle. The colloidal particle size of a clay is down around ten to the minus ninth centimetres (1/1000000000cm), and at that size there are still a vast number of aluminium silicate molecules in the particle—which means there are a lot of layers of other positively charged atoms or molecules attracted to the anionic clay particle to balance its negative charge. Since the bonds are ionic rather than covalent (as with carbon chemistry) they constantly shift. However, the most tightly bound innermost layers hardly shift at all, and as such may not be exchangeable—which is why an aqua regia digest can show such markedly different results from a Mehlich III analysis. In plant tissues even the strong bonds, such as the magnesium held in the centre of a chlorophyll molecule, are important—so we use the aqua regia digest for tissue tests. But for soils this generally isn’t done because those innermost elements are generally unimportant and Cation Exchange Capacity does not take them into account as they aren’t generally displaceable. Anyway aqua regia digests show these innermost layers generally are populated with iron and magnesium rather than calcium.

We can’t just add calcium as lime to a low calcium soil and pump its ratio of cations up to 85% without—in many cases—going overboard into high pH. If we did we would have to nurse a steady stream of micronutrients through the medium to replace the elements calcium shunts off the medium to leach. The stream may be slight, but, depending on the availability of water and tendency to leach we are setting up conditions that render trace elements unavailable. You can add lime until you get the pH pretty close to neutral, but going overboard is not helpful. So you can add gypsum (calcium sulphate) and have some effect, but that also has its limits and until the sulphate leaches you may have an excess and THAT will readily leach copper, manganese, zinc and cobalt, which could be frustrating.

If you get too high a pH roots will pick up so much silicates along with the hydroxyl ions that it shifts the balance between silicate and borate and the roots swell but fail to transport fluid. To get the fluid moving again and reduce root swelling you have to add more borate—just the opposite of what you’d have to do in case you erred on the side of too much borate, had too much sap pressure and had to add silicates to achieve balance.

So mind the balance between the H ions and the OH ions. That’s your pH. With your high CEC soil you might add lime and have a wonderful experience, but that same recommendation to someone on a light soil might be ruinous.

With your COF (Complete Organic Fertiliser, I assume) approach you’re not doing quite the same with minerals, seed meals and so forth as a hydroponic grower would do with his totally soluble nutrient approach. The ‘organic’ hydroponic grower may complex his cations, including his traces, with humic and fulvic acids, and he may add micros very subtly with soluble kelp extracts and so forth but with hydroponics what you put in is all soluble. Thus you put in a trickle rather than a gush, like a Tiedjens system, and in most cases you wouldn’t put in enough at any one time to do root damage. Maybe with nitrogen inputs nitrogen fixation and amino acid release will be impaired or shut down, although I have seen hydroponic run-to-waste systems in heavy clay/loams where bacterial nitrogen fixation and protozoal amino acid release was working well enough to yield quality results.

Your COF approach with minerals and seed meals, etc. is much more of a trickle in system that works over days and weeks rather than directly via solubility. It feeds a wide range of soil organisms which digest and work it into the soil. Because of the activity it evokes it gives over a very fine stream of nutrients to the clay. It’s slow release and as such is already in the range of scaling back to a tenth of the input levels of soluble fertilisers such as the NPK type. If it was too much all at once the clay might not handle it all.

But I like your idea of some lime to draw this fine trickle from your COF upward into the plant. What I would suggest you try is a very dilute watering solution of hydrated lime [Ca(OH)2] and water that into the soil along with applications of the COF. Alternatively you might mix something like 0.1% hydrated lime into your COF formula—not enough to shift soil pH much even on a light soil, but enough to affect the activity of nutrient uptake without the danger of what Michael Astera was talking about where high pH results in fluid retention and root swelling. Otherwise, check your soil pH and add lime as you would normally. With a heavy clay like you’ve got, you could probably use some lime just to fill up your soil storage bank a bit.

And I might also suggest you will get a steadier trickle from your COF by placing it at the surface or just slightly below where the soil biology works it in gradually, rather than mixing it in deep so it works in too quickly. That’s where I believe you will get those good results Tiedjens was talking about.

 

Best,

Hugh Lovel

 

 

Dylan Ford, Long Island, New York responds:

Steve S, Hugh, et al

I’ve read probably as much received nonsense regarding growing crops as anyone, and one statement I encountered many times in the past has always troubled me.

“Lime makes the father rich, and the sons poor.”

Anyone got a clue as to what this might portend? I am particularly confused in the reference to the Calcium saturation prescribed by of Tiedjens and Solomon.

Dylan

 

Dear Dylan,

Very interesting.  Honestly I think this is one of those wry folk sayings that came from observation but isn’t always right. We have to keep coming back to observation and keep making observations rather than rushing to conclusions. No doubt this saying came from multiple observations, but I think it left out a few.

I think we’ve all seen instances where a deficiency of lime can be truly impoverishing, even though over liming, which I think Steve should be careful of, can indeed be detrimental. Over liming, and even over application of gypsum or dolomite, can unbalance the soil and may drive important trace elements off the clay colloid. In the case of gypsum the sulphate can leach copper and other trace elements and most soils don’t need that at all.

Liming shouldn’t be used simply to raise the pH. Dolomite raises pH more and often is cheaper, but too much dolomite can lock up a heavy soil so it doesn’t breathe well enough. It shifts the ratio of calcium to magnesium over to the magnesium side. Along with iron, magnesium tends to migrate into the inner layers surrounding the clay particles and makes the soil sticky when wet, and most heavy soils do not need much of that. It also can be expensive to correct.

Yet, bad lime advice abounds, and liming frequently is used just to raise pH. That can be a serious mistake and is just the sort of thing that makes the father rich but the sons poor. For more than a hundred years liming to raise the pH has been the norm taught in most agricultural schools, and the results have been masked by ever increasing applications of NPK—just what many ag schools are selling. People who make up sayings like this would be sure to notice, while ag professors might ignore results that didn’t fit their theories.

So there’s a lot of truth to the adage, “Lime makes the fathers rich but the sons poor”, but it isn’t universally true.

Best wishes,

Hugh Lovel