TX, thanks, those look super-informative. I started the introduction on the first piece. It will take some time to get through it all.

I certainly agree it is a very complex subject. Chances are good that I have numerous misunderstandings about it all at present. What jumps out at me right away from the intro to the first piece is the statement that there is no justification for the common belief that if a plant seems to grow well and bears well that it will automatically be high in nutrition. This belief is as common among intensive and organic gardeners as it is among conventional farmers. Indeed I found it a shock only a few years ago to consider the possibility that my great-looking thriving plants might not be as good for me as I had imagined.

The electronic versions (pdf files) of the entire three volume set of Fertilizing Crops to Improve Human Health: a Scientific Review can be obtained (free) from the IFA website linked below. The link is to the page for Volume I - the other two volumes can be accessed via the links near the bottom under "See Also".

Here is a link that might be useful: Fertilizing Crops to Improve Human Health: a Scientific Review

Apparently the GardenWeb forums system is having trouble with html coding of hyperlinks within the message field when posting (e.g., the link to The Effect of Soils and Fertilizers on Human and Animal Nutrition in the original post). resulting in link failure at some time after the post. I've been conversing with their webmaster folks on the issue since yesterday, and what's happening isn't yet clear. The Optional Link feature appears to be unaffected, so I will repost the link to that work below.

Note - be patient on the download, the UC Davis server from which this comes isn't real fast.

Here is a link that might be useful: The Effect of Soils and Fertilizers on Human and Animal Nutrition

This post was edited by TXEB on Fri, May 3, 13 at 9:05

@ pnbrownï¼ I don't really think that big scale commercial crops could ever compare to your homegrown crops. Ever. If you think what you'd grown is not the best thing for your health than I don't know how commercial growers will do better than you seeing that they need to prioritize many other things more important than the crops nutrition value.

I didn't get that out of pn's post. He only seemed to be saying that a healthy looking plant - presumably, any variety, in any setting - is not necessarily an indicator of nutrition.

There are a lot of variables in this topic, including what variety you are growing and whether it has been optimized for other characteristics such as yield. If I interpret TX's post correctly, he's only addressing the soil and fertilization topic.

tox,

the other topics are also addressed in the works form IFA/IPNI. Of interest to some is actually using genetics and genetic modification to design plants that deliver increased nutritional components, especially micronutrients. I put up the references simply because the issue of directly improving nutrition via soil amendment has come up several times. It is a very complex issue, with many variables, and they aren't always what they appear to be.

TXEB,, The subject of introducing enhanced nutrients through GM can be a touchy subject for some gardeners. Usually in the past when food processors labeled their food as vitamin, or whatever, enriched, too often it has been a dusting uf inferror forms that are not well absorbed.

The whole field of GMing (perhaps a new word?] seems to be a field of great possibilities and horrendous possibilities.

TXEB, do you have a connection with the chemical industry? I'm sure you'll correct me if I'm wrong but since the one link I looked at mentioned the global fertilizer industry I'm guessing this is not about organic growing methods. I'm sure the global fertilizer industry would love to convince everyone who grows food that it's necessary to add their products. Would greatly add to their bottom line even if such additions to a home garden are totally unnecessary and possibly even unhealthy.

In order to have nutrient rich home grown food it's probably best for home gardeners to try to bring in raw compost materials from various sources and use organic amendments to supplement. There are many other things gardeners can do such as bokashi, biochar, and hugelkultur that will enrich the soil even better than synthetic chemical fertilizers. Even tho I don't grow a lot of food in my garden I like using alfalfa pellets for fertilizing as it's a heavy feeder with long roots that bring nutrients from deeper in the soil than most plants.

IMO a varied diet for both one's compost and one's body is the best way for both to be healthy. For many people it might be wise to take a multivitamin or mineral supplement which I do, but stressing about how one's homegrown vegetables can be made even healthier is not something I want to do. And purchasing synthetic chemicals made by the petrochemical industry is not something I'll ever do for my garden and especially for my health.

luckygal - a fair question.

I am a retired chemist, been retired for 5 years. Before that I had 25 years in industry, but not fertilizer. I have no interest in promoting the industry, and have not done so.

I posted these as references that offer some of the best, credible research results on the problems facing a world with growing nutrient shortages. It is a topic that has come up in several recent threads on soils, their impact on plant nutrition, and in turn, the impact on human nutrition. That is really the focus of both publications. I did not see them as promoting the use of any particular kind of fertilizer.

The first reference was from the USDA - no industry interest - in 1975. The second was, in part, sponsored by an industry trade group.

If you read through both references what you will note is that organic matter is identified repeatedly as a key component of soil for agricultural production. They also identify the critical nutrients needed, both major, micro, and trace element. How you get them is up to you.

The issue has become one of global importance, and is viewed as critical by the UN. Nutrient deficiency is at epidemic proportions in developing and underdeveloped countries around the world. The real issue is how to resolve it. I can appreciate the IFA's interest in that regard. I highly recommend reading the Introduction / Executive Summary in the second reference to put things into perspective.

BTW, I mostly agree with your views on how to best get things done. But, that wasn't the point of my post. I guess you missed that.

"The subject of introducing enhanced nutrients through GM can be a touchy subject for some gardeners."

The major players in the GMO industry isn't interested in enhanced nutrients through GM except for tapping agriculture availability deficient areas where a single staple crop feeds a majority of the people, such as "golden rice" availability (Vitamin A enhanced). Even then, it's a rather minor interest mostly pushed by non-profits and educational institutions. The real money is where people who can afford expensive seed are putting the stuff in the ground by the 100-1000s of acres.

In industrialized and richer nations hardly anyone cares even the slightest bit about nutrient content. A tomato is a tomato and very few people are going to pay a few cents more to get 10-25% more of whatever nutrient enhancement is taking place. Heck, even if "golden rice" was traditionally bred and hit the market with no objections (which for some reason people don't care about it crossing with traditional crops as long as it isn't GMO, even though implications on genetic crop pollution would be the same), it probably wouldn't have a market in most industrialized nations.

For most manufacturers of GMO the focus is herbicide tolerance, pesticide introduction/tolerance, drought tolerance, Al toxicity tolerance, disease tolerance, and industrial trait production (such as BASF's now abandoned potato starch project for the paper industry).

Producing a GMO crop is an extremely time, labor, and land use extensive. 99+% of everything put into a GMO test field is discarded because of a lack of "takes" or undesired accessory traits after a desired cross that "took".

The "big six" of GMO are interested in the farmers that grow 100s-1000s of acres. While some people think the world revolves around Monsanto (which is a relatively minor player at this point, except in patent holdings and some international exclusive markets) the major players in the non-grain/cotton markets are the small-business GMO setups tapping markets that the big boys won't touch...especially in the tree fruit industry.

This post was edited by nc-crn on Fri, May 3, 13 at 17:53

Keeping one of these threads on track is like herding cats. ;-)

GMO production of nutrients showed up twice in the thread...I was just bringing focus to what the GMO world is actually focused on outside of educational facilities and single-staple-crop area crops where nutrient enhancement is more in play (even if the results may never see the consumer market).

Unless you want to count Al toxicity resistance as a nutrient concern, there's not a lot of work being done with nutrient interaction and GMO, especially by the major players.

ceth, I realized after I posted that my meaning would be easy to misapprehend: I didn't mean to say that my homegrown produce isn't indeed good for me, but that it might not be as superior as I had thought.

Luckygal, my interest in mineralizing is not so much about making the produce healthier for my diet, but rather is based on a supposition that some problems with serious infestations by herbivorous insects might be a result of excessively low elements. Also that drought stress could be reduced by correction of soil nutrient imbalances. I don't know how much "mainstream" scientific studies have backed up this idea. Not having yet read the 1975 paper linked in the OP I am hoping it will touch on that subject.

"Keeping one of these threads on track is like herding cats."

Herding cats is much easier. With cats bait, treats and teaser toys work wonders; not so much in public forum threads.

This post was edited by TXEB on Fri, May 3, 13 at 22:42

So reading the section on different elements, it appears that the strongest links between mineralizing soil and eventual human nutrition are for Ca and Zn. No specific mention of increased vigor and insect resistance in plants due to mineralizing.

However, the section on S reinforces my belief that low S is a likely culprit in vulnerability to insect attack in crops. In this regard I would rather use langbeinite than azomite, but the former has proved too expensive to use in much quantity. The results are very apparent, however.

Following up on the general issue of organic vs. "inorganic" soil amendment, there is a very good discussion on the matter beginning on page 46 of the first reference (page 51 in the pdf file).

pnbrown - my take on plant nutrition/health and pest/disease resistance is that, with all other things being equal, the healthiest plants stand the best chance of resisting and fighting of pest threats. In my experience that seems most applicable to insects, less so vs. disease. So, disregarding the issue of human nutrition, optimally nourished plants should hold up better under pest threats. As far as specific elements to emphasize, I believe a couple of the chapters in the second reference provide a more complete view of the complexities and interrelationships. In my mind, there is nothing to emphasize other than proper balance of all the nutrients. When we amend we really need to consider everything we are adding (e.g., for langbeninite we also need to consider the impact P and Mg being added, as well as the S).

S deficiency can weaken plants, but there's nothing special that makes it a vector for fighting off disease. S is crucial to chlorophyll production...deficiency can mimic N deficiency rather easily. S deficiency will show up non-translocated, though...aka, you'll see the deficiency symptoms on newer leaves rather than older leaves sending the S to new growth. On high S feeders (such as cruciferous crops) you'll see more extreme symptoms such as red/purple discoloration of leaves (similar to P deficiency) and leaf cupping. These plant weaknesses open the plant up to disease rather than them protecting the plant...it's role is chlorophyll production is crucial.

A deficiency and/or toxicity level of almost any micro can open a plant up to weakness. Ca deficiency will stunt plants in meristem areas (plant tips and roots)...Zn deficiency will cause thin-shaped leaf clustering at the top of the plant eventually leading to chlorotic/necrosis in leaves....Mn deficiency will lead to root/shoot growth rate slowing because, like S, it's an important part of the photosynthesis process. In this case it causes competing nutrients (especially N and P) to accumulate in tissues and open a plant up for disease thanks to a variety of features such as high-N plants being attractive to some disease-spreading pests and weak plant photosynthesis giving the plant less "life" than it would like to thrive.

There's many things in play and there is no "most important" nutrient for fighting off disease. If every essential element isn't in play (macros and micros) then you're setting a plant up for an imbalance that can weaken the plant...some more-so than others, but they're all essential to some degree.

As far as the multi-thread mineralization with rock dust thing goes...I really don't understand it unless you have a very long term plan, soils that lean toward acidic, and a high clay profile. It takes an extreme amount of breakdown action and nutrient holding capability (clays serve this purpose) in order to make any of it plant available. It will be present in some soil tests, but not in the soil solution as a plant available nutrient. It can take many years of weathering and action for these minerals to cleave off enough to exchange with clays or make it's way into the soil solution. It's not useless, but it takes a long time, the right conditions, and minerals that can hold/exchange the nutrients once available.

Would using synthetic fertilizers to grow food in subsistence gardens a sustainable practice? Could the very poor people in many third world countries afford to purchase synthetic fertilizers to grow the crops they need to subsist on? is it a good idea to promote the use of Genetically Engineered seeds by subsistence farmers that can hardly afford the seeds they now need but cannot afford? Would it not be better to make open pollinated seeds available to these subsistence farmers so they can save seeds to grow food next year?

Kimm, did you post in the wrong thread?

TX, I agree, one would should only use sul-po-mag where all three S, K, and Mag are appreciated. In these sandy leached soils S and K will hardly ever go amiss, especially K for a root or tuber crop, and Mag is not generally high around here except where there has been recent chronic dolomitic liming.

In some (many areas) there is no good way to adjust pH in soil. Liming soils that are too acidic is too-expensive to impossible given local resources. This is why developing Al toxicity crops (both natural and GMO) are a huge area of research.

The major problem in many areas isn't buying a huge bag of synthetic N (which is relatively cheap)...it's the total lack of access to cost effective pH adjusting materials. Agricultural fertilizers are rather cheap even in extremely poor countries...much cheaper than herbicides/pesticides and extremely much more cheap than pH adjusting materials. A 50lb bag of synthetic fertilizer can go a long way...50lbs of pH adjusting amendments will barely do anything to a large cropping system.

A bigger problem is native/subsistence farmers growing for the international market. It brings more money, but it generally leads to some very horrible land management practices for the sake of money (and less local availability as land is snapped up to grow these export crops). We're seeing this right now in Bolivia with quinoa farming destroying land for the quick buck. It's gotten so bad that their president is warning farmers that there will be no "bail out" for them exchanging the health of the land for a quick buck so they need to start considering this issue.

NC, regarding the broad-spectrum rocks, I believe there is the possibility of big differences between rock types, as we just are starting to explore, in terms of release. The langbeinite, for intense, supposedly contains some of the nutrients in salt form. I believe the same is claimed for azomite, many of the minerals are in some salt form and hence the release is far quicker than with the powders of more typical rocks.

I my so far limited experience this has been borne out: generally zero observable results from the addition of granite dusts, seemingly some results within one season with azomite, and I believe it is beyond debate that such things as langbeinite, greensand, and K-zeolites give quick results, yet more lasting than with manures or high-index synthetic salts. perhaps it is no surprise that these latter materials are expensive, while granite dust is generally free at points of production.

Not all rock dusts are created the same f'sure. Some will break down quicker than others. I don't think they're useless...I just think considerations such as how quick one needs them to be effective and clay content to hold/exchange those released nutrients need to be considered.

It's one of those "do now/expect later" amendments. Too many are marketed as miracle or "what THEY don't want you to know" amendments, though...and the price some are sold at is concerning. The push on them for use in container mediums by some companies/distributors I have special reservations about...not because of harm, but because of limited-to-no effectiveness.

Here's what gets me about the rock powders, and I'll use Azomite as an example -- 89% of what you get with Azomite is silica, alumina, with calcium, magnesium and sodium in whatever salt forms they exist within the aluminosilicate that it is. The amount of other nutrients and "trace elements" in the mix is quite small, and as illustrated in another thread when they are applied as directed the dilution effect means even if they were readily available the amounts you are actually adding are likely to be very small relative to naturally occurring background levels. With more silicate rocks the availability will be further reduced. So unless someone can demonstrate a real, measurable effect from a well controlled study, spending money of rock powders as a means to "mineralize" soils seems to me to be a waste as well as most probably ineffective. All of that is before we consider all the things that can come along with some of the rocks deposits that we don't really want to reinforce in ag soils, and that are often in greater abundance in those rock powders/dusts than the ones we know to be beneficial. The good news is that for the same reasons that they don't make sense to me as meaningful ways to add micronutrients and trace elements, they probably aren't a threat either.

TXEB: I was looking forward to reading the article, clicked on the link at the beginning of this post and my virus software immediately warned me about the link, won't touch any more links from you with a ten foot pole, too bad.

Anybody else have the same issue?

Michael - I just tried the first link, which had been corrupted yesterday after it was posted. Did you see the banner in bold under the link(GW tech folks are trying to figure out how/why html coded links are getting corrupted)?

After some work by them yesterday, it seemed the problem had been resolved. I attempted to edit the post this morning to remove the banner and the corruption in the link reappeared, so I left it unchanged with a warning banner.

The original link now seems to be working. Kaspersky 2013 says the file is clean, and the file comes from a UC Davis server. Scroll down from the top and you will see where I differently posted the link to the article.

For everyone's safety I will just unlink the reference and leave the note to look down for the link. Should be done in a minute, or so.

It's not me - it's something funny going on GW's servers. They tell me they are working on it.

I had no trouble linking to the first article soon after TX posted the link.

Regarding the dilution effect - I think this explains why in most soils materials like Azomite are not worth the expense at large scale. Probably much better from a long term perspective would be to get very large amounts of some nearby stone dust if it were available sufficiently pulverized. One reason I am trying to do side-by-side tests of Azomite with a local farmer is that he uses soils that are much superior to mine minerally speaking, they are a well-drained yet silty/clayey loam. I'm curious to see if there will be much notable effect of any kind - yield, appearance, resistance to insects, brix levels, etc within one growing season on a more superior soil.

pnbrown - it will be really interesting to see what your tests return. You may be breaking new ground here.

All critical to any kind of study like that are the controls. They should be identical in every way except for the variable that is being tested. The soil should be the same, it should be handled and treated the same, the plants should be the same, irrigation, environmental exposure, etc.

If I understand what you will be doing, you'll have two variables -- the Azomite and the soil. You will need controls for both. Others may have a better suggestion, but I would think the control should include an inert additive used in the same amount. I understand Azomite correctly, and I well may not, it's an aluminosilicate base. I can't off the top my head come up with a easy to get cheap, clean comparable material. So I punt to a reasonably clean, cheap silica - sand. I would think adding a comparable amount of fine play sand as a control additive would be worthwhile. I would also have a comparable control bed (two controls per soil case) where nothing is added, but everything else, including tilling/mixing action, is the same.

Could be a very, very cool study.

Well, the comparable controls will be large - effectively the majority of each planting. For example, if he does 500 feet of particular bell pepper variety, maybe 50-100 feet will have azomite added. The way it will probably work is after he has applied his dehydrated chicken manure and rotovated it in, I will come along and scatter the Azomite. it gets complicated where beds will be formed and covered with fabric, as for peppers and tomatoes, melons, etc, because I will have to follow behind and apply the azomite before the bed-former comes. Then there is the potatoes, where the planter also applies the fertilizer, so we'll have to make an outside row and apply fertilizer and azomite by hand, and plant by hand.

Short of the long is that we'll be lucky just to get azomite in place on a half-dozen crops, let alone additional controls. Though I do appreciate the logic of trying to eliminate all variables.

I am incredibly busy at work and I have been unable to read all the materials TXEB provides. I see PN is about to do some testing. I think this needs to be addressed on a matrix, soil type versus vegetable type.

Example: I used to live in acid sand (5.5). With lots of manure, it grew exceedingly tasty tomatoes, but the brassicas were inferior. Now I live on top of limestone mother rock, with high pH (7.6), and extremely high Ca and Mg. The tomatoes are inferior, but the brassica (roots and leaves) are fantastic, and I suspect also nutritionally better since I get many key nutrients from them (I eat minimal grains and dairy now). A coarse look at the literature provided showed results for grains, but brassicas are (almost) whole plant eating, which puts another complication in the whole assessment (that is, nutrition in parts of the plant, fruit and seeds, versus whole plant).

Good points, Glib. So it may be that an amendment such as azomite will benefit one type of crop more than another.

Speaking of, we got the potato test in place today, finally. I applied one 44-lb bag of the pelletized azomite to a double row of russian banana fingerlings, about 75 yards of it. That came to more than double the recommended application rate. It's the outside row of many rows of the same variety to serve as the comparable; all have dehydrated chicken manure applied at the same rate.

This after a couple of hours fussing with the 1950's era Oliver two-row potato-planter to get both sides working. Quite a machine to still be functioning after many years of zero maintenance - amazing really.