Soil Biology - Nothing But Normal and Natural

I find that many of our customers believe that the introduction of mycorrhizal fungi to their plant root systems is adding an "extra" benefit - something like a new and improved fertilizer. It's not. Actually, a biological approach to growing healthy and productive plants is simply trying to copy normal and natural methods that have evolved over millions of years.

Mycorrhizal fungi are a key element in an overall ecosystem, as described in earlier newsletters (see the Archive section at our website - www.bio-organics.com). Most notably the fungi greatly enhance and regulate the uptake of nutrient and moisture by plant roots, along with protecting their host plants from pathogens and diseases.

Plants have their function in a healthy soil system, too. They are uniquely equipped to perform photosynthesis - gather and transform sunlight into nutrients (photosynthates).  The plant roots then serve as a "give and take" nutrient exchange site - some of the plant's photosynthates directly and indirectly nourish beneficial soil organisms; while in return those organisms gather, digest and deliver essential nutrients to the plants.

The details and components of this complex nutrient producing-and-exchanging system can be found in any modern soil biology textbook, but for our purposes it is enough to recognize the interdependence of plants and living things in the soil. Because of the way they are linked together in nature, neither can enjoy full health without the presence of the other.

When a plant is set into lifeless soil, or into soil that lacks the correct microorganisms to match up with that type of plant, the plant suffers from, essentially, starvation. On their own, many plants lack the ability to effectively uptake nutrients. Foraging is not what plant roots are designed to do - they are like anchoring pipelines that have limited surface contact with soil (as compared to fungi with millions of root-threads that make contact with huge amounts of soil).

Humans have learned to deal with fungi-lacking starving plants: Feed them fertilizers, placing abnormal amounts of NPK in the root zone, so even inefficient root systems uptake enough macronutrients to perform adequately - but not optimally. No amount of synthetic limited-ingredient fertilizer can substitute for the ideal bio-origin nutrients.

Again as noted in earlier newsletters, this direct-feeding of plants has some serious downsides which are becoming obvious after a few decades. For homeowners, chemically-dependent lawns are the worst problem,as such lawns need near-continuous applications of "plant food" to keep inefficient grass green. For farms, heavy fertilization and the resulting loss of soil bio-life causes compaction and salt buildups. Plus, the growing contamination of water supplies with nitrates and phosphates from this heavy fertilization should be a concern to all.

The general solution is to have a goal of increasing beneficial life in soil. The old phrase, "Feed the soil, not the plant" has perhaps more truth than even most "expert" growers realize. I suspect because it is difficult to measure the soil biota. It's much simpler to recommend chemical tests (which invariably lead people to "fix" and damage their soil).

Let's be clear, putting a big handful of 10-10-10 in a planting hole is NOT what's meant by feeding the soil!  And 10-10-10 fertilizer is NOT "complete", nor is it in any way "balanced". Those are marketing terms that I see in print over and over again as accepted facts.(My teeth would be a bit longer if not for the grinding that those two words have caused.)

Feeding soil means adding composted material and using organic mulches, plus occasionally scattering trace minerals and small amounts of dry low-analysis fertilizer (such as fish pellets). Ideally, it means adopting no-till or limited-till practices to avoid disrupting the underground networks of beneficial living organisms that plants link into.

It may seem self-serving, but I do believe that the use of biological inoculants is also a key part of any soil enhancement project. A one-time addition of mycorrhizal fungi spores (that also carry beneficial bacteria with them)ensures the presence of perhaps the single most important soil organism - the one that bonds all the plants and soil life together. Please note that this is all normal and natural - NOT some miraculous new additive - and promises the ultimate sustainability. A biological orientation builds up the soil's production capacity, instead of depleting it.

And speaking from personal experience with my vegetable gardens over the years (too many years), seeing my robust plants now perform closer to their full genetic potential with minimal input is exciting stuff. My investment in soil life is paying off in stronger plants with bigger yields than I ever had under chemically-oriented methods. Anyone who would now try to drench liquid fertilizer on my garden beds would quickly gain some hoe-handle marks on their rump!  
Cheers, and good growing, friends.

Don Chapman
President, BioOrganics, Inc.
www.bio-organics.com
October, 2003