by Tony AventWritten for The News and Observer, Raleigh NC March 26, 1994
Have you ever wondered why those plants that you gave up for dead, and threw on the compost pile, magically come back to life and grow to monstrous proportions...thriving without any fertilizer or care? Why is it that the grass, that refuses to stay alive and healthy in the lawn, but upon moving into the mulched flower beds, it grows like never before? Why ask why?
The catch word is organics. For every organic gardener, there is a different definition about what is organic. Before you get your back up, let me say that I am far from being a granola crunching, Silent Spring toting, environmentalist whacko (borrowed the term). As one who started out as an advocate of using chemicals as needed, my views have certainly changed with introspective experience and an increase of knowledge.
Let's use as our definition of organics, the process by which everything that lives must die, and return its elements to the soil to produce future generations. In organic gardening, everything is in balance, allowing the sub-microscopic elements of our soil to perform their tasks of keeping the soil healthy.
By using a good organic system of gardening, plants remain healthy and free from stress. Just as people reduce stress in their lives, through exercise, diet, and a myriad of other late night advertised cures, plants must do the same. We realize that stress causes us to be more susceptible to diseases and other ills, the same is true for plants.
In many ways, organic gardening had gone the way of alternative medicines, being shunned by government researchers who in many cases simply are not gardeners, but chemists. Understanding a chemical reaction in a lab often doesn't take into account the complex soil system and its interaction with the plant. What's more, field tests are usually performed over a short period, during which chemical fertilizers can equal any organics. Where the comparisons fail is in the long term.
By now, I have probably lost those of you who fail to see the need to plan for the future (since you might not be here tomorrow), and still insist on living only for today. Organic gardening is sort of like eating. You will have lots of energy by relying on a diet of cheeseburgers, fries, and ice cream for desert...wonderfully satisfying in the short term, but you pay for it in the future.
Does one fast food meal hurt you in the long run...of course not, but a steady diet does. It's not that the fast food doesn't have plenty of nutrition, it's just that some of it is in forms that just don't do a body good...sort of like lifeless fertilizers.
Some left wing organic gardeners accuse bureaucrats of a conspiracy with fertilizer companies, such is nonsense. In reality, the chemical and fertilizers companies do fund research designed to test certain aspects of their products. For the most part, organic fertilizer companies have not spent the money on such testing, and don't have stacks of slick publications at every garden center.
Finally, with less organic materials being allowed in landfills, researchers are beginning to look at uses for organic products. As with all recycling, ideas are no different, as we return to some of the common sense ideas of past generations, before the advent of chemical fertilizers.
As always, growing a good plant begins in the soil. Our soil is much more complex than the sticky red clay that most of us see when we go outside to garden. All too often, gardeners look at the clay, decide that it will never grow anything, then dump handfuls of 8-8-8 fertilizer on top to "make things grow."
We have become content to use the "Baby Ruth Bar" for energy mentality by creating an artificial diet for plants, which is neither beneficial for the plants or the soil in the long run. As anyone knows, 8-8-8 when used properly can make almost anything grow...at least for a short time.
The first concept that we as gardeners need to change, is to learn to fertilize or feed the soil, not the plants. If the soil is well balanced with organic matter and microbes, the plants can acquire nutrients on their own schedule. You are probably wondering if all of the chemical fertilizers are bad, and the answer is no. By the same token, all organic fertilizers are not good...everything must be in balance.
Sewage sludge is organic, but must be used with caution. Depending on the source, the material may have very high levels of heavy metals that can render a soil useless for growing anything, except maybe kudzu and crabgrass. By the same token, a slow release fertilizer, low in salts may not damage the microbes in the soil, while providing essential elements for plant growth.
A good demonstration of the importance of microbes in the soil is in a lawn. Have you ever noticed that during the winter, even a cool season lawn is off color. Then, as the soil warms up, even without fertilizer, the lawn magically turns green. How could this happen without fertilizer? What you are witnessing is soil microbes at work. Microbes are tiny microscopic organisms in the soil...sort of like the government workers of the soil. Each microbes has duties to perform as part of an entire community system.
As the microbes wake up from a winter sleep and become active, they begin processing the nutrients in the soil into forms that are usable by plants. In the book Microbe Power by Brian Forbes, a lab has collected 13,000 different soil organisms with the ability to break down molecules to release energy!
We have talked about these microbes, but what makes microbes work? There are three fuels that make microbes run, ammonia nitrogen, amino acids, and organic matter (complex nitrogen). All of these fuels are derived from decomposing organic material in the soil. In short, the more organic matter in a nutritionally balanced soil, the more productive the soil.
When high salt chemical fertilizers are applied, the grass may turn green, but the microbes are often killed. A more visible experiment can be performed by placing earthworms in a pan, then applying your fertilizer of choice. Do the earthworms crawl thru the fertilizer, away from the fertilizer, or simply die? The effect from the chemical fertilizers are temporary at best, while the effect from properly fed microbes is permanent.
For years, we have all heard that Nitrogen is Nitrogen, despite its source...true or false. If this is true, and since our atmosphere is mostly Nitrogen, plants should never need fertilizer. Of course, we know that this is not the case.
Nitrogen, before it can be used by plants must be converted by the soil microbes to either a usable form of Ammonium or Nitrate. In addition, Phosphorous must be converted to Phosphate, sulfur to sulfate, chlorine to chloride, and the list goes on.
A well managed soil should contain 5 percent organic matter. With adequate organic matter, the soil becomes alive. An organic soil is able to hold and process nutrients as well a hold water during drought. A soil with 5% organic matter can hold almost 200 pounds of water in every 100 pounds of dry soil. A similar soil with only 1% organic matter can hold only 30 pounds of water in the same soil.
Now, before you go getting all excited, let me tell you that to get a 5% organic soil, you will need 50 tons of organic matter per acre! I mentioned that this is a long term proposition. Organic matter can be added to the soil in one of three ways, through incorporation prior to planting, through the use of organic fertilizers, and through the use of an organic mulch.
One of my favorite ways to add organic matter to the soil is to incorporate the organic matter during the preparation of the bed. Good materials which are available locally include decaying leaves, old composted sawdust, ground pine bark, compost. Ideally these materials should be incorporated into the top 6-8 inches of the soil.
If you are planting in individual holes, this method is completely useless, since the roots are hopefully not going to remain in the holes for a very long period. With this method of planting, or in established plantings, you must resort to one of the other two methods of introducing organic into the soil.
Mulching is of great benefit, although in the south, organic mulches seem to break down fast. As the mulches break down, they produce humic acid. The humic acid is the materials that works hand in hand with the soil microbes to break down the nitrogen sources so that they are in a form usable by the plants.
Having tried a lot of different mulches, I find shredded hardwood bark to be my favorite. Not only does this type of mulch last longer (which prevents weeds), but I can watch the humus changing the color of the soil underneath. Almost all organic mulches are good, so don't be shy.
The third method of adding organics to the soil is through fertilizer. This is the most underused means, and probably the most needed, since we are so often dealing with established plantings and lawn areas.
One of the biggest problems in growing lawns, is the lack of any addition of organic matter to the soil, hence the need for large quantities of commercial fertilizers. Finally, it has become politically correct to let clippings fall back into the lawn...that one took a while!
The lawn clippings by themselves are of no benefit without microbes to help them decompose. If we are killing the microbes with high salt commercial fertilizers, what have we accomplished. Through the use of organic fertilizers, we need to correct the nutritional balance of the soil. It is at this point that the microbes begin to work for the soil.
Most turf diseases in home lawns can be easily avoided without the use of chemicals. First the maintenance of the lawn must be performed properly...cut the right height, etc. By having the soil microbes at work, and the nutrients in balance, the lawn grasses are no longer under stress. As we have talked about stress earlier, the less stress...the less diseases !
Being a good organic gardener has been tough, due to the lack of mainstream information. In that vein, I want to recommend a book for everyone that deals with soils and soil chemistry in an easily understandable format. The book is An Acres USA Primer by Walters and Fenzau, ISBN 0-911311-37-8 by Acres USA Press.
At this time, organic fertilizers are sort of a catch-22 proposition. There are a number of organic fertilizer lines on the market, but very little good information to go with them. We have worked closely with Fertrell, a Pennsylvania company that actually manufactures many of the products on the market under a variety of trade names.
What makes a good organic fertilizer. It's not simply putting some cow and chicken manure together in a bag. Just as chemical fertilizers are mixed with a little of this, and a little of that, the same process is followed in the manufacture of organic fertilizers. Organic fertilizers, as a general rule, are not something that is dug out of the ground and sold.
The use of organics fertilizers without knowing the desired result, is of little more benefit than using chemical fertilizers. The information demand from consumers must increase, before the information will become available. Organic fertilizers must be used in conjunction with information from your soil tests, which unfortunately are also lacking in much necessary information.
As I have warned many times, beware of the magnesium and calcium levels in the soil, for it is their balance (5:1 calcium to magnesium ratio) that controls the availability of Nitrogen, Phosphorous, and Potassium to the plants. Unfortunately lime recommendations are made without regard to whether these readings indicate a need for calcitic (without magnesium) or dolomitic lime (with magnesium).
Finally, there are a few good organic landscape companies in the area, so check the yellow pages. To me, organic landscaping does not mean, simply not spraying chemicals, for this in and of itself will not work. The reduction in chemical usage, MUST be accompanied by a program of stress reduction through soil nutritional balance, increase the use of organic matter, and good maintenance techniques.
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