Peter, thanks for the laugh, " I grow cover crops when I have the energy". I can relate, brother. Try the covers this way, leave more in cover fallow than crops. For me the covers are pretty much plant, maybe irrigate once and walk away, the veggies are much more work. So, the more I leave in cover, the less work I have to do that season. My warm season cover is soybean, cool season is oat. Both, if planted at the right time and spacing will out pace the weeds smothering them out.

Peter, no doubt, given enough time and enough fallow and enough plant diversity and some food can be produced without fertilizer. Even with poor soils.

The fertilizers come into play for any operation that wants to make a profit. Can't be done without them, short of a very dramatic nutrient-mining scheme, and those were pretty well all done in the last couple of centuries, right?

Michael, do you know of some such experiments?

Some points that might be helpful to a broader understanding:

The OP said, "Organic soil amendments are great, use them wisely as their misuse can lead to anywhere from a negative crop response due to excessive salts to increased yields and crop vigor." "Vigor" is a genetic trait - an organism's ability to resist strain. VITALITY is a measure of how well a plant is able to deal with the cultural hand it is dealt. A plant can be vigorous, but still in poor vitality an d dying from the stress/strain of poor cultural conditions.

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"SALT" is not a plant's enemy. The nutrients plants get from the soil are absorbed ass salts, so if we were really feeding a plant when we fertilize or add organic soil amendments, we could accurately say the plant's diet consists of salts.

*****************************************************************

The numbers on a fertilizer package are not necessarily an accurate indicator of the actual weight of specific nutrients the fertilizer contains. For instance, 20-20-20 does not contain equal %s of N, P, & K. It contains 20% N, 8.6% P, and 16.6% K; this, because P is reported on the package as P2O5 and K as K2O.

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Mr Clint said,
"Organic fertilizers are:
* The food that feeds the soil microherds that indirectly feed the plants", but it can be pointed out that soluble synthetic fertilizers feed the plants, and in doing so feed soil flora/fauna that help feed the plants. If you imagine 1 plant in an acre of sand you should imagine most of that acre would essentially remain an organic desert with the exception of that single plant's rhizosphere. The common misconception is that synthetic fertilizers poison soil life, but the fact is, synthetic fertilizers increase the organic mass in soils, even if only by increasing plant mass, which in turn makes an exponential difference in biotic soil populations.

Something I wrote a while back:

In my gardens and beds, I adhere pretty strictly to the idea that on an ongoing basis you should use organic products/soil amendments that build the soil structure to minimize the need for soluble (read synthetic) fertilizers and nutrient supplements. That said, there are times you NEED individual nutrients to complete the assortment of essential nutrients plants take from the soil. If you're limited by a rigid 'no chemical' ideology, you either deal with the abnormal and sub-par growth or wait, while you hope adding more organic matter eventually solves all the issues. If you are NOT limited by rigid ideology, the issue is easily solved with a soil test and the addition of the appropriate nutrient(s) via a chemical compound like potash, various nitrates, phosphates, etc.

There are extremists at both ends of the organic vs. chemical approach to gardening. Some never think about the soil, believing it ok to keep adding chemicals to ‘hopefully’ produce growth. Others would never THINK of using a chemical and will chastise anyone who does. When it comes to my gardens and beds, I'm in the middle, but as noted I do lean quite heavily toward the organic side, though I stop short of telling anyone what they must do to be a good gardener. ;o)

Where container culture is the topic, soluble synthetic fertilizers get the nod from me - hands down. They are easier to use; we know exactly what nutrients your plants are getting and when they are getting them; delivery of nutrients does not depend on the activity of soil organisms whose populations vary in boom/bust cycles in containers; you're using a soluble product, not an organic soil amendment that has the potential to clog valuable macro-pores; you needn’t worry about soil structure, because if you’re smart you’ll have built it into the medium before you planted in it ….. but let’s save the container soil topic for another day.

I mentioned there are those at one end of the spectrum who would never lift a finger to improve their soil. Adding organic matter to their soils would be as foreign to them as adding exercise to their life’s itinerary. On the other end, are those who stand ululating and hand-flapping (credit to Dan for that one) at the very thought of anyone using Miracle-Gro. From the plant’s perspective, both extreme positions are ridiculous, and from my perspective, both extremes are unnecessarily self-limiting. The plant just wants to grow to it’s genetic potential. To do that, it needs a full compliment of the nutrients plants take from the soil, and it doesn’t care if they come from compost or Miracle-Gro.

Perhaps a more logical approach to plant nutrition might be to look at soluble synthetic fertilizers in the same way we look at IPM practices. Use the most naturally harmonious method/product we can to bring plant growth or yields into the acceptable range. I realize that in most cases, we can do this by adding more OM, but not always. Often too, time is a consideration. We may have someone who wants to plant immediately, in soil that is deficient in one or more nutrients. We probably shouldn't expect someone to forgo their own freedom of choice and wait two years or more while the soil is fortified/improved only via the addition of organic matter.

There is a technical difference between a fertilizer and a soil amendment, but even that point eventually becomes moot from a strictly nutritional perspective. Plants take up elements that are dissolved in the soil solution and in ionic form. What they take up are salts. The large molecules that make up hydrocarbon chains in organic fertilizers/soil amendments cannot be taken up by the plant unless the hydrocarbon chains are broken down into elemental/soluble form by soil organisms. At that point, the elements from soluble fertilizers are the same as the elements from organic sources, which is why the plant could care less. At the point in time where nutrients are assimilated, they are ALL soluble and in elemental form, regardless if they came from a dead fish, compost or a hose-end sprayer.

If we could only achieve happy healthy plants in a soil teaming with life, using only organic soil amendments and fertilizers, how do we explain hydroponics? ... no medium, or an entirely inorganic one, and only soluble sources of nutrients. At the very least it suggests there is a middle ground in which everyone can seek their comfort level. I’ve been growing perfectly healthy plants in containers in a medium whose only organic fraction is 1/3 or less pine or fir bark; the rest of the ingredients are large mineral particles like Turface and crushed granite. I’ve used ONLY soluble fertilizers in these soils, with the hundreds of pictures I’ve posted here at GW serving as concrete proof that happy, healthy plants can indeed be grown using only synthetic soluble fertilizers if the soil structure is favorable …… which leads me to the reason for writing this:

Colloquially, the term 'organic' formerly applied to things once living, but even some plastics contain carbon and are considered organic compounds as well. It really is misleading when we throw the word around w/o much consideration, but I admit to being guilty of it from time to time as well. Technically, urea, ureaformaldehyde, isobutylidene diurea, and crotonylidene diurea (forgive me if the spelling is slightly off) are all organic molecules, and actually do an extremely good job of feeding microbes, which reinforces the idea that synthetic fertilizers are getting framed for the microbial murder rap that should be hung on the effects of reduced OM in the soils. The microbial murder rap should be hung on the effects of reduced OM in the soils; purposely redundant so it couldn’t be missed.

It's a vicious circle; mineral soils can support optimal plant growth (nutritionally speaking) only if enough young decaying matter is returned to the soil regularly and frequently. Prairies and forests are virtually self sustaining because all vegetative matter is recycled back into the soil. If we regularly mow and bale the grassland, or log off the forest, nutritional deficiencies are assured as a result of our removal of the OM that would have provided future nutrition - thus the tendency/need for us to adhere to the practice of replacing the lost nutrients with chemicals.

In our gardens/beds/lawns ..., we can add compost or other OM to replace the vegetative matter we remove and use or discard. For more than 20 years, I've used compost regularly in the gardens/beds, and apply fine pine bark mulch 2-3" thick, usually every other year. I have extremely healthy soil and rarely find it necessary to use anything synthetic.

You can find opinions all over the net that chemical fertilizers are laying waste to the landscape, and wiping out microbial populations faster than chocolate disappears from the candy dish in the family room. Are these opinions based on political views and a radical ideology, or warranted and based in fact?

In research by Texas A&M University, intensely managed (read ‘managed using chemical fertilizers‘) sports fields with mostly a sand substrate showed no shortage of soil life. That is there were 10s of millions of bacteria, and 10s to 100s of thousands of fungi per cubic centimeter present in the heavily managed soils. Part of the study included measuring soil life in 11 inches (deep) of pure sand, with no organic amendments whatsoever, over which washed sod was placed. As the sod 'grew in', soil life populations increased almost immediately, 10-100 times .

Soil life populations just sort of hang loose, waiting for something they can digest. If they don't get it, they die and feed off each other. When organic matter is introduced into the soil, they break it down, and their numbers increase. When they've consumed the organic matter, they die and consume each other, but the base population remains, ready to spring into action the moment more organic matter becomes available.

What do fertilizers do? They make plants grow. Sure, extremely high concentrations of chemical fertilizer poured on the soil in volume might kill some microbes in the immediate area, but the o/a affect of chemical fertilizers is actually an increase in microbial populations through increased plant growth. You need only look to the fact that the rhizosphere (root zone) of plants is such a popular gathering place for soil biota to see increased plant mass promotes a marked increase in soil life. It's actually the continual 'taking' of OM from gardens, agricultural fields, lawns ... w/o replacing it that reduces or inhibits the communal activity of microbial populations. Even then, they're virtually never in short supply and are ever ready to bounce back ... if you just give them something to eat.

None of this addresses the hot button political, ideological issues too many wish to export from their own value set, other than the fact it points out the folly in occupying the margin’s extremes. Again, I'm pretty pragmatic and results oriented, so I tend to approach this subject from a plant/soil perspective and leave the politics to the ideologues. My personal view is that in the o/a picture, a chemical fertilizer or nutrient supplement judiciously and responsibly applied to our gardens when it's found to be needed isn't the earth's end; and I prefer to use my own sense of right/wrong to set my course, rather than be told what I need to do to be a good, responsible student of husbandry.

That said, avoidance of unnecessary chemicals in the gardens/beds to the greatest degree I feel is reasonable, is still my normal MO. YMMV, but options are good, and I prefer to keep them open.

Al

Hi folks, I'm not an ideological theorist, I use both organic and conventional methods. So I won't engage directly regarding some of the hypothetical examples/situations. :)

My preference is to grow organically because I've found the plants to be generally more sturdy, with denser plant structures, which makes them less desirable to sucking and chomping pests and also diseases. Water insoluble fertilizers along with OM have increased my soil tilth/structure. Some of my plants, blueberries especially, taste better after going organic. Cost savings and carbon footprint equations don't factor in for me. Those are nice to haves, but not a primary focus. All gardening is local and your mileage may vary.

Al, thanks for the interesting post.

One problem I have with prepared synthetic fertilizers is that the traces (if any) are usually in oxide form, which can be unusable to the plant. Citrus fertilizer, as an example.

I have said before, and will keep repeating this as long as I can, people that use synthetics to garden, even in conjunction with organic materials, are not organic growers. One can attempt to justify the use of synthetics all one wants but the use of any synthetic product means that person is no longer organic for a fairly long period of time of not using any synthetic product again.
To quote what is printed, clearly, on the first page of this forum, "This forum is meant for the discussion of organic gardening. Organic gardening is most easily defined as a philosophy that stresses the use of naturally occurring substances and friendly predators and avoiding man-made chemical fertilizers and pesticides. This is the philosophy which guides this forum."

This post was edited by kimmsr on Sun, Nov 23, 14 at 6:15

I'm not sure that GW's intent was that only people who hold the same views as kimmsr should be allowed to make comments on this forum - especially when the comments are germane to the OP. The more options growers have - the better, and even if they choose to allow a particular ideology to govern their choices, the more reliable information they have the more clearly they will be able to see both the limitations and attributes of those choices. I'm all about people being able to choose for themselves and not be made to feel they're a square peg trying to fit themselves into someone else's version of a perfectly round hole.

The OP is about organic fertilizers - a topic fit for the forum; and when someone makes the point that it's not necessarily the boogeyman "salts" of synthetic fertilizers that destroy soil life, but the fact we aren't returning enough OM to the soil - that too is a topic fit for the OG Forum.

Al

"All or nothing" is not how everyone is going to garden organically.

Yes, they're not totally organic, but unless they strive for a total organic approach then it may not happen. People might find an organic alternative if it works or they're into it...but they might not.

Myself, I use artificial fertilizer in conjunction with my compost and plant litter regimes. Outside of that I am almost totally organic. I'm not getting hung up on being able to say "I'm 100% organic"...I'm not getting hung up on the 4"x4" small box of Miracle Grow that's 2/3rd empty after 5 years of use...I'm not getting hung up on that time 6 years ago, when after coming back from vacation, I used a "nuclear option" of spraying a crop that I would lose unless I controlled the pest issue immediately.

Think of the skills and techniques some are picking up as "harm reduction" even if you're not happy about it being totally organic.

"All or nothing ......"

Strong agreement from this quarter.

I'm extremely results oriented, so more concerned with how my plants perform than with whose club I'd be a fitting member for. I get great results in the gardens and beds using compost and lots of pine bark as mulch, and almost nothing else. In containers, I use nothing but 1 soluble synthetic fertilizer, because with the container media I use, it gives me very precise control over my plants' nutrition.

Al

Tapia:as indicated by the section you quoted from my post, I said, "salts" not salt. Salt, sodium chloride, is an enemy of clay soils with good structure as the Na will cause the structure to disperse, there goes the pore spaces, air and water infiltration. Excessive salts to the extreme will make it impossible for plants to uptake water. The salts are included into 2 categories , the anions and cations.

Oops, gotta go.

For the record, I'll restate:

"SALT or SALTS" is/are not a plant's enemy.

When an acid reacts with a base, you get a salt. Soils are rich in salts - if they weren't, plant life wouldn't be possible. Sodium and chlorine are both elements essential to normal plant growth, do the dose is the determining factor insofar as whether or not levels are toxic to the plant, which will happen long before there are soil structure issues. Neither sodium nor chlorine exist in nature in elemental form, and only when they combine are they considered a salt.

I agree that plasmolysis is the result of excessive salt levels, no matter the source of those salts. Sugar water can cause plasmolysis as readily as a table salt solution. So again, the poison is in the dose.

Al

Tapia: where do sodic soils come from if Na+ doesn't occur in nature?

We agree on concentration being the issue when considering salts in the soil solution. Yes, soils are rich in salts as are many irrigation waters making proper irrigation a necessity if one wants to manage their soil well.

Roots exude a weak acid that helps liberate the soil nutrients for plant uptake via the acid base reaction you mentioned.

Pure Na is an active metal and never found in its pure form in nature - same as Ca, one of the most abundant elements (5th? 6th?) in the earth's crust. When Na comes in contact with a water molecule, it produces a very strong exothermic reaction, during which hydrogen is released and self ignites. The H burns very brightly or creates a series of explosions. I haven't seen any of that in my garden lately.

I'm not seeing the point of this conversation or how it's relevant to the topic. You can easily verify what I just said by doing a quick search.

Interesting thread, though.

Al

Clearly there are those that come to this forum and comment that are not organic growers. No one has, except one of those, has mentioned restricting anyone's ability to comment just that those non organic growers should probably identify themselves as not organic, in the interest of veracity. Many of those non organic growers also do not appear to grasp many of the fundamentals of organic growing.
The bottom line is if someone uses, and/or advocates the use of, synthetic products they are not organic by any stretch of anyone's imagination.

This post was edited by kimmsr on Tue, Nov 25, 14 at 6:59

Plus there are those with confused ideas who comment here. I just ignore what is not useful to me.

Many people understand the fundamentals of growing very well, and are much more qualified to choose the path that best serves their goals than someone else intent on filing everyone under a nice neat heading. Some growers even understand what limitations working under the restrictions a rigid ideology can impose, and choose to modify that ideology somewhat so it is less limiting and to make goals reachable.

BTW - I'm not advocating anything. There are a lot of commonly held beliefs that turn out to be myths that don't hold water under even casual scrutiny. The idea that salts in synthetic fertilizers are necessarily a bad thing can afford a little closer examination, even on this forum. Information and insight that either makes people more secure in what they believe, or gives them pause to more closely examine what they though to be true is a good thing.

Al

Tapla: salts can be detrimental in excess to soil structure ( Na+ in particular) and a soil's conductivity. Saline sodic soils are a real bummer.

Yes, elemental sodium doesn't exist in nature in an oxidizing environment, however, it will readily lose an outer shell electron to form Na +. The Na + is what is rough on soils. How this ties in to the OP, it doesn't, as with many GW posts, this one has wandered off course.

Back to the rough point of my post here - if I have to move a ton of materials to my gardens using yes, non - renewable resources, when I could use another material that weighs only 150 lbs thereby requiring far less transport resources, why would I go the ton route every time?

I won't name names but, one poster frequently interjects their one big, personal belief that comes out the same every time it ends up in a posting regardless of the post's topic, kinda amazes me. I promise to try and stay on topic and try to explain why my beliefs posted are on topic.

I should like to make expliciit what I previously implied: the nutrient density that matters is the nutrient density in the vegetable; the nutrient value in the fertilizer is a means to the end, not an end in itself. Now it gets contentious: I further maintain that the highest nutrient density in vegetables -- the "excellent" numbers on the Brix chart -- can only be obtained by using organic practices. If someone has results that contradict that assertion, I would be happy to recant.

In response to pnbrown, it does seem entirely reasonable that one can't remove crops without restoring what they take out of the soil. I do apply any mineral that comes up short on the soil test; fortunately that's less frequent than it was 40 years ago. However, I must mention biodynamic practice. One of the principles is that one is self-sufficient, not importing any fertility from outside the farm or garden, Another principle is that keeping animals is an essential part of growing crops. But one would suppose that their role would be to capture and recycle existing fertility, rather than increasing it. But biodynamic growers report increasing nutrient density as time passes, which is (a) counter-intuitive, and (b) worth looking into. Regards, Peter.

Peter, I also believe that brix numbers convey useful information - what that information is, exactly, is apparently a matter of considerable debate. I imagine you have read some of those debates in these forums and elsewhere.

I also agree that what matters for us is nutrition-per-bite (as I call it), rather than levels of plant-available nutrients in the soil, etc. IME, high brix levels are highly correlated with the age of the plant, IOW, how long the plant has been able to build root/fungal/bacterial relationships. For example, I have a 3-4 year-old chard plant in my solar bunker and while the plant itself looks rather haggard and endures very tough conditions during the summers (heat, low light, no precipitation or irrigation), nevertheless the fresh leaves are so loaded with salts that one can quite easily taste them. By late winter the leaves are thick and leathery and have high brix numbers. I have made virtually no additions to the soil in that bed since I built it 3 years ago.

In an isolated situation where refined salt was not available I believe that it would be possible to get sufficient sodium chloride in the diet by growing such accumulator plants in locations where precipitation is restricted.

Back to the point: why burn more fossil fuels than needed to get the nutrients into the soil that will grow the plants that produce the brix numbers some are focused on? Plants don't care where their essential mineral elements come from as long as they are present in sufficient amounts at the right times.

That is not saying organic amendments are useless or unnecessary, definitely not.

One goal is to replace what a crop removes from the soil. There are tables showing that for many crops with given yields, if I can find one or more I'll post them.

We have to take into account the fossil fuel used to get our soils into a productive condition and keep them there. I'll keep adding o.m. to impove tilth, structure only and to a limited extent, fertility from the not very nutrient dense organics.

Michael, your point is entirely taken with me.

I would be loath to use a high-salt fertilizer in a broad application without applying simultaneously with some form of sequestration, whether well rotted compost, char, humate, etc. I suppose in soil with a high clay and/or silt fraction and high SOM I might go with an undiluted application especially in the case of stimulating a cover crop.

I have witnessed the results of constant rotary tillage and application of dehydrated chicken manure (which I believe is effectively a high-salt fertilizer) for many years on a prime soil type (silty-clayey loam). The SOM is very low, resulting in severe compaction and drying in summer heat. Without surface irrigation the soil becomes concrete and useless.

An example table of nutrients removed by many vegetable crops is shown below.

Here is a link that might be useful: Nutrients table

Here is a very on-topic and very excellent online book reprinted from some decades ago. I think we will all learn a great deal from reading it.

Here is a link that might be useful: soil fertility

pnbrown: The link you posted on soil fertility is an updated version of something I've used quite a bit in an earlier form and found very useful. I didn't realize this new version was available. I appreciate the strong pro-organic approach the author takes without being dogmatic. The approach is to use fertilizers that make sense, and not fertilizers that meet a preconceived notion of organic. In some cases, like that of superphosphate or triple phosphate, the author makes a clear case for the use of some materials not currently on the list for certified organic cultivation. It is useful to have concrete data on the materials discussed. It will be interesting to see if, in the future, the certified regulations start to follow more of the philosophy presented in the link. In particular, the approach to the use of synthetic vs. natural materials in cultivation is one that I feel could really benefit many growers who strive to grow organic if a similar approach could be taken in the regulations. Doing something that makes agricultural, economic and environmental sense is, after all, the real goal of most organic growers.
Renais

It's a very impressive assemblage of experience. I am not done reading it. So far I am most impressed by the claim that humus cannot be built using soluble N fertilizers. Which would surely include dehydrated chicken manure. That is just what I see everywhere: soils that get regular tillage and use of N fertilizers steadily lose humus and after some years have almost none left. The result regardless of soil type is something that will produce nothing without large fertilizer inputs for every crop.

One of the important changes I see happening in conventional growing is the increased examination of no-till or minimal till as a growing practice. These methods can help reduce oxidation of organic constituents of the soil, and thus help to maintain or enhance the soil structure and moisture retention characteristics. The net result is often less need for a N input, because the decaying crop residue makes a contribution. The link pnbrown provided above does a lot to illustrate this point for N. There are other things that can be done to reduce environmental impacts and improve agricultural yields related to other crop nutrients. One of the most interesting I see is the potential to utilize additional industrial waste streams as agricultural inputs. Two streams that I think are particularly interesting are waste or exhaust acids from some processing which can be used to treat otherwise ineffective ores for K and P supplementation, and paper processing waste, much of which is now composted, and used locally. With more research, the paper waste stream might be developed into an input to controlled environment growing to replace perhaps some of the peat and coir currently used.
Renais

I think he is going further than that, renais: as I read it he is saying that one cannot build humus and use soluble N inputs. Mutually exclusive, IOW.

pnbrown: "I think he is going further than that, renais: as I read it he is saying that one cannot build humus and use soluble N inputs. Mutually exclusive, IOW." I agree with you, and did not mean to imply otherwise. In fact, I use an addition of N fertilizer to some of my composting containers to speed the decomposition of organic matter, knowing that there will be somewhat less humus produced in the end. My organic waste stream is so large that rapid decomposition is much more important in compost than is the pre-humus content of the finished product. My growing soils have sufficient organic matter inputs. I hate the idea of sending any organics to a landfill, so I do quite a bit to process them in situ. I have also noted that I can effectively lower the organic content of my soil if I till a lot and add a lot of N fertilizer. Both the tilling and fertilization can be/are overdone by growers, especially some of the small truck farm operations. An enthusiastic and well-meaning truck farmer can thus spend too much in both time and materials to have in the end poorer soil. This is a place where education can really make a difference.
Renais

Here in the blow sand plains of central WI, we have built up those sand with huge amounts of organic matter with the only major inputs being soluble Nitrogen fertilizer along with other synthetics. Lots of irrigation was the other element input to these blow sands, relative to plant growth.
This OM came from the residual plant material left behind after harvest and worked back into the soil to over winter.

My question is why would this plant material not become humus, or contain humic acid?
It doesn't make sense to me so an explanation would be appreciated. :)

Maple:

"we have built up those sand with huge amounts of organic matter "

What does this mean? Percent OM by soil tests over long periods of time?

Because the inference here is that SOM has greatly increased over time, in a poor soil type, solely by means of crop residues. That is pretty well directly contrary to all experience and common sense.

If it were true we would have no soil problems anywhere in the world where rainfall is adequate.

pnbrown, it isn't about adequate rainfall only but the inclusion of fertilizer to make plants create OM. Cover crops in the Fall tilled in at Springtime and the soil filled with huge amounts of potatoes and ALL the roots and tops that remain, with more NPK on the way for beans,before the covercrop finishes the season.

This doesn't go against common sense it IS common sense to all the farmers who have built up less than desirable soils into highly productive soils. :)

Really, I can't buy it. Not in "blowing" sand. I guess I'll have to come out and see and you'll need to show me before pictures and soil test results.

That is an interesting perspective and mental image you have of soils.
There are many theories about, How Soil is Formed. The ones I learned about all had to do with plants living and dying in various stages of weathered rock and organic matter building up in it. Of course they always said 1" every 1000 years back then, but still SOM comes from OM.
Why does the Texture being sand make a difference in your mind? Is there a difference in soil building for the Texture of clay?

Some of you may be interested in the info. Way down low in this link on growing spuds. Milk Ranch Specialty Potatoes is located on very sandy ground in The San
Luis Valley of Western Colo.. They have been producing both conventionally and organic seed spuds for decades and from my experience produce an excellent product. No doubt in my mind they know how to grow organically on sandy soils. Unless he sold out, the owner is Craig Rockey.

Here is a link that might be useful: The Potato Garden

I was thinking the same about your perspective, as it happens :). I will continue to insist that it is not possible to both build SOM and take a significant crop of the land on a regular basis, with only soluble fertilizer as an input. This is my opinion based on everything I have done, seen, and read.

Start with pot of vermiculite or mason sand and grow any crop you want with water and Miracle-Gro . Harvest whatever crop you planted, leaving the plant residue and have a season of ryegrass worked into the pot, afterwards.

Vegetative matter doesn't break down that quickly in a pot as it would in the real world field, but you should see how this pot would change over several years. :)

I think we're done here. I've done quite a bit of growing under all kinds of circumstances, and I've had my eyes open.

Pn: no doubt in the warmer climates it's tougher to build SOM or even maintain it growing crops largely with high density fertilizers like urea, given the right conditions, the soil MOs will really chew through the om converting it to humus. Warm , moist soils favor the process especially compared to cold dry ones. No-till grain farmers around here are finding after a few years of converting to no-till they don't need as many "inputs" because of the residue that is returned to the soil.

Mapler: very creative demonstration idea, my hat is off to you and I agree, it is possible to harvest a crop and build SOM. Another way to do that would be with interplanting like a legume with a row of tomatoes. For the first time last Fall, I interplanted oats with Berseem Clover for a cover crop to see how it would work. Next Fall I'll try lettuce, spinach and a few others with Berseem and see how it goes. For warm season stuff, I might try sweet corn with soybeans.

Thanks michael357, it is interesting that you bring up the seasonal differences and the issue of producing more raw OM than can be consumed.
I seems to me that in north central FL, the sand they have is very similar to ours in texture. While they also have irrigation and a mild climate their sands appear to sit barren all winter, until watermelon time.
If it was me I would have a market for cole crops or have that soil covered in some annual grass seed for green manure in the Spring.
We can see that the soil is a little darker at the surface compared to what the moles pile up from underground but should be much richer in color and fertility, IMO. :)

Mapler: you might be surprised at how warm it isn't around Gainesville, FL in the winter as far as trying to get crops, both cover and edible, through unpredictable frosts. I posted the link that if you put in calendar months and years of your choosing it'll output the temps and other data for Gainesville. Just looking at a month or two over a year or two won't tell you the real situation, the more you dig, the more you'll understand the realities down there over the long haul.
It's pretty easy to see why the citrus industry froze out long ago.
Hope I got the link right.

Here is a link that might be useful: NowData for Gainesville, FL

IME with xeric sand in florida, green manures are not effective because the decay cycle does not function as it does in moist soils. You can turn over green material in that sand, but it will not decompose in the way you are used to, instead it desiccates over a longer period of time. You will find the dried material still recognizable many months or even years later.

Thanks for the chart,
The average temps on that chart for January was 50s and 60s. I remember a few years back everyone had a frozen pipes problem, because of prolonged cold weather. That was considered to be in the 50 year cycle maybe even the 100 year cycle by the Old Timers that commented.
I remember being there in January and we had frost on the windshield twice but almost never after February 15.
Still could be very risky for huge farmlands I suppose.

It seems that home gardens would get going a little earlier, but maybe they don't like gardening the way many of us do.

My first year in FL was in Orlando, I remember having to scrape frost off my windshield to drive to work one morning. The next 8 years were in Gville with a few frosts now and then, on one morning it was sleeting so heavy it was accumulating on the backs of a herd of Brahmas I drove past. Boy did those beasts look miserable! Don't remember any frozen pipes but thought about it more than once.

Pn: the green stuff does take a while to break down as it is not too uncommon for the sandy soils to dry out for long periods during the dry season, add to that a lack of N laying around and there sits the material.

Quite so. I was finding bark chips and such in the garden soil 2,3 and 4 years after adding material. When I started keeping the ground always covered with dead and living mulches and never tilling is when there was some moisture and some very slight increase in SOM, and then I found I could grow certain crops to fruition with no irrigation at all.

Of course on a large scale such practice would be madly expensive and of low productivity.

Maplerr: did you notice for each month's worth of data at the bottom of the max and min temp columns they showed the column averages and normals for the periods? The averages are only for the temps that month selected and of course normals are self evident.

I love looking up that data for different parts of the country and looking way back for my own looking at trends. Our tax dollars at work doing something useful. Our local observer may be retiring soon, I hope to take his place except for the tornado spotting part :)

The chart was not very user friendly but I believe I had read it correctly for the rainfall inches/month since 2002.
My stays are typically during late Winter and drought has never even been a possibility during those years.
I suspect that they have normal and adequate rainfall, perhaps even more reliably than we do in WI.

El Salvador has a definite dry season in that it doesn't rain from November til March. I did experience a misty afternoon one time, however. :)

Lower latitude and generally dry air in winter = much higher evaporation rate from the sand as compared to higher latitude with generally moist cool air in winter.

That NowData site does take some messing around with to figure out, once you do it's a real treasure trove of info. If I can figure it out you can

Pn: the clay loam soil my raspberries are growing in literally eats up 2" of finely chipped bark every year now for the last 3 years and is turning into some beautiful stuff.

Yeah, that's the nice thing about clay and sufficient moisture, isn't it?

Pn: oh yes it is, feed and water it right and the soil MOs will eat the OM like a herd of hogs.

I wonder if my using only chipped bark with it's population of dried lichens and mosses helps vs wood chips. Seems to me it would. We heat the house with wood and as I grab wood off he pile lo bring in all Winter I full off the loose bark and pile it up to chip n the Spring.