I have found that adding acidic matter does work. Besides peat pine bark is acidic too. You need small pieces though. I also only use rainwater which is 5.0 to 5.5 here in my area. The only issue I had was once I got the mix too low. I added too much sulfur. PH got down to 3.0. I had to flush beds with tap water ( 8.0 here). I lost a plant too. Most survived. I have ten blueberry plants.
My native soil is clay loam and most plants love it. I recycle potting soil into raised beds. I grow a lot in containers too. Why this subject caught my interest. You canāt do much to change native soils but you can control everything in containers.
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I donāt know. Or at least I donāt yet know.
Having organic matter in the soil is important, for sure. It is a good way to improve several soil characteristics, and you need it for soil microbial activity. But I think, outside of a few very unique climates, there can be too much of a good thing when it comes to organic matter. And even in those climates, they can have pretty serious problems given unfavorable weather conditions (crops drowning in fields, tractors getting stuck, etc).
So, I am not convinced just having 15-20% organic matter is the right way to create a superlative soil, even though it is clearly good to have something like, to spit out a rough number, 5% organic matter.
But, while that is probably enough to have good pH buffering and microbial activity, itās hardly enough organic matter to have the really high CEC and water holding capacity that Iād want to see, let alone aeration. Maybe paired with a younger clay soil, but then youād have issues with drainage and aeration, which is arguably worse.
To my mind, then, you want some kind of mineral component of the soil that contributes substantial CEC, aeration, and both high drainage and high water holding capacity. Physically, that is actually pretty straightforward: you need fairly large mineral particles for the drainage, and very high porosity for the CEC, aeration, and water holding.
Which then points us back to volcanic soils. Volcanic soils are fairly coarse and typically very high in amorphous glasses and weird semi-mineral colloids that are highly porous and many of which, such as imogolite and ferrihydrite, combine high chemical activity with extremely high surface area. But few of us have active volcanos in our backyards, so getting our hands on agriculturally significant quantities of those kinds of things can be somewhat challenging.
There are a few methods, albeit under-explored and under-researched, that approximate these soil characteristics. If adding dump-truck loads of compost is a way of trying to replicate chernozem (which, I would argue it is), then adding perlite, expanded slate, charcoal, and baked clay are all ways of trying to replicate volcanic soils, to varying degrees of success.
Perlite is the most direct comparison, because perlite is volcanic glass. When you add perlite to your potting soil, you are adding volcanic glass. That pot of compost, duff, and perlite you keep regularly watered and bring in for the winter: Itās your unconscious approximation of Hawaiian soil, and your potted tropical plants and citrus love it for the exact same reasons they love growing in Hawaiian soil. But, well, perlite has serious limits. Itās expensive, thereās only so much of it, and chemically it is pretty meh, being mostly just silicone dioxide, so any CEC improvements it provides are mostly just due to it having great surface area.
Expanded slate, aka permatill, is similar. Chemically, it is not much to write home about, achieving the effects it does by brute force of surface area. But, provided you live within about 50-100 miles of Salisbury North Carolina, it is an order of magnitude cheaper than perlite. And, being not quite so light, can actually be applied to garden soil and wonāt just wash away. Really large particle size also means that permatill is incredibly fast-draining. My understanding is that it also holds on to air better than perlite, which makes a big difference once weāre talking about improving the soil beyond the first few inches (which is another thing this thread hasnāt really dealt with: the depth of biologically, hydrologically, and chemically active soil is incredibly important).
Charcoal has been mentioned, if obliquely, already, in @Noddykitty 's post about terra pretta. Looks like this one is at least getting some research, though my feeling is most of the research is not likely to be all that applicable (too little is applied, itās too fresh, and they donāt really seem to be designing their experiments to test what itās actually good for half the time). Charcoal, properly made, is fairly chemically active and has great porosity. So, in theory, once it is conditioned a bit, it ought to be an amazing soil amendment. But I am not sure it is economically feasible to use it in the quantities I would expect youād need, barring a serious breakthrough in energy prices (not likely, given the technological and political hurdles).
Baked clay, aka brick dust or broken pottery, is another one that comes up once discussion of terra preta comes up, and also seems to have been important in a lot of historical urban gardens. Overall, Iād say this is most similar to charcoal, but with the addition of being more energy intensive (bad), slightly heavier (probably good), and somewhat more durable (good).
So, there is the traditional route: approximating chernozem, and the alternative route: approximating volcanic soil. Perhaps loess soil is some third way, but thatās one where Iām not aware of any soil amendments that make your soil more like loess. Again, I donāt think in most cases people are consciously trying to make their soil like some other soil, but in effect that is what they are doing, and their motivation for doing so does basically boil down to trying to emulate some kind of famous, highly fertile, natural soil. Moreover, putting amending soil into this kind of framework goes a long way towards establishing goalposts and yardsticks; it clarifies what you are doing, why you are doing it, and what your end goal is. They say gardening is about building soil, not growing plants, so I say, might as well know what kind of soil it is youāre trying to build.
Welp, those are my thoughts so far.
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I agree with people said that there is no ideal soil. Different plants require different conditions to grow , not just soil alone. My soil is very clay,about an foot or so top soil then all clay underneath. Once i choosed the house, I canāt choose the soil. But i understand in general that more organic matter in the soil is better for plants. So I bury kitchen waste, paper shred, anything that can be turned into organic matter. Hopefully, over the time, my soil will be improved a little.
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I live about a mile from the Mississippi River and the soils here are mostly sand. The soil is great for oak, maple, pines and good for all types of weeds but for veggie gardens iāve added a lot of woodchips and I fertilize often in the growing season. Another thing is the soils here warm fast in the spring which helps in this climate. Not perfect, but you can make it work.
For me the only ideal soil for farming is one that gets nothing added to it by the gardener and yet plants grow and produce healthy tasty food. No extra water, nutrients, PH adjustment etc. Are any of us on this forum growing plants without additives using ideal soil?
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Hey Iām in California, no water? I can grow cactus but I donāt like to eat them all the time.
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The loess soils are mostly Illinois and Iowa. Maybe the Mississippi flood plain was too narrow near you to get much wind action. Or maybe glaciers did something to the area. Or maybe your soils are more recent flood sorted material, not wind deposited. Sandy material sounds like water sorted parent material. Sandy soils can be good soils. For fruit trees Iād rather have sand than clay, by far rather.
Wisconsin soils are mostly glacial till, material dumped out of melting glaciers.
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This area wasnāt glaciated, hence this area of the country is called the Driftless Area.
Driftless Area - Wikipedia
Found this from a book from 1914ā¦ They didnāt have much good to say about the local soils.
Taken as a whole Plainfield sand is considered a poor soil. A large part of the type is
under cultivation, but the farm buildings and improvements are
poor and indicate a condition far from prosperous, while many
houses are vacant. . Some truck crops are grown near La Crosse,
but owing to its coarse texture and loose, open structure, the soil
is so droughty that yields are unsatisfactory. Even during favorable -years corn seldom yields over 20 bushels and rye over 15
bushels per acre.
You can google your local area+soil and find a lot of maps/info on types/etc.
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Thatās a geologically complicated area. I havenāt had the chance to spend much time there. But wish that I had. I got involved in agriculture and spent most of my time in the flatter farm country.
Definitely one of my favorite areas in WI. Vilas/Oneida/Price/Forest counties is #1, the Driftless Region #2
I spent a fair amount of time looking at land around the Prairie du Chien area a number of years ago before re-locating here. It wouldnāt take much to get me to move there now.
I havenāt spent much time on this side of the river looking at the Driftless Region of MN, but my understanding is that it too is pretty cool.
Adding to the Terra Preta argument, these folks tried several recipes before settling on the one that gave them the best results (their recommended clay component was turface).
http://honeybees-by-the-sea.com/terrapreta.htm
They even have a PowerPoint, which Iāve converted to Pdf (my preferred storage format):
Terra Preta Nova.pdf (8.2 MB)
Then thereās the Back to Eden method, which seems to place emphasis on heavy use of wood chips.
Iād like to try both combined, while spawning the wood chips with mushrooms. And heavy use of zoocompost (redworms, Black Soldier Flies, roaches, millipedes, isopods, etc.), as well as manure from any herbivorous pets I might keep (goats, guinea pigs, etc.).
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silt! my little area is just plain silt. Iāve added a lot to the soil and two big pine trees drop a lot too, but under that is compacted silt.
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The issue I have with most terra preta enthusiasm is similar to the issues with more legacy (just add more compost!) methods: thereās not not much in the way of rigorous study or detailed understanding, and people are generally satisfied just seeing some improvement and will call their method a panacea on the slightest benefit.
For example, the links you provided contained the exact same information Iāve seen in rando blogs, MotherEartNews, etc. Heck, the NCSU guy didnāt even have a control plot (really, he should have had several, since he was adding multiple different amendments). And he planted his experiment with just some standard cool-season vegetables. If you actually wanted to investigate this stuff, youād plant sweet potatoes, citrus, and cacti together with bigleaf hydrangea, mallows, and white clover to test the internal drainage vs water holding capacity, youād dig a 6+ ft deep bed of the stuff and plant big bluestem, sweet clover, and mesquite to test root penetration and deep soil aeration, youād plant a similar bed with Luma apiculata and other Chilean species with extremely high root respiration, then periodically flood the soil for short durations to see if the tightly air pockets would keep the roots oxygenated long enough to prevent suffocation (a common issue with growing otherwise well-adapted species from Chile and similar climates), youād plant a well-rested bed of the stuff with banksia and other protea and Australian acacias and test different phosphorous fertilization regimes to see if the higher chemical binding would slow or reduce phosphorous toxicity in those species, heck, if you wanted to have some real fun, youād get ahold of phytophthora susceptible species like Wollema nobilis, Agathis, or susceptible west coast conifers and see if the superior drainage would help with the water mold issue, etc. Donāt just plant some lettuce in fresh āterra preta novaā and call it a day.
I have seen some decent research on feedstock material and production method, so thatās good at least. Seems when high-nutrient material, like manure, is used, P and K is mostly retained, but at best only 50% of N is, less at higher temperatures. And those higher temperatures are better for the actual formation of highly porous and durable charcoal. That much is good to know.
Going beyond that, it is not clear whether the benefit is more derived from the pottery shards or the charcoal. Most studies, and certainly all the hype, is focused on the charcoal, but in Amazonian terra pretta de Indio, pottery shards contribute up to 30% of the soil volume. So, is it the charcoal, or the pottery thatās doing the legwork? And, while pottery shards are clearly useful, they still donāt have the porosity of the true volcanic stuff, and likely donāt have the durability.
If pottery, thatās quite unfortunate. Charcoal you can conceivably create in large enough quantities, and it has the side benefit of fixing carbon. Pottery, however, requires far, far more energy, and the feedstock would have to be excavated or mined, you couldnāt just use waste or on-site materials. Now, if there were a major breakthrough in energy production, sure, but again, technologically and politically, weāre far more likely to see energy prices increase by an order of magnitude rather than decrease. But, dude, if energy was 10 or 100 times cheaper, this would be a solved problem. Heck, with true energy abundance, all of agriculture would basically be a solved problem. You could churn out all the charcoal you want, and, forget pottery shards, you could use higher heat and pressures to turn dirt into scoria (heavier-than-water pumice) and pulverize itāliteral volcanic soil wherever you want it. You could afford to distill and pipe all the water youād ever want, to turn all of Arizona and Nevada, northern Mexico, interior Spain, northern Argentina, all of Australia, etc, into bigger versions of the agricultural paradise that is the (irrigated but otherwise semi-arid) central valley of California, and those former semi-arid subtropical plains and deserts would produce so much high-quality food that agriculture in traditional agricultural lands, which is where most people live, would be vastly reduced, returning it to nature. Every major city could easily surround itself with thousands of acres of parks, game lands, and wildlife preserves.
But, anyway, utopic fantasies aside, we donāt have that kind of energy abundance, and might end up with the opposite, with all the environmental and social costs that entails. So, even large scale production of charcoal, if it does actually prove to be as good a soil amendment that it promises, is likely going to be out of reach.
Whatās a fella to doā¦ They wonāt let me build my own nuke-powered biochar and pumice factory, but they wonāt build one for me either. Itās like trying to sell home cured meat and raw dairy all over again.
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For consideration, Iād like to submit one more link:
The guy over-saturates his farm with compost (his soil is over 4 feet deep) and heās beating the drought and actively producing while the surrounding farms are struggling.
Nothing systematic though, so there may not be much to enlighten us about soil fertility.
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That article has to be one of the worst Iāve ever read. You could have said the same thing with 1% as many words. The only number I got out of it was this farmer is applying 60 tons per acre per year of compost. Everything else was hyperbole.
Thanks for the article!
Thereās a lot here worth touching on. Though fruitnut is right, itās a chore to read through the bloat. Thereās a few things that I liked with his system, but overall I have more criticism than praise. His overall goal, though, I fully commend.
Iāll try to write up my full thoughts over the weekend, but in short:
Way too much compost. He got lucky that it didnāt backfire, and that it is even feasible.
Not a fan of municipal waste going directly on vegetable crops.
Bleh, the āI saw one time how having ānatures balanceā reduced pest pressure so it must be true in all casesā rears its silly head . n=1 does not a strong case make.
Municipal waste isnāt the solution, though I am in favor of its being used and not wasted.
āHis land was low, cold, and wet.ā And then āHe withstood the drought better than other farmers.ā Ya donāt say 
His compost addiction, which Iād call a chernozem fetish, really underscores the need for some kind of more persistent mineral amendment that performs similarly to compost.
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He hasnāt discover anything new. Even during a drought if I dig under the 4 inches of green mulch around my trees the soil is still moist there.
Early this year I was showing my daughter how powerful proper techniques were. I planted some hops straddling a soft fence and only got around mulching one side. The bare side was already hydrophobic and I could not even irrigate it without the water just running off, the mulched side took a whole lot of water before it became saturated enough for it to run off. The soil I prepare is highly organic (at least 50% well cured horse manure) with year after year of decomposing green mulch; the setup can both soak up water and keep it.
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That area is well known for growing roses, I donāt think it has bad soil. I recall visiting the Antique rose garden there years ago.
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Wow, tough crowd. I canāt speak to the merits of the information as Iām one of the more inexperienced members. I knew nothing written there was new, but nonetheless I had hoped the information was collected concisely enough to be of use. Iām probably biased though, ācause I do enjoy a good narrative writing style (Luther Burbankās 12 volume work is enthralling, to my tastes).
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Sorry, it wasnāt you it was me and sometimes my age shows. I prefer numbers, something to back up the narrative. The author must have gotten paid by the word.
@a_Vivaldi will have something more informative to say about the topic. Heās a lot smarter than me.
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