Standards and Best Practices of ORG Dirt Science

'''This document is presented for readers who prefer this information all in one place. Portions of this document can be found in the alphabetical section at the bottom of the ROI Standards page. Individual titles will be presented under alphabetical headings as soon as is practical.

Readers of this offering should not be confused about the use of the word "dirt" herein, if this page is where you entered this site. If that is the case, then will take this opportunity to state this author's "position", to lessen confusion.

There are those in the realm of (soil) science, who say it is 'not correct' to refer to a soil-based medium as "dirt" such as http://csip.cornell.edu/Projects/CEIRP/AR/Soils.htm as only one of many examples.
I have no 'bone to pick' with any institution of higher learning or any agency that wants to regulate whatever... But as a Master Composter Instructor and a Master Organic Gardener Instructor, with a focus on training people how to amend 'the ground' and other places to raise plants, I'm simply tired of people (especially high school science teachers) telling me that I should not be using the word 'soil' in the context of my field of endeavor. Fine. So it's Dirt. Now leave me alone.

This author's position is: so long as natural (as nature made it) soil has been disturbed (changed) in any way by man - so that it no longer represents the undisturbed original, then that portion of (disturbed/changed) soil has become "soiled" and thereafter can be considered to be dirt.

It is this author's position that nature makes soil. Man does not make soil. Man makes soil into dirt. No such thing as man-made soil.
Whatever medium is capable of growing plants and is made by man, is dirt and not soil. If a natural state is soiled, it is dirty. If a medium is dirty and grows plants (and is not soil), then it is dirt.

On that basis, the rest of this treatise entertains ROI standards for amending original soils to increase plant growth, and making compost, and other forms of dirt for plants or containerized plant-growing mediums, all of which are termed dirt.

FRIENDLY

We all know that humans come with a variety of 'attitudes'. This author is no exception.

We should treat everyone as if they are our next door neighbor who is a State Trooper with a mean dog and a bigger gun than yours. So be nice.
Yes you can state your opinion, which this author does often, but please do it with as much respect as you can muster while communicating on this site.

If any reader thinks that this author has not been respectful in communicating my contention regarding 'the validity of dirt science', then I hereby publicly apologize.
I believe that attempts to explain my position on this site have been sincere in expressing my frustration with soil science for taking 'both sides' of this position for a long, long time as it pleased their particular present situation at the moment.
The word 'soil' has been bantered about to mean this and that and I'm really tired of 'soil' people telling me what is and is not 'dirt', in relation to how they want to define 'soil' at any given time.

AIR

Air is an essential component of soil or dirt for roots of aerobic plants. In aerobic soils or dirt mediums (not necessary for water-grown plants), air is required for healthy root growth. In plant-specific dirt prepared for general earth-based plants, the aerobic needs of plant roots and attendant microbe populations should be particularly considered, and there are certain components of mediums designed to accomplish that purpose - which will be covered in later sections.

Fresh air is also an especially important component of the aerobic 'hot' composting method, usually managed by the practice of 'turning' compost material through a 'screen' (nowadays, usually a section of galvanized chain-link fencing staped to a 2x4 frame).

One main principle of aerobic composting is called "gas exchange" since compost microorganisms intake oxygen and output carbon dioxide - and when CO2 builds up in the material - it WILL kill microbes and deter further rapid decomposition. CO2 is odorless, so the pile will not smell bad, unless oxygen becomes seriously depleted to the extent that anaerobic (not enough oxygen) conditions prevail. If feedstock is allowed to become anaerobic, the entire compost pile can become a smelly mess.

The amount of air in undisturbed soil can be quite low, especially if it has a high clay content, or if 'settling' has occurred (sometimes a factor of places where water is held), and be insufficient for growing many types of plants - which are growing quite well elsewhere in the same 'type' of soil. Local site-specific conditions prevail.

A prepared dirt mix may be formulated to accommodate growing plants with a wide range of requirements for air at the root zone. How much air? - that answer can vary widely, depending on what kind of plants are grown, but consider 'average' air content needed, to be in the 25% by volume range.

Various individual components in prepared planting media (dirt) have different capacities to hold air. A list of such components and their properties is offered in a separate section on this site. Plant growers should be attentive to the aerobic conditions in any media (particularly in containers), to ensure that a proper balance of aeration-to-moisture is appropriate for the plants they are growing, and particularly watching for conditions of dirt compaction due to overwatering containers.

Watering any growing medium can cause air to be displaced, whether in the ground, a compost pile or in a container.

WATER

Water is an essential component for almost all plants, and particularly those grown in containers and in sandy (doesn't hold enough water) and clay (holds too much water) soil and dirt.

The ability of plant-specific prepared dirt to retain moisture relative to needs of certain plants is even more critical, depending on the irrigation method used, which affects microbe populations as well.

On the other hand, amending soil in the ground (which can make it better, as a more friable dirt) can significantly change the air/moisture relationship and may require additional attention to water percolation and drainage issues.

The amount of moisture in amended soil (dirt) or prepared dirt mixes may fluctuate considerably based on different amendments used, to accommodate needs of growing certain plants. A 'target' moisture content in a prepared dirt mix should be in the 25% by volume range - more air for cacti and more water retention for plants that like to have their 'feet wet'.

One of the most common problem issues for growing plants is irregularity of watering. Different plants have different needs, so you should know what the expectations of the plants are, that you grow.

A prepared dirt mix may be formulated to accommodate varying plant requirements for water and an average 'target', is considered to be 25% by volume range for 'starters'. And by the way, do you know how to perform a 5-gallon bucket 'porosity test' to find out what the air/water content is?

Water for plants should NOT contain chlorine or any other microcide or heavy metals. To the degree that chemically-treated water (to kill microbes) is used, that IS the degree to which the soil food web will be damaged, making it difficult for microbe populations to survive, to provide nutrition to plants organically. While it was true in the past that chlorine products would dissipate quickly in contact with air - today's chlorine chemicals are formulated to be much longer-lasting in the presence of oxygen.

For a lot of 'greenhouse' growers, chlorine is a non-issue, because chlorinated city water is what they have, and they are not interested in removing the chlorine anyway, since they do not use a growing medium that utilizes microbes to make nutrients for their plants anyway - because they use synthetic nutrients.

OK fine. But for the person who purchases that potted plant, they should at least be made aware of the issues that they are "up against" when they get the plant home from the store.

OK - don't have space to "get into" that topic here, but look for that issue expressed in other topics on the More Soil-Dirt Topics page. Workin' on it...

The life span of an 'average' microbe is measured in MINUTES (not hours) and microbe ability to reproduce CONSTANTLY is the determining factor in population densities and diversity, needed to turn organic matter into plant nutrition within organic growing mediums that need clean water to flourish.

If organic matter, capable of holding up to 40 times its weight in water, is saturated with highly-chlorinated water at each irrigation, how would one expect microbe populations to make plant nutrition from it even if there was sufficient quantity of aged organic material in the growing bed or potting mix?

An activated charcoal filter placed on the water line is capable of removing chlorine, but pure RAINWATER, collected in a catchment from ground water, is the recommended standard.

Various individual components in prepared planting media (dirt) have different capacities to hold water, and some manufacturers recommend an organic surfactant (wetting agent) be added to irrigation water, particularly when foliar feeding. A list of such components and their properties is offered in other sections on this site.

Plant growers should be attentive to the moisture-holding conditions and complimentary air-holding capacity in any dirt media, to ensure that a proper balance of water-to-air is available to the specific plants being grown.

HEALTH OF DIRT -'(Planting Media, whether in-ground, raised beds or containers)'-

The basic principle at work in making dirt, emphasizes a holistic approach to plant health by nourishing plants organically via microorganisms contained in organic matter, instead of feeding the plant directly with water-soluable nutrients (preferably organic, if such regimen is used). Healthy dirt IS the key to healthy plants - not synthetic fertilizers that can damage dirt, particularly raised in containers.

When planting in the ground, there are two ways to look at the soil-plant relationship:

  • determining what condition the soil is in and choosing appropriate plants for that soil type; or
  • replacing or amending (which makes soil into dirt) for plantings that would grow best in new conditions.

For land owners that have significant depths of either 'sugar' sand or compacted clay, the option to select 'native' plant species may be quite limited, depending on a lot of factors such as soil pH, plant nutrition values, etc., etc.

Because native plant selections for a given area are not differentiated with basis for changing soil conditions in any given area (based on soil maps), it is easy to go wrong when planting 'natives'. Climate is NOT the primary requisite for recommending planting native ornamentals. Soil types and textures can change drasitically within less than a half mile.

A native plant that grows well in a sandy soil will not survive in a clay soil just a short distance (as the crow flies) - as in the case where this author resides.

Some Master Gardener 'experts' in native plants are ESPECIALLY bad about recommending native ornamental plantings "generally" to the public, without even providing basic soil mapping information, or telling property homeowners that the type of soil they actually have is very important - or telling them where to locate the information to find out what kind of soil they actually have, and how to excavate a deep enough (root zone) sample to determine what they ACTUALLY have available to plant in...

One way to determine if a soil needs to be amended - is performing a bulk density test.
To perform a bulk density test, visit http://soils.usda.gov/SQI/assessment/files/chpt4.pdf
Soil respiration and infiltration/percolation tests can also be conducted as well as a number of others.

But in this author's opinion, the best test takes one year. Grow an annual plant in it, that is supposed to get 'so' big and look 'just so' and produce a harvest of 'that much' that looks (and tastes) that good. A magazine photograph will do just fine. Then compare what you grow, with the 'model' somebody else grew (that a magazine considered befits the term: thriving) - and adjust as needed.

In shorter case, testing the base soil for AVAILABLE plant nutrition (NOT total nutrition) is also very important, along WITH specific site analysis for drainage characteristics. In many cases, raise-bed plantings with prepared dirt is the best option.

If so, the 'recipe' of dirt to use in such situation makes all the difference, and noting how to best TRANSITION dirt from a prepared mix INTO the natural soil, for best acclimation of roots down below...

Just hauling in 'fill dirt' can result in a DISASTER for intended plantings, both for amending soil AND raised-bed (or container) plantings. And purchasing a load of 'dirt' in plastic bags full of 'dead dirt' can be just as disasterous - a waste, unless the contents of the bag are properly labeled (which most are not) and a transition zone is prepared into the natural soil beneath.

And another topic that needs to be addressed (found in other sections) is the matter of preparing an 'artificial' mix with high organic matter content.

  • where does one find locally-produced high-organic content organic matter;
  • what does the mixing process consist of;
  • how does one tell if the organic material has a high content of microbial diversity;
  • what should a label on a bag contain,
  • what does the label information mean, and
  • what proportions of what, should be mixed together to provide a certain kind of result,
  • based on what criteria?

Yeah, you may have a few things to learn yet...

All things considered, replacement of soil may be the best option, for which double-digging or triple-digging is the standard practice recommended. If the area for designated soil replacement is large, renting some light 'heavy equipment' may be advisable (as easy to operate as your riding yard mower). Depends on the plants in the site-specific design and how they will be managed.

Vegetable garden standards for vegetable beds change with cycles of information published. The ROI standard for traditional in-ground planting bed dimensions for vegetables is 36" to 48" wide and as long as you have room for. Mounded or raised-bed, but dirt depth is dependent upon (1)bed design, and (2)the type of transition into whatever the natural soil base is. In any case, mounded beds mulched on top with grass clippings or hay or leaves (not wood chips) are recommended, and providing a growing medium in the bed that meets Soil Food Web standards to the full depth of root zone. Every plot of base soil is different, so a 'Jar Test' is recommended, and you are encouraged to use the Contact link to ask questions if you have some.

In any healthy soil or prepared dirt, a diversity of microorganisms must be active, due to a sufficient volume of aged organic matter being present, which offers a balance of plant nutrition in organic matter in sufficient quantity (depth) to SUSTAIN plantings without any future fertilization necessary (other than some compost tea now'n then - to ensure that microbe diversity remains high).

When amending soil that contains EXISTING plantings, the primary requisite is still the diversity of microbes based on the content percentage (and age of) organic matter available to root zones. If you haven't figured out yet how/where/for how much, to purchase high-quality locally-raised finished compost, then that's another reason you should use the Contact link. It's all about reading the packaging label. And if the information you seek is not there - don't buy the product. Buyer beware.

Compost tea is highly recommended, BUT if your plants are growing poorly in very sandy soil that contains less than 1% of organic material, and you apply a drench of highly-active and nutritive compost tea - chances are that the effort and expense will be wasted - simply because of the lack of sufficient organic matter in the soil or dirt to sustain the microbe populations - which can perish or leach down below root zones - unless sufficient organic content is present first - or added with the microbes.

Even if microbially-active high-humus compost is top-dressed around plants (on the surface of the root zone), such a compost tea drench would still be a wasted unless/until such organic matter has had time to 'work down' into at least the "feeder" root zone.

So the general standard is the determine/estimate the percentage of organic matter (OM) available to the plant at the ROOT zone. There are many methods to increase such percentage, and until there's at least 3% content, the dirt doesn't even rate as Skinny Dirt (much less Fat Dirt at 7+%), which is what it takes to establish a sustainable garden bed.

But y'know what gets me? Broadcasting 15-15-15, (one of the more popular synthetic fertilizers in average communities), gets more promotion from local Master Gardeners than somebody going to the trouble to amend their dirt with a load of 4-4-4 high-grade aged compost. It would be nice if Extension Service Master Gardeners at least provided their communities with appropriate treatment information for organic options.

Some sources recommend amending with up to 6 yards of compost incorporated into 1,000 square feet initially, and then in other places in the same information source, compost is limited to 2" thick as a top dressing because too much phosphorous might leach into water supplies. Go figure...Hmmmmph.

The ROI standard is, compost for amending soil or garden dirt needs to be finished and aged for a total of 6 months from initial build, before the microbe populations can be counted on, to provide a sustainable amount of plant nutrients to mature (bearing) garden vegetable plants.

If compost less than 6 months old (from initial build, with a minumum of two complete turns) is used for the FIRST time to amend a new garden bed, then at least ONE side-dressing of an organic fertilizer supplement at one cup per 25' of row should be expected at inital bloom-set. Why? Because the microbe diversity of the new compost in new garden dirt is 'immature' for sustainability purposes. It takes a bit of time for new compost to generate a sufficient level of plant nutrition from new organic material

Often have talked to homeowners who began composting in earnest, to start a new garden bed, then were disappointed with results - and tried various 'remedies' - who thought that such 'remedies' were probably responsible for good results after a season or two of garden bed production.

OK - let's deal with specifics - but in this, you only have three options. Read a label to find out if this information is printed - or send a sample into a laboratory to find out if it's any good - or buy a light microscope and learn how to use it.

This informtion pertains to COMPOST - not dirt. And there is NO natural SOIL that contains microbe diversity such as described in this standard. Does not happen.

Aerobic Finished / Mature Compost
Should contain a minimum of 100 million (108) to 10 billion (1010) Colony Forming Units per gram of dry weight material (CFU/gdw). Compost with less than 100 million CFU/gdw will not perform well as soil inocculant, to suppress plant disease or produce plant-available nutrition.

  • Aerobic microbes should be at least ten times greater in CFU than anaerobic microbes. Less than a 10:1 ratio indicates that sufficient gas exchange (CO2 to O2) was not accomplished in the compost material (e.g., the compost was not turned / screened sufficiently). Anaerobes and their by-products should be sufficiently degraded prior to using the material with plants, and should not be used to germinate seeds.
  • Fungi (including yeasts and molds) should be at least one thousand (103) but no greater than one hundred thousand (105) per Colony Forming Units per gram of dry weight material (CFU/gdw). Fungal units are important for decomposing recalcitrant organic fibers (cellulose / lignin) and compounds, soil nutrient cycling, aggregate stabilization and controlling certain plant diseases.
  • Actinomycetes (actinobacteria) populations should number at least one million (106) and up to 100 million (108) Colony Forming Units per gram of dry weight material (CFU/gdw). Actinobacteria are important in degradation of cellulose/lignin material and other complex organic substances (such as chitin - for treatment against root-knot nematodes), improve aggregation, and assist in reducing plant pathogen pressure. Actinomycetes prefer a more alkaline environment than other bacteria and are more prevalent after initial thermophilic activity has subsided.

Plant nutrition from organic matter by microbes

In northern climates, microbes in upper areas of soil 'go dormant' during very cold weather, so having only two-season vegetable plantings in northern climates does NOT mean that more nutrients are being made from the organic matter in the soil during winter weather just because plants are not utilizing the nutrients in the soil for the cold seasons. Depends on the depth that dirt is frozen, and duration of such cold weather, and dirt moisture content.

Changing organic material - into organic matter - then into plant nutrients, is not an over-night thing initially. However, once a sufficient content of organic matter exists in the dirt, NO additional fertilizers should be necessary, and nutrient delivery IS an 'over-night' thing. Proper nutrient 'balance' is also an 'automatic' thing with Mother Nature.

Remember that measuring 'total nutrients in organic matter is not the applicable measurement. Measuring AVAILABLE (to plants) nutrient is the applicable standard of measurement. On a lab analysis of plant nutrients, ask: Is the measurement provided, the TOTAL nutrient available - or IMMEDIATE nutrient available to plants? Nutrition that will be available later, does 'not count to plants - now.

Toxic Substances in Dirt

Many substances occur naturally in soil such as minerals, metals and some non-metal ions, eighteen of which are considered necessary for plant life and about half of those are needed in only tiny amounts called micro-nutrients or 'trace' elements. And, in excessive amounts some such elements can become toxic to plants such as copper and zinc. Other elements incorporated into dirt by man, such as mercury, lead, and cadmium can adversely affect plant life too.

Other toxic elements that man intentionally buries in the ground includes a host of substances toxic to both man and plant. Additionally man has become obsessed with use of synthetic fertilizers, herbicides and pesticides that find their way into dirt directly into water resources, by means of ground-level runoff, or underground water movement, where they tend to persist - and the only remedy is an abundance of microbial life that can - over time - detoxify or decompose the substances.

While most readers of this site will not have to contend with such issues in on their individual property, the standard is: don't bury ' ' 'anything that could potentially be harmful to plants, animals or leach into waterways. No paint, oil, metals (such as batteries) or plastics - and broken glass is not a good idea either. Dispose of all non-organic wastes properly, and compost all organic wastes. If it was alive and is now dead - and you are an experienced composter - compost it'''.

You might want to operate a separate 'critter' pile for "unusual" organic materials (such as road kill), then through the turning/screening process, remove "bulky" items back into the 'critter' pile. My critter pile screened matter goes into building new "regular" compost piles - then I don't have to be concerned with any finished compost that goes into garden beds. An alternative would be to just put 'critter' pile finished compost on ornamental beds.

Compost microbes are renowned for being able to mediate chemical waste - pesticides (including herbicides) included. There are however, two herbicides released that are difficult for microbes to mediate, but still they do - just takes more time...
In the past, organic farmers and land care professionals have not had to be too concerned about pesticide/herbicide residues in compost, because almost all such materials break down rapidly in the composting process.

Only recently has the 'almost' been added. The persistent herbicides: clopyralid and picloram, which break down more slowly in composting, have been found to be troublesome for commercial composters who 'push' their product, and so far, only sensitive plants have shown any sign of such persistence.

As a result, the primary clopyralid product, “Confront”, is no longer registered for commercial use on residential lawns. Nobody can purchase any of these without a license, so the only possibility of an issue, would be from a licensed commercial company using it on commercial lawns, golf courses and perhaps in the agricultural community on cereals, hay and pasture... But not likely. Even though the chemicals have been known to persist through the gut of a horse and cow.

If you have interest in them, check out these links:
http://www.mindfully.org/Pesticide/Clopyralid-Composting-Dow.htm
and
[[http://www.puyallup.wsu.edu/soilmgmt/Clopyralid.htm.

You might also check the article at: http://www.jgpress.com/BCArticles/2001/070132.html.

Your local county Agricultural Extension Agent should be able to tell you whether those products have been purchased and/or used within your community...IF he/she will? You get a nearby farmer or rancher to ask the Agent - to find out - which might motivate them just a little bit more than just a 'concerned citizen' asking?

So as a standard - do ALL pesticides and herbicided break down in compost? YES. Just making you aware that two particular new products take a bit longer, but it's not likely you'll ever encounter either of them in any compost feedstock.

Also be aware that the pesticide itself is not the entire story - they have "degradation pathways" during breakdownm which should not automatically be considered biologically benign. 2,4-dichlorophenoxyacetic acid (2,4-D) produces 2,4-dichlorophenol as its initial degradation product, and this halogenated aromatic compound is SIGNIFICANTLY more toxic than the parent herbicide. Interesting, but not much to worry about. Not many users of 2,4-D around nowadays. But the main point is, this degrading issue (pun intended) may become more of a future concern, as chemical companies compete for a larger "market share" at the expense of the purchaser...
This is exactly what I mean about 'trashing' our planet because of greed and no thought about what future generations are going to have to contend with.

One more word about contaminants: sewage sludge (biosolids) is still on the ROI list of no-no's. Yes, there's Milorganite, Dillo Dirt, Texas Super Dirt and a host of others, as USDA licensed commercially-composted sludge products. What does that tell you about commercial compost in bags at the 'big box' store? Yup - they'll sell anything that the public is gullible enough to spend money on, that is not proven to be a human health hazard (yet). It's still the uncontrolled (aeration/water) issues during the commercial composting process that raise ROI concern, due to the lack of microbe diversity to mediate the process. AND lack of adequate direct method (microscopic) laboratory testing to determine that a diversity of beneficial microbes exists in it. Hey - don't take my word for it - READ THE LABEL for what's NOT THERE...

The products noted above, appear biologically 'dead' through my microscope. Maybe I just got some "bad bags"? Hmmm, find and send me a sample of some 'live' stuff. Compost tea from any of them 'sucks' too, biologically and nutritionally.

This author would not even consider trialing Dillo Dirt after checking out several bags with my microscope, but did purchase several yards of bulk Texas Super Dirt to trial. Still have a lot left - won't even give it away, 'as is' - now experimenting with using it as a compost feedstock to try and find a way to get it into the ground to do some good. Way too expensive for what's NOT there.

SOIL FOOD WEB

The total community of microorganisms (microbes) living in organic matter, along with a host of tiny creatures called 'decomposers' are considered the Soil Food Web. Nature determines what the microbe population diversity should be, and maintains them based on the amount of organic material and organic matter (microbe food) available in the root zone of a plant - regardless of whether the plant is in native ground or in a prepared-media raised bed, or even in a container. Basically, the microbes that live in the organic material/matter don't care where they are, as long as they have sufficient food, air, favorable temperature and moisture.

In natural soil systems, organic matter generally cycles in location, added to the soil through root and stem decay of winter-killed annuals and leaf decay.

IF a sufficient supply of organic material is available, a thriving microbial ground-level community digests and breaks it down into organic matter, to eventually release nutrients back to the soil. However, that's a very big IF.

Typically a native soil will contain less than 1% organic matter, unless a significant number of trees or shrubs are providing leaf-fall, or a high self-seeding population of annual plants exists.

Best-case scenario is accomplished by composting and/or direct mulching with fast-decomposing organic materials. By closing the nutrient cycle in this way, the need for external inputs is minimized - with the exception of lawn turfgrass, which has extraordinary nutrient needs because it is grown in an unnatural way –– perpetually mowed and kept green as long as possible. Maintaining a lawn is such a huge water-waster.

For turf, extensive organic top dressing may be needed to help balance the dirt's chemistry, stimulate its biology, and maintain or restore the physical composition - something a synthetic fertilizer cannot do, and in fact, man-made chemical fertilizers contribute to a large amount of turf problems.

On the other hand, organic matter amendments to the soil may be needed - moving nutrition and microbe populations down INTO the base soil - which changes it into dirt, because the natural composition has then been altered forever. A good thing, expecially for turfgrass thatch buildup.
It is a rare thing indeed, for turf grass to be growing on unaltered soil. Where humans build and live, soil quickly becomes dirt.

Synthetic mineral fertilizers should not be used to artificially stimulate any plant growth. Unnecessary applications of any synthetic fertilizer or in an organic soil amendment can cause mineral nutrients to build up to excessive levels, causing pollution by entering water resources.
Nitrogen and phosphorus are the main nutrients most involved in eutrophication of water bodies, and nitrogen can become a health hazard by polluting well water drinking supplies.

Most potential nutrients in soils are not readily available to plants, being 'bound up' for one reason or another, until microbe populations change them into a form that plants can uptake, which depends on multiple site-specific environmental factors that depend on good stewardship of land.

While amending soil to become dirt is a common practice, and quite beneficial, factors of erosion and initial disturbance of the native microbe populations should always be considered, as well as using renewable organic amendments that are sustainably produced (such as using Canadian sphagnum peat instead of mountain peat - that cannot be renewed in a hundred years). We do not want to waste resources for our short-term benefit.

Organic soil fertility is based on feeding the land, not just the plant. This means that carbon is fed along with nitrogen through the use of manures, compost, organic mulches, blended organic fertilizers, and growing nitrogen-fixing cover crops is very beneficial, as is rotating crops.

Artificial horticultural methods which short-cut this natural order by directly feeding plants synthetic (so-called "balanced") nitrogen-phosphorus-potassium (NPK) fertilizers, leads to damaged microbe populations and weak root systems, making the plants more susceptible to insects, disease, and drought.

Over-fertilizing any plant (chemically or organically) may also inhibit the development of mycorrhizae—symbiotic fungi growing on and around plant roots that help to gather nutrients beyond the range of the roots themselves.
By constantly adding synthetic fertilizers, eventually the biological system collapses and it becomes infertile. To revive dead, compacted dirt, it may be necessary to apply compost as an amendment, to improve and re-build life into that part of the land.

A well-balanced program for plants to grow in the ground or in raised beds, that increases organic matter content, provides many other benefits too, such an organics program recycles nutrients, improves water retention, balances minerals, and buffers pH.

In addition to compost and aged manures, other dirt components may be indicated based on test results, such as root stimulants, rock dust, secondary micronutrients, flocculents, conditioners, and a host of organic supplements (such as kelp meal and cottonseed meal), and compost tea, which includes beneficial microbes, organic humic substances, fulvic acid and more.

For portable containers (pots), the normal stepping-up procedure (to larger containers, as root mass increases to fill the existing container) provides opportunty to increase organic matter et.al., in the new dirt around the root ball, and change the medium formulation to accommodate changes in the plant maturation process.

CATION EXCHANGE CAPACITY (CEC)

Most turf grasses and ornamentals grow best when certain cations are in balance, with base saturation in these ranges: Potassium 2-7%; Calcium 65-85%; Magnesium 10-20%; Hydrogen 0-5%; Sodium 0-5%. Micronutrient needs may differ according to the turf or ornamental plant type, and certainly pH of the growing medium is important.

Vegetable plants are in a class to themselves, and while CEC is important, in a normal environment prepared for growing vegetables, sufficient care is usually taken by attentive gardeners to provide abundant organic material, which becomes organic matter, which is then processed into a balanced environment by microbe populations.
So the CEC standard in both cases is to ensure that a sufficient volume of organic matter is available to plant roots in a balanced air/moisture environment.

pH (percent Hydrogen)

It is important to get the pH of any planting medium in the right range, whether in the ground or as a growing medium (dirt).

Knowing whether a certain plant prefers an acidic or near-neutral medium is the key.

ROI standards also consider importance to balance the calcium-to-magnesium ratio in dirt.

Not many terrestrial plants prefer an alkaline growing environment - but for the few that do, if the dirt is already high in magnesium, use calcitic lime instead of dolomitic lime (which is high in magnesium).

Adding elemental dusting sulfur is the recommended method to lower pH (more acidic), and lime to raise pH (more alkaline).

One of the most frequent mistakes that people use to injure plants is watering plants - that prefer an acidic growing environment - with alkaline water. Do you know the pH of your tap water?

Especially when raising plants from seeds - test the pH of the water. Sure, you may be using a 'sterile' seed mix, but if the environment is alkaline due to water, seeds will not get the best start, and a high a pH can deform or kill young seedlings by preventing uptake of nutrients.

TESTING

Testing is important. Testing is necessary to determine what kind of soil or dirt plants are being (or will be) grown in.

Land grant universities offer soil test laboratory analysis through county Extension Service Agents and some of those Service Agents oversee a Master Gardener organization that can provide limited information. Each state in the U.S.of A. differs extensively in the information they provide, and county Extension Service offices differ within states, and advice from Master Gardeners differs on an individual office basis. So the standard is: Consider the source and don't believe everything you are told, even in writing - and that applies to this site information too. Verify the information as relative to your specific project, before you act on it.

The standard is: Check it out for yourself, to learn what the site-specific needs are of the plants you grow - or intend to grow. Don't take somebody else's word. Decisions are YOUR personal responsiblity and nobody else's. Verify before you act.

This author recommends double-blind testing on the soil or dirt you intend to plant in. Yes that means double expense, and if you cannot afford two tests, you probably shouldn't afford to do one.

Point is, that in this author's opinion, private testing laboratories do a MUCH better (more complete) job (and provide more information) than any state land grant university will. BUT being a Master Gardener, supporting the AgriLife Extension Service in the state in which I reside, I have agreed that the first test should be through your county Extension Service - on the theory that soil in your state is different than some other state. But the only thing that matters is the growing media you test in your local environment - which has NOTHING to do with the other soils/dirts in the rest of the state. So there.

That's why I recommend testing twice, by two different sources. Then you have the information needed to make decisions about what lab does your testing from then on. The land grant university lab costs will be a bit less than a private lab - but you get what you pay for. Try going back to the land grant university soil laboratory about questions regarding your soil test. What you'll get is a 'standard reply' that basically tells you nothing about your specific analysis results. Private labs at least address individual inquiries more aptly.

Why is that? Land grant university soil testing laboratories are 'geared' toward commerical agricultural operators - which is what county Agricultural Agents are focused on at the state level too - although there are some really good Agents 'out there' that do benefit their local residential community, and every now and then - you might find one that actually knows something about organic gardening. But not very often.

And there are some tests you should learn how to do yourself, on a fairly regular basis, because if you garden organically, it is a dynamic enviroment - always changing as plantings come and go seasonally.
Test your garden dirt seasonally with your own preferred testing method(s) before making new plantings, if you have amended the dirt since testing it last season. Don't guess.

There are some very good "self-test" kits 'out there' on the market. You'll need to search the Internet to find reliable ones, and the main thing to remember about ANY self-test - is that you have to learn how to perform it consistently.
Consistent methodology is the key - no matter what brand of test you choose. Follow instructions explicitly.
If you make compost tea from your compost pile (which you should), test pH with litmus paper, in addition to an electronic meter. Most electronic meters are not made to test straight liquids. Have the compost tea tested for microbe density and diversity at least once a year.

The ROI laboratory tests both physical compost and compost tea for population density and diversity. Click on the ROI Testing Laboratory? link for more information.

  • pH:

A high-quality electronic pH meter is a good investment. This author recommends the Luster Leaf 'Rapitest' product as the lesser price point, and the the Hanna pHep5 at the upper price point.
Why? Because the Luster Leaf pH meter is only pre-calibrated against a standard buffer solution and the Hanna is capable of two-point calibrations against standard buffer solutions that you can prepare, to check calibration. In the hands of a trained soil tester, Hanna readings are precicely accurate.

The pH of soil or dirt is measured by preparing a SLURRY of the sample in distilled or deionized water, swirling the THICK suspension for a minute or more, then placing the meter in the semi-liquefied (just enough water to get a good mix) sample until a stable reading is obtained - about 30-60 seconds. Follow directions for use - do not scrub the tip of the meter with a scouring-type pad.

  • Moisture:

An electronic moisture meter is a good investment, and this author recommends the Reo Temp product only, because it has a long enough (18"+) probe to actually get far enough down into soil, or dirt, or in a large container to test the base of roots. It is not cheap at $50+, but it is built rugged and the strong handles are durable, to withstand the force of getting the single probe tip down where it needs to go. And it can be calibrated against a standard sample, with a small screw driver.

Over-watering is usually more damaging to plants than under-watering (yes, depends on the plant. Whatever regimen, regular watering is best and irregular watering is worst).

One of this author's major gripes is that the greenhouse growing industry uses a potting medium that is so coarse - to withstand constant water/nutrient-feeding - that when a buyer gets a containerized plant home without benefit from such an artificial watering environment, that the plant is likely to die from irregular watering, before it can be properly hardened-up and/or planted. Plants that have been treated to daily watering in a nursery environment should be bottom-watered with a tray or saucer. Transplant shock takes its toll too, to only transplant when the potted plant AND the planting hole have been watered well. A 'transition' time is needed for any recent transplant to acclimate...

This author's advise to persons intending to purchase greenhouse-grown plants from commericial 'big-box' stores is: Don't make the purchase until the planting hole is dug and pre-watered, then get it planted within 8 hours of the purchase. Then if the plant dies, you can return it for a refund or replacement in good conscience. The greenhouse industry counts on a low percentage of returns to attain their net profits.

  • Temperature:

Relative primarily to composting, which requires a high quality thermometer with at least a 20" probe, and again this author recommends a 20" Reo Temp product because of durability - but keep the tip clean, and use two thermometers, to ensure accuracy of readings - because accuracy is very important.
These instruments do not last 'forever', and you should not be without at least one, should the other one fail. If a compost thermometer is available, use it during the summer to determine the effectiveness of mulch around plants to keep the ground cool several inches below the surface. Also use it to check the temperature of roots in potted plants in direct sun. More mulch to keep containers cool might be appropriate.

  • Plant nutrition:

Is sufficiently important to recommend as a standard test at least once each year for bedded plants, particularly vegetable gardens. There are some tests for plant nutrition sold at local 'big box' stores - that are not worth the powder to blow them up. Do your 'homework'. Buyer beware.

On the other hand, there are some very good tests for plant nutrition in dirt. As with any test, consistency in the method of taking and applying the test is the most important issue. Since nutrition in organic matter is a matter of microbial activity, directly related to air and moisture content of the sample, nutrition of dirt is usually going to be a laboratory function relating to determination of the microbial density and diversity of the dirt.

You can certainly learn how to determine microbe density and diversity, but that requires a microscope in the $1,500 range and some specialized training, particularly to analyze compost tea, which is the 'mirror image' of physical compost. The ROI Testing Laboratory is available to test your samples - check out the ROI Testing Laboratory? link in the left sidebar.

In this author's opinion, if a gardener makes good compost and brews good tea from his/her compost, peace of mind should reign, that no other source of plant nutrition is needed, or any other product to treat plant diseases, or even plant pests (save an infestation from a wayward neighboring property).

Health of soil or dirt is a microbial function. To the degree a planting medium has sufficient organic matter (food) and clean water and air to maintain healthy microbe populations, a gardener can trust Mother Nature to 'do her thing' appropriately within the context of "right plant, right time, right place" - and other human intervention issues.

Organic content of dirt

The only relative question: Is there enough? There's only one way to find out - test for it. Can there be too much? This author's opinion is no - and if you think so, then "too much" is still better than too little - but the 'jury' is still 'out' on that issue.

This author has grown a LOT of plants in straight 100% aged compost. And watered them with concentrated compost tea. For example, papaya trees 12' tall in 20-gallon containers with only compost, that bear delicious football-size fruit.

If you plant in that heavy of an organic matter content medium, and water extensively, you should consider using a mild organic fungicide that will not damage very important mycorrhizae fungi. See: http://www.mycorrhiza.com/index.php?cid=396

Endo fungi are most common to 95% of the world's plants, whereas Ecto fungi are only common to confifer trees. Currently this author has many other kinds of trees growing in pure finished compost as experiments. Pecan, Redbud, Elm, Cottonwood, Mimosa, just to name a few. The main issue with doing that is drainage which means either using containers with side-draining holes, or elevating the pots. Some plants just don't like their roots that wet, on a continuous basis. Learn to mix your own planting media.

With water-loving Sycamore and Bald Cypress trees, I use huge (home-made) saucers to maintain continuous moisture in the compost (using foam pipe insulation, sheet plastic and duct tape). Other trees have saucers and some don't. After 3 years of trials, it appears that most trees rooted in almost pure compost prefer full drainage, but most will tolerate 60% moisture for long periods.

Most of the trees and shrubs I trial in 20-gallon containers are planted in various dirt mixes using ramial wood, coarse river sand and other components.

Many plants can handle a lot of moisture for quite awhile, but most like to have the dirt dry out to about 25% moinsture between waterings.

So the standard is: Depends. Use your own judgement and measure water content. Record results to track progress.

COMPOST

Compost feedstock standards: For compost and compost tea that is balanced between bacteria and fungi (but can be slightly higher in bacteria depending on moisture content), the following feedstock proportion is standard:

  • 25% animal manure (or worm castings), 50% green material (household table/kitchen scraps, green leaves, cured hay and fresh grass clippings), and 25% ramial wood (twigs less than 7mm), or finely-shredded brown fallen tree/shrub leaves, softwood bark (such as loblolly pine) and/or mushroom substrates). Softwood or hardwood sawdust can be used, but be very careful not to use too much - sawdust can easily be in the 500:1 range...

For a compost higher in fungi (needs a moisture content in at least the 40% to 50% range) the following feedstock proportion is standard:

  • 50% green (nitrogen-laden) material, 50% (high-carbon) materials resistant to rapid decay. The green material should include at least 5% fresh manure or worm castings.

Calculating C:N

Is difficult in the field, because estimations rely on volume (not weight) of raw organic materials of an undetermined age (weathering).

How long an organic material has aged, in what kind of weather, has a lot to do with what the C:N ratio of a given feedstock actually is, which may be quite different from the C:N ratio for a 'named' product given on a sheet of paper - that lists a variety of 'average' potential feedstock from an unknown area of the country.

For example, the C:N ratio of live oak leaves and their durability under aerobic composting methods, acidity and what kind of microbes they feed - is VASTLY different from quaking aspen leaves or pine needles or southern pecan leaves under the same decomposition conditions such as temperature, rainfall, moisture, etc.

The ONLY way to know for sure, is to get a laboratory C:N analysis of what you consider to be an 'average' age feedstock that is common to your area (a consistently available product) that you can guage adjusted C:N from in the future. In lieu of laboratory verification, the best you can do is rely on your experience and the experience of other composters in your local area, using the same feedstocks. If you don't know how to find local composters, you should use the Contact link and find out.

Also, layering or mixing a quantity of one feedstock with another to build a compost pile - to arrive at an overall C:N ratio is another interesting challenge in the field. Notwithstanding, it can be, and often is, accomplished by experienced composters who process the same feedstocks over and over and have been able to 'get a handle' on how the various organic materials react to microbial activity in a variety of different environmental situations - the way that THEY do it.

People that know these things and are able to produce a consistent product are composting EXPERTS, and their skill has absolutely nothing with how old they are, or how many books they have or have not read, or any other "criteria".

Those folks should be training other people to do what they have learned to do. If you, or anyone you know, is able to do that kind of thing - no matter HOW they compost - ORG would like to investigate certifying them as composting experts so somebody is more likely to take heed to what they have to say. America needs to hear from those folks. And learn a thing or two from them. Even if they still check pile temperature with an old piece of rebar.

Some composting standards involve whether organic material has become stable, mature, finished or aged. Laboratory testing is advisable, but is not always practical using the fast, hot aerobic batch method, by a ORG certified composter.

  • Appearance: should be dark, with a crumbly/porous texture and a pleasant 'earthy' aroma.
  • Pile material should have attained 131F twice: once after initial build, and again after the first turn with scalped material internal to the new pile.
  • Moisture level between 40% to 60%, but this is not a restrictive standard with aged material over 6 months old that will be harvested soon.
  • C:N ratio: should be between 20:1 to 35:1 but this is not a restrictive standard with aged material over 6 months old.
  • pH should be between 6.5 and 7.2 but this is not a restrictive standard with aged material over 6 months old.
  • If organic matter is less than 2 months old, temperature of the center core is indicative of material stability.
  • If pile material has been processed through two turns within 8 weeks (60 days) from initial pile build, and the core is below 100F, material is considered to be STABLE.

If organic matter is less than 6 months old, there are some simple tests that should be standard for certified composters before a pile is harvested. Note: for these tests, pile material should contain a minimum of 40% moisture. Light misting with a spray bottle is acceptable practice BEFORE sowing seed.

  • (1) place two cups of composted organic matter in a quart plastic bag and remove most air by rolling it up from the bottom (but do NOT compress the compost), sealing the plastic bag tightly, then unroll it, letting it set out in a shady place for no less than 24 hours at room temperature.
    • If the sealed quart bag expands to or greater than 'semi-tight' fullness, with gas content any greater than the area of solid matter, the compost is considered NOT stable. Turn/re-aerate and let it compost for another 3-4 weeks.
    • If the sealed quart bag does not expand (by gasses produced) beyond the total area of solid matter, the compost is considered to be STABLE.
  • (2) Place two cups of well-moistened compost in a quart plastic bag and fold down the top of the bag to the outside, so it will remain open.
    • Sow 1/4 teaspoon of Watercress (Nasturtium officinale) seed on top of the two cups of compost in the plastic bag (approximately 25 seeds).
    • Cover the Watercress seeds with one cup of compost, leaving the bag open. The top cup of compost may be finger-spread and slightly tamped and misted if desired.
    • If the majority of Watercress seeds do NOT germinate after 5 days, or are spindly/weak/twisted, then the compost is NOT finished.
    • If the majority of Watercress seeds germinate within 5 days, are over 1" tall and after 7 days and appear healthy, the compost is considered to be FINISHED.
  • (3) Place two cups of well-moistened compost in a quart plastic bag and fold down the top of the bag to the outside so it will remain open.
    • Sow 1/8 teaspoon of Red Clover (Trifolium pratense) seed on top of the two cups of compost in the plastic bag (approximately 25 seeds).
    • Cover the Red Clover seeds with one cup of compost, leaving the bag open. The top cup of compost may be finger-spread and slightly tamped and misted if desired.
    • If the majority of Red Clover seeds do NOT germinate after 5 days, or are spindly/weak/twisted, then the compost is NOT mature.
    • If the majority of Red Clover seeds germinate within 5 days, and are over 2" tall after 9 days and appear healthy, the compost is considered to be MATURE.

The standard for Expert composters: If it was alive and is now dead (or recently harvested or excreted) compost it. Aerobically or anaerobically. If you don't want to see bones in your pile anymore, take them out when you turn/screen the pile - and bury them But they will compost eventually.

The standard for Experienced but Non-Expert composters: Compost to the level of your experience, but 'push the envelope' to learn more.

The standard for Beginning composters: Stick to the basic aerobic feedstock formulas until you gain confidence in your composting skills. Then try composting the full variety of feedstocks available in your area (that are free).

The standard size of a compost pile in order to establish thermophilic biomass (compression) is one cubic yard (3' x 3' x 3') with height of material being the most important dimension.

The standard method of aerobic composting is a pile with as close to vertical sides as is physically possible. A containment method may be employed if desired.

The standard timing for turning an aerobic compost pile is at least every 4 weeks. Sooner is better, but not more often than 2 weeks. If a compost thermometer is available, the compost pile should attain a minimum of 131F within 9 days of initial build, and maintain that minimum temperature for at least 3 days. After the first aerating turn of pile material (using the 'scalping' technique), temperature should reestablish to 131F for a minimum of 3 days. Heat-producing amendments are permitted in the initial pile build and with first turn. After 2nd heat, no additonal organic materials should be added if using the Batch method.

If using the Continuous-Add method, compost should be aerobically screened and permitted to 'rest' (age) for at least 90 days (with no additional organic material added) before being used in a vegetable garden.

Many folks live out in the country and don't have the convenience of community trash pickup. Most country folks learn to recycle/reuse/compost early-on. Try hard not to send anything to the landfill except metal, glass and plastic. Compost the rest.

Even apartment dwellers can compost - talk to the maintenance folks who take care of the grounds. Some of them may compost or know somebody who does. Apartment buildings maintain ornamental plants, which is expensive. Composting for the complex is smart. Ask neighbors about starting a compost pile, or a vegetable garden, to cut costs.

While aerobic composting is by far the most popular method, anaerobic composting is an acceptable method of making planting dirt for wetlands plants.

On the other hand, when applying methods for aerobic composting, if anaerobic conditions are encountered, quality control measures need to be addressed.

Standard for moisture content of compost should not exceed 60%, but in most cases using aerobic methods with adequate drainage, anaerobic conditions will not be encountered until over 75% moisture content is exceeded. However at excessively high moisture conditions, decomposition may be retarded somewhat, depending on the diversity of microbes being grown.

Compost Tea

For compost tea standards, this author defers to Dr. Elaine Ingham, PhD of http://www.soilfoodweb.com and
http://www.sustainablestudies.org. However, consider these points:

  • Compost tea is used to adjust soil biology, and is effective, to the degree that a percentage of organic material exists in the dirt, to feed microbe populations.

Without sufficient organic matter "food", microbes in dirt may perish or 'go dormant'. An environment for microbe reproduction is key. Again, remember that a microbe life cycle is measured in MINUTES, not hours.

  • ORG recommends using compost tea in whatever form it is available, whether leached or brewed.
  • Compost tea is a (dirt) product of natural elements, found in nature, that has been known to:
    • aid in deterring plant diseases
    • aid in deterring plant pests
    • provide immediately-available and balanced organic nutrition to plants from microbial activity
    • provide some micronutrients in immediately available form, to plants
    • provide microbes that assist in the chelation of some needed trace minerals and metals
    • enhance or restore soil and leaf surface microflora when used as a foliar spray (use a wetting agent for best results)

Also important to remember that under current laws, commercial compost tea products cannot claim that the product suppresses or controls plant diseases or pests, unless the product is registered as a pesticide (disease also being a pest) by the U.S. Environmental Protection Agency.

And remember that resultant tea microflora is only going to be as good as the compost was - from which the tea is derived.
Said another way: The quality of compost tea is dependent on the quality of the compost used to make it.

Brewers of compost tea should adhere to the microbe food recipe recommendations of any mechanical brewing equipment manufacturer, because much depends on how any given piece of mechanical/electronic equipment functions, especially in determination of brewing times, to acheive desired product results.

Besides liquid molasses as a primary carbon feedsource, other microbe foods may be added such as worm castings, kelp and/or fish hydrolysate, with yucca extract, saponin, rock dust, humic acid and/or fulvic acid added as catalysts to create specific-use teas.

Animal Manures

There are basically two kinds of land animals (earthworms excluded) from which manure is harvested for composting and tea-making:

  • omnivores (including carnivores such as dogs, cats and birds - and humans)
  • herbivores (principally, grass-grazing livestock)

Yes - pathogens exist. They will always exist. A normal amount of care will suffice to protect you and your plants. Experienced composters process manures from horse, cow, mule, burro, sheep, goat, hog, pig, poultry, cat, dog, etc., etc...
Oh, excuse me - is there a 'line' you want to draw? Why?
There is no need to get 'freaky' about the possibility of pathogens in pet poo. Follow physician's advice - wash hands after handling any poo.

As a standard, 131F compost temperature for 3+ hours kills pathogens. ALL of them. EVERY time. And 6 months of aerobic composting will too - WITHOUT heat.
Mother Nature's system kills pathogens over time, even without help from aerobic thermophilic heat. Mother Nature's system is trustworthy.

Composters learn to trust the microbes they raise, because they see organic materials 'disappear' into sweet-smelling organic matter.
This author looks at compost microbes often, through a very expensive microscope in a laboratory setting, and has learned to trust what they do.

This author is an Expert composter, so road kill gets composted, and assume they got killed because they were not paying attention - not because they were sick.
Some might have been sick - but it's a bit late to worry about that issue. But a separate compost critter pile "cures" sick dead roadkill too.
Compost all organic feedstocks to the degree your experience permits. And 'push the envelope' sometimes - to learn, when the opportunity presents.
If you have doubts, just put that particular batch of compost on your ornamentals and not on your garden.

If you have a pet, then you scoop poop or throw out the litter and just send it off to the landfill? - or do what with it?
You think it's better just to 'hide' it? Out of sight - out of mind, eh? That is NOT the best solution for organic, compostable materials.

Now the subject turns to using RAW manures for direct land care.
There is a difference between FRESH raw and AGED raw.
And there is a difference between using fresh/aged manure on the surface as top dressing, versus incorporated into the ground, as an amendment.

Top ground use, is a matter of exposure to above-ground critters, degree of anticipated weathering and microbial activity over time based on moisture.
Yes, both wild and domestic animals poop on top of the ground all the time (called scat). Mother Nature has dealt with that issue for millenia.
Point is that animal excrement decomposes better when incorporated into/with other organic material than it does exposed to weathering on the surface.

Either raw or aged manures of any type or kind may be amended into the ground and moistened appropriately to ensure that microbial activity takes place.

BUT - a significant quantity of fresh manure in any one place, can produce heat from thermophilic microbes, sufficient to kill plant roots, above or below ground.
Depends. On a lot of factors. Just so you know that's a possibility - if raw manure is not sufficiently distributed within a given area.

As a standard, fresh raw manure from any animal should either be incorporated into the ground, covered, or composted aerobically or anaerobically.
Animal manure that has aged and/or 'weathered' more than than six months may be mixed with planting media, fertilizer or used as an amendment.
Aged manures of any kind should be broken up and moistened before using, to assist in rapid decomposition. Water-soaking is a common practice.
Making a water-based slurry of aged manure before applying, with amendments as appropriate, is acceptable practice for surface application when mulched with grass clippings, hay/straw or shredded leaves or top-dressed with finished compost.

Raw Organic Material (not aged 'matter') as an Amendment

The practice of working-in raw organic materials into soil - makes it dirt, no longer soil, and such practce has been as popular (or perhaps moreso) as composting.

Leaves, grass clippings, hay, straw, ramial wood (less than 7mm diameter) and manures has been a standard feedstock mix since at least 450BC as attested by the highly microbiotic 'terra praeta' dirt pockets found in the Amazonian Basin in South America.

The advent of huge 'chippers' to make mulch out of tree trunks and branches in the last several decades has increased the practice of mulching - generally a good thing for covering the ground where surface plants are not desired - but such woody (high cellulose/lignin) material is NOT recommended as an in-ground amendment or as a compost feedstock.

The basic principle is: organic MATTER, with established microbiology density and diversity is MUCH more beneficial as an in-ground amendment than un-aged organic MATERIAL that has not begun long-term decomposition.

Burying organic materials can certainly assist with increasing the porosity (texture) of soil and therefore the drainage of dirt, as well as moisture and air retention - but decomposted (composted) organic matter will accomplish the same purposes MUCH faster (than raw organic material) and with much faster microbial results.

Organic material takes a LOT longer to decompose in the ground than it does in an aerobic compost pile. How long depends on conditions under the surface of the ground, but generally speaking, on average it may take up to a year longer in many cases - since under the surface, air necessary for microbes to be highly reproductive - is MUCH more limited than in a properly-managed aerobic compost pile.

If kitchen and table scraps are buried in the ground, an anaerobic, smelly, putrification condition can easily result, including messes from digging up of, and spreading of such material by ground-dwelling critters, especially dogs, racoons, possum, skumk and others.

Such practice of burying raw wastes in a community setting is highly frowned upon by county environmental health agencies who promote (and even sponsor) aerobic composting practices.
Yes, many organic gardeners practice the burying of organic materials in their garden beds, but in doing so, they take a chance on promoting the rapid growth of bacteria and fungus organisms that can be harmful to their vegetable plants.

Nitrogen

Nitrogen is an essential nutrient in the process of aerated compost decomposition.
Nitrogen is the most abundant gas in the atmosphere (78%) but gaseous nitrogen (N2) is inert and therefore unavailable for use by animals and most plants. Turning N2 into available nitrogen by “fixing” it, requires breaking the bond between nitrogen atoms, which requires energy.

Under natural conditions nitrogen is fixed by lightning strikes through the atmosphere and in soil, dirt and water - by certain bacteria and fungi (microbes et.al.). The amount of “fixed” nitrogen being produced at any given time in the world, is quite small compared to the amount already fixed and cycling through the ecosystem (see: Nitrogen Cycle).

Nitrogen is an essential macronutrient required to create amino acids and proteins, enable genetic material in animals, along with enabling chlorophyll and other important biochemical molecules in plants.

The amount of fixed nitrogen entering the cycle through the industrial (man-made/synthetic) production of fertilizer, selective cultivation of nitrogen-fixing plants and the burning of fossil fuels has increased dramatically world-wide in the last two decades.

It takes a LOT of energy to manufacture synthetic (inorganic) fertilizer from N2. Check this link for more information: http://www.epa.gov/watertrain/nitroabstr.html.
Hugely wasteful of energy, and causes pollution.

So-called "greenhouse gases" in the atmosphere have increased multi-fold in the last several decades, which are partly responsible for depletion of the protective (from UV) ozone layer, increased acid rain, air pollution (smog), eutrophic (over-productive) conditions in freshwater bodies, algae blooms and 'dead zones' in saltwater and changing ecosystem balances in many other ways.

Plant and animal nitrogen sources may also contain phosphorus, which can be detrimental to plants in soil and dirt when high quantities are present, while creating deficiencies in other nutrients (calcium, potassium and magnesium). Man-made nitrates leached into drinking water from wells have also been linked to human health problems.

Suggested organic nitrogen amendments:

  • mature compost
  • compost tea
  • blood meal
  • alfalfa meal, vegetable meal, feather meal
  • fish hydolyzate, emulsion or meal

Phosphorus

Phosphorus is an essential nutrient in the process of aerated compost decomposition.
Phosphorus, in the form of phosphate (PO4), is also an plant essential macronutrient and a vital part of the ATP system (plant cellular energy transfer) in plant photosynthesis (conversion of light energy into chemical energy) and is involved in the formation of all oils, sugars, starches, etc. Phosphorous also helps with proper plant maturation (flower and seed formation); withstanding stress, effects rapid plant growth and encourages root growth.

Phosphorous can be leached in water and carried to aquatic systems, so care should be exercised to control phosphorous levels in dirt. Rock phosphate dust from weathering is a source of phosphorous in natural systems. Man-made synthetic fertilizers high in Phosphorous have contributed greatly to increased phytoplankton and bacteria growth in downstream aquatic environments, causing loss of dissolved oxygen and loss of animal life (dead zones) in the ecosystem.

Suggested organic phosphorous amendments:

  • mature compost
  • compost tea
  • bone meal
  • alfalfa meal
  • rock phosphates
  • greensand (if supplementation of iron is also indicated)

Potassium

Potassium is an essential nutrient in the process of aerated compost decomposition.
Mineral source of potassium is mainly feldspar and mica.

Potassium is the only essential plant nutrient that is not a constituent of any plant part, but is a key nutrient in the plants tolerance to stresses such as cold/hot temperatures, drought, wear and pest problems.

Potassium acts as a catalyst for many of the enzymatic processes in the plant that are necessary for plant growth to take place. Another key role of potassium is the regulation of water use in the plant (osmoregulation) which affects water transport in the xylem, maintaining high daily cell turgor (pressure) which affects wear tolerance, affects cell elongation for growth and most importantly it regulates the opening and closing of the stomates which affect transpirational cooling and carbon dioxide uptake for photosynthesis.

Suggested organic potassium amendments:

  • mature compost
  • compost tea
  • Seaweed
  • alfalfa meal
  • rock or quarry dust
  • greensand (if supplementation of iron is also indicated)
  • sulfate of potash (potassium sulfate)
  • sulfate of potash, magnesium (such as sul-po-mag®)
  • clean wood ashes (raises pH - use with caution)

Calcium

Calcium is an alkaline material, thus keeping the soil pH higher if in abundance, and is relatively insoluable, so tends not to leach away.
Soil microbes need calcium too, consuming and converting calcium compounds into a form plants can use.

Plants need calcium for cell wall development and growth. Pathogens attack weak cell walls to invade a plant, and stronger cell wall structure avoids this. Plants need calcium for enzyme activity, metabolism, and for nitrate (a useable form of nitrogen) uptake. Calcium and phosphorus are often found together. Too much sodium in the soil can bind up calcium and make it unavailable to plants. Most forms of calcium are not readily available to plants and must be broken down by microbial activity.
Recommendation is to apply a SOFT rock phosphate. 'Soft rock' is a colloidal, more soluble natural source of phosphate and calcium.

Suggested organic calcium amendments:

  • Aragonite (crystalline form of calcium carbonate)
  • calcitic limestone (mineral form of calcium carbonate)
  • agricultural (finely powdered) gypsum (calcium sulfate)
  • soft rock phosphate (such as CalPhos)
  • kelp meal or Kelzyme®
  • dolomitic limestone

Sulfur

Sulfur is an essential element for growth and physiological functioning of plants, however - its content strongly varies between plant species and it ranges from 0.1 to 6% of the plants' dry weight. Sulfate taken up by the roots is the major sulfur source for growth, though it has to be reduced to sulfide before it is further metabolized.

Root plastids contain all sulfate reduction enzymes needed, however - the reduction of sulfate to sulfide and its subsequent incorporation into cysteine predominantly takes place in the shoot, in the chloroplast. Sulfur deficiency will result in the loss of plant production, fitness and resistance to environmental stress and pests.
Elemental (soluable-dusting) sulfur is the primary means of lowering soil and dirt pH and should not be confused with sulfate forms.

Suggested organic sulfur amendments:

  • sulfur (elemental - powdered - soluable)
  • epsom salt (magnesium sulfate)
  • agricultural gypsum (calcium sulfate)
  • sulfate of potash (potassium sulfate)
  • sulfate of potash, magnesium (such as Sul-po-mag®)

Magnesium

Magnesium is needed by plants to make the green pigment chlorophyll and to activate some enzymes.
Although there may appear to be a lot of chlorophyll in plants, each chlorophyll molecule only contains one magnesium atom.
Enzymes are catalysts and are only needed in small amounts to catalyse reactions, as they are used over and over again, another reason only very small amounts of magnesium are needed.

Suggested organic magnesium amendments:

  • dolomitic limestone (magnesium carbonate)
  • epsom salt (magnesium sulfate)
  • greensand
  • sulfate of potash, magnesium (such as Sul-po-mag®)

Micronutrient Sources (Manganese, Zinc, Boron, Copper, Iron, Molybdenum, Chlorine)

Manage soil and dirt to release forms of these elements already present by microbial activity.
Suggested organic amendment:

  • stable/finished/mature/aged compost

Nutrient Concentration and Function in Plants

Plants require 18 essential mineral nutrient elements for growth. Elements that are required or necessary for plants to complete their life cycle are called essential plant nutrients.

Each of these essential nutrients has a critical function in plants and are required in varying amounts in plant tissue. Macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium and sulfur) are plant nutrients required in the largest amount in plants.

Micronutrients (such as iron, copper, manganese, zinc, boron, molybdenum and chlorine) are required in relatively smaller amounts. Additional mineral nutrient elements which are beneficial to plants but not necessarily essential, include sodium, cobalt, vanadium, nickel, selenium, aluminum and silicon. The nutrient elements differ in the form they are absorbed by the plant, by their functions in the plant, by their mobility in the plant and by the plant deficiency or toxicity symptoms characteristic of the nutrient.

Nutrient Deficiency or Toxicity in Plants

Nutrient deficiency or toxicity symptoms often differ somewhat among species and varieties of plants. A nutrient deficiency occurs when the nutrient is not in sufficient quantity to meet the needs of the growing plant.
Nutrient toxicity occurs when a plant nutrient is in excess, and decreases plant growth or quality.

One way to understand the differences in nutrient deficiency symptoms among plants is knowing the function and the relative mobility of the nutrient within the plant. A description of the general symptoms of nutrient deficiency and excess often observed for those nutrients is supplied below.

Some nutrients, such as nitrogen, phosphorus, potassium, magnesium, chlorine and zinc, can be easily remobilized within the plant from old plant parts to actively growing plant parts such as young leaves.
Other nutrients, such as sulfur, iron, copper, manganese, boron and calcium, are not easily remobilized within the plant.
Therefore, the deficiency of the mobile elements usually initially occurs with older leaves while that of the immobile nutrients occurs with the young leaves or stem tips. Five types of deficiency or toxicity symptoms are observed:

  • Chlorosis - yellowing of plant tissue due to limitations on chlorophyll synthesis. This yellowing can be generalized over the entire plant, localized over entire leaves or isolated between some leaf veins (i.e. interveinal chlorosis).
  • Necrosis - death of plant tissue sometimes in spots.
  • Accumulation of anthocynanin resulting in a purple or reddish color.
  • Lack of new growth.
  • Stunting or reduced growth - new growth continues but it is stunted or reduced compared to normal plants.

Plant Nutrient----Type------Visual symptoms

Nitrogen-----Deficiency---Light green to yellow appearance of leaves, especially older leaves; stunted growth; poor fruit development.
Nitrogen-----Excess-------Dark green foliage which may be susceptible to lodging, drought, disease and insect invasion. Fruit and seed crops may fail to yield.
Phosphorus---Deficiency---Leaves may develop purple coloration; stunted plant growth and delay in plant development.
Phosphorus---Excess-------May cause micronutrient deficiencies, especially iron or zinc.
Potassium----Deficiency---Older leaves turn yellow initially around margins and die; irregular fruit development.
Potassium----Excess-------May cause deficiencies in magnesium and possibly calcium.
Calcium------Deficiency---Reduced growth or death of growing tips; blossom-end rot of tomato; poor fruit development and appearance.
Calcium------Excess-------May cause deficiency in magnesium or potassium.
Magnesium----Deficiency---Initial yellowing of older leaves between leaf veins spreading to younger leaves; poor fruit development and production.
Magnesium----Excess-------High concentration tolerated in plant; however, imbalance with calcium and potassium may reduce growth.
Sulfur-------Deficiency---Initial yellowing of young leaves spreading to whole plant; similar symptoms to nitrogen deficiency but occurs on new growth.
Sulfur-------Excess-------May cause premature dropping of leaves.
Iron---------Deficiency---Initial distinct yellow or white areas between veins of young leaves leading to spots of dead leaf tissue.
Iron---------Excess-------Possible bronzing of leaves with tiny brown spots.
Manganese----Deficiency---Interveinal yellowing or mottling of young leaves.
Manganese----Excess-------Older leaves have brown spots surrounded by a chlorotic circle or zone.
Zinc---------Deficiency---Interveinal yellowing on young leaves; small leaf size.
Zinc---------Excess-------May cause iron deficiency in some plants.
Boron--------Deficiency---Death of growing points and deformation of leaves with areas of discoloration.
Boron--------Excess-------Leaf tips become yellow followed by necrosis. Leaves get a 'scorched' appearance and later fall off.
Adapted from: W.F. Bennett (editor), 1993. Nutrient Deficiencies & Toxicities in Crop Plants, APS Press, St. Paul, Minnesota.

pH Adjustments

To RAISE pH - if lower than 7.0 neutral

  • compost, compost tea or well-aged leaf mold and ramial wood (These organic materials will produce a pH moderating effect on soil, but only over time, and multiple applications may be required)
  • calcitic limestone, powdered
  • dolometic limestone, powdered
  • clean wood ashes
  • Agronite

To LOWER pH - if higher than 7.0 neutral

  • compost, compost tea or well-aged leaf mold
  • elemental dusting (wetable) sulfur

Soil Conditioners

  • composts, compost teas or well-aged leaf mold and ramial wood
  • aged grass clippings
  • humates and fulvic acids
  • greensand
  • gypsum, agricultural (powdered)
  • mulches that decompose without causing a nitrogen deficiency
  • organic rock powders
  • sugar sources (molasses, glucose, sucrose) as microbe stimulants
  • peat moss (although peat moss is widely used as a soil conditioner, it is not recommend because harvesting destroys increasingly rare bog habitats.)

Microorganism Inocculants

For composting standard feedstocks microbe inocculants such as 'stimulators' and 'activators' are NOT necessary.
While not harmful, such are a waste of money and time for compost piles and/or in-ground application. Particularly GMO (Genetically Modified Organisms) Do not use GMO's.

Mycorrhizal fungi are not normally a derivative of the aerobic, thermophilic composting process.
Recommend adding some native soil (in which mycorrhizae are known to thrive, or an Endo mycorrhizal product after the 2nd turn of the composting process.
For conifer planting, Ecto mycorrhizal is the product of choice.
For more information see: http://www.mycoapply.com.

Dirt Mixes

Planting mixes and container/potting mixes SHOULD contain some quality aged compost and be watered with compost tea. Seed-germinating mixes should NOT contain compost or be watered with tea, to ensure maximum a germination and initial growth rate of seeds.
While compost is an absolutely wonderful organic product, no matter how it is made, the simple facts are:

  • distilled (or deionized) water is best for starting seeds
  • do not soak or water seeds with chlorinated water (which is designed to kill microbes)
  • compost contains a myriad of fungus microbe populations, some of which may be harmful for new seed sprouts that have not yet developed their immune system. Once a seedling has grown sufficiently to be taking up nutrients and water from its roots, it can be transplanted into a compost-based medium and watered with compost tea.

Sowing and/or planting of viable seeds directly in an organic growing bed (garden) is a common practice (particularly for seeds protected with a coating of Thiram or other seed protectant) - a common practice and particularly recommended for very small seeds such as radish, carrot, lettuce, etc., and let nature take its course.

Some gardeners use a mild organic fungicide that is known not to harm mycorrhizae fungus, which is a good idea for any garden bed in which seeds are placed directly in/on compost-based dirt.

More specifically, the issue mainly involves use of freshly-finished compost. Once a compost has fully aged, the microbe population diversity has had opportunity to 'settle', which tends to naturally eliminate any abundance of plant-harmful fungi in it.

Mother Nature knows what 'she' is doing with regard to microbe dynamics, and as long as conditions are not presented, which override 'normal' conditions (such as maintaining compost in 'soggy' condition, or watering plants with harmful fungi), it is not likely that any compost should cause concern - if proper proportions of the dirt recipe are maintained. On the other hand, this author raises many plants (including vegetables) in 100% compost occasionally. For research purposes of course...

In a separate section, will share some of ORG's "favorite" plant-specific dirt mixes for various plants, climates and growing conditions.

COMPOST CONTAINMENTS
Click Here to see: Compost Containments
COMPOST PILES
Click Here to see:COMPOST PILES