Soil Fertility: How to achieve; more discussion on Boron and other minerals; Biodynamic application


Re: boron application w/ prep. 500 or 501/Too much boron?


Dear Michael,

I need to thank you for correcting my mistake in treating borax the same as solubor. That was a mistake and I acknowledge it.


I like your idea of lacing the horn preparations—particularly horn clay if you make that—with a trace of boron. I like to dilute to 3x or one part in a thousand and adding modest amounts depending on how many horns I’m burying.


I also acknowledge your pioneering stature in popularizing the re-mineralization of soils, but even though you may be a leader it is a bit puzzling that you seem to think you are out front of the entire pack. My first acquaintance with cutting edge soil science was in 1976 with Carey Reams, who lived about 30 miles away from me in Georgia. Surely you’ve heard of him. Arden Anderson, Dan Skow, Phil Wheeler and Bob Pike, to name a few, were all Reams students. But the first soil remediation formulas I was satisfied with that addressed optimizing sulphur, boron, copper, zinc, manganese, moly, cobalt, etc. were in the eighties with Agronics, Inc. out of Albuquerque, NM. They were using A & L Labs out of Lubbock, TX and mixing major and minor nutrients into leonardite mined in Cuba, NM. I visited their mining and blending operations. They sold these fertiliser mixes to farmers by tractor trailer loads, each load tailored to specific needs as identified by soil testing. I had, of course, encountered Neal Kinsey’s approach, and he was targeting boron and all the traces as well, but he wasn’t feeding the soil’s biology the way Agronics was and his approach didn’t make as much sense to me—though I’ve seen it get impressive results in state of the art trials covering 100,000 acres of citrus in Florida. But despite Kinsey’s track record, I had taken soil microbiology as part of my biochemistry curriculum, so I couldn’t think of the soil simply in terms of minerals when I knew how important the biology was. By the ‘90s I had learned to make good compost and add deficient minerals after many experiments making poor compost, bad compost and some reasonably good composts, and I was always chasing that biodynamic ideal of self-sufficiency in fertility. I wasn’t inclined to fool myself with mediocre results. I used boron (as borax at 5lbs/acre for a single application) and other trace mineral supplements from my second year onward as I started farming on a very impoverished soil. Over the past 37 years I’ve seen a variety of approaches, and here in Australia the approach Graeme Sait (Nutri-Tech) uses has been my standard. Graeme has been an early adopter of a wide variety of things, and one of them was my advice in 2000 of making silicon standard on all his soil tests. It was Graeme who taught me that humic acid was great for delivering boron to the soil foodweb and ensuring its uptake by plants. He promotes the use of a product that is granular humates (85% soluble) to which 10% boric acid has been incorporated. At 25 kg/ha this delivers a 0.2 ppm adjustment to boron levels in the soil, and I’ve seen many examples where zucchinis cucumbers, soybeans, etc. can be damaged in their initial sprouting stage at higher rates than this. But 0.2 ppm isn’t much of a correction for a soil that has only 0.3 ppm (or less) boron to begin with. It would be okay for grassy species like perennial ryegrass, sorghum or sugar cane but it won’t cut it with clover, brassicas, cucurbits or beans. For broadleaf species, and especially legumes, 1 ppm is the lower limit of adequacy. So for those crops, which would be damaged as seedlings by a 0.2 ppm adjustment delivered via humic acids, have to be side dressed by an additional application or two prior to flowering—once their transport system is big enough to take the additional sap pressure. So horticultural growers can put it on via fertigation, and broadacre or pasture growers may have to boom spray or fly it on, but the results can be impressive. And they will be just as impressive in a small garden if applied at this rate with a 0.2 ppm adjustment each time.


Perhaps It needs emphasis that in agriculture if a little bit is good, a little less more frequently is better. I also favour the belief that every soil is different—I see it every day.


I don’t know where you get the idea that most of my work is with radionics, but I find radionics is pretty hit and miss when soil biology and trace elements are weak. Radionics works with life, and if what you’re working with is barely alive radionics isn’t going to work very well—or at least nowhere near as well as when one gets the minerals and biology right. I just came back from a tour of dairy farms in western Victoria and South Australia—two dairy farms per day for 10 days. These were herds of anywhere between 300 and 700 milkers and the best one—who had been on the biological path for 4 years—was about 40% of the way to top results. He had pH 5.7, 10% organic matter with a Total Exchange Capacity of 44.21, and was massively calcium deficient at 4741 ppm Ca (Mehlich III) when his target was 6190 ppm. I use the rule of thumb that 250 kg/ha delivers the per cent analysis in ppm to the field, so at 35% Ca lime he would need over 10 metric tonnes of lime. Actually his total test showed 5734 Ca so some of it was not releasing and probably was held as a chelate in the humic fraction of the soil. But 10 tonnes is out of the question anyway. I never recommend over 4 T/Ha in one dose. He was also in excess for both magnesium and sodium, but the real story was his deficiencies in sulphur, phosphorous, manganese, copper and zinc. According to the Mehlich III test, which you prefer and I do too, potassium was deficient, but he had a huge reserve in his totals—far and away more than needed, and I’ve found that when phosphorous is working at luxury levels the soil microbes release potassium quite nicely from reserves.


We walked everywhere and dug up sod in several places. I showed him the visual signs of zinc, copper, manganese, sulphur and phosphorous deficiencies, while his silicon levels were unusually good at 76 ppm and boron was at 3 ppm. My target for luxury silicon is 100 ppm and boron at 3 ppm, but 76 ppm was good enough with 3 ppm boron that all the regrowth around the most recent cow pies (grazed 15 days prior) was erect instead of lodged and matted. That made him the best of the 20 farms as all the others showed signs of silicon deficiency in rampant and matted grass around manure patches. To put this into perspective, the others were only 30% or 25% or even less in turning around their pastures. Even so there were places where his clover leaves were the size of lentils instead of silver dollars (zinc deficiency), places where his ryegrass was rusty (copper deficiency) places where leaf mottling suggested manganese deficiency and so forth. One thing he did not show at 3 ppm boron was boron deficiency. All his clovers were solid stem—which is just about never seen where inputs such as urea are used. It’s not so easy to tell with grasses, but his dandelions, chicories, plantains, etc. showed no signs of boron deficiency.


According to your rule he should have had somewhere around 5 ppm B—so I disagree with your rule. I have seen 5 ppm B in bananas, and they set an extra 3 hands of bananas per bell with larger bananas. But bananas are an extremely large, siliceous plant that can use a lot of sap pressure. But if I was planting suckers in a new paddock I’m pretty sure 5 ppm B would be excessive as I’ve burned new plantings before with using an excess of boron humates—not seriously. They lived and grew out of it, but I should have been more careful. We can always add a bit more, but too much is hard to remedy.


I had others with heavier soils with more boron (e.g. pH 6.2, 9% organic matter, TEC 56, 4873 ppm Ca, 4 ppm B), but I’d say the soil cited above was fairly representative of the dairy soils in this group of about 45 tests. I don’t mean to imply that these dairy soils are anything like broadacre or horticultural soils though. Dairy pastures build high organic matter and potentially rich soils. I’ve seen as high as 22% organic matter. Ordinarily boron leaches along with nitrates, and this usually means that their effluent ponds are rich in both nitrates and boron. So when they are recycling their effluent on their paddocks they tend to build luxury levels of boron, which are almost never seen elsewhere unless the soil is a collection point for minerals leaching from other places. However, I had one organic fruit grower who was putting boron on routinely and it was leaching along with nitrates (because he was an organic NPK farmer who used poorly composted raw manure) and it went down about 2 feet to where he had a heavy clay layer and built up there. All his older trees were getting their roots stuck into it and overdosing on boron. Too much sap pressure and the bark split and the trees died.


Please feel free to ignore my advice if you think I’m just a dabbler in soils that would prefer to fix everything with biodynamic preparations and radionics. You can also ignore my research into the biochemical activity of boron in the xylem cells of plants. I don’t know where you got the idea that I’m so full of baloney, but if it suits you, go for it.


My advice isn’t just for you, though. I gave it because I thought you might be oversimplifying things and being incautious in your use of boron. Like Jerry Brunetti I don’t take others’ target levels as gospel. I set my own when I see in the plants the signs of less than optimal performance. There are always deficiency signs for silicon, calcium, manganese, copper, etc. and that includes boron. I’ve seen a lot of people who think 1 ppm B is enough for any soil, but I’d be one of the first to agree with you that more is often needed. The Incitec/Pivot soil tests here in Australia say that 0.2 to 0.4 ppm B is sufficient, but I’m sure you’re right in setting the bar higher; and in high pH soils (above 7.0) a little extra boron is strongly advisable. The same goes for high moly soils, they require a fair bit of extra copper, and instead of 5 ppm Cu, which I like for good grass and clovers, I like to see 7 ppm or even 9 ppm or more copper depending on how excessive the Mo is. These things are all variable and their interactions have to be considered. Some of us cannot afford to be incautious. I doubt if any home gardeners are going to sue you for giving them bad advice, but that isn’t the case when you are working with 1000 hectare (2500 acre) farms. Incitec/Pivot made a very costly mistake that was in the news a few years back. It seems a yard foreman told a somewhat green worker to put a bucket full of molybdenum in a fertiliser blend, and the worker thought that meant a front end loader bucket instead of a 20 litre bucket. It got blended and went out on a big farm and the result was a multi-million dollar lawsuit. Incitec is a big company so they swallowed the loss, but it goes to show you. When I recommend a siliceous rock dust, for example basalt or granite, I get the quarry tested first. One basalt had over 8% P, which was a bit of a surprise. But it also had about 7% manganese and more than 5 T/Ha would be enough to seriously depress Iron on a light soil and make it marginally available—not something I’d want to be careless about.

Best wishes,

Hugh Lovel