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The Invisible Garden: Probiotics & Soil Health

Earlier, I wrote about how BD500 works like a “probiotic” for the soil. I can understand some skepticism regarding that claim, but now I am going to talk about real probiotics in the sense most people are used to.

Many of you are familiar with Lactobacillus acidophilus, regularly found as a probiotic supplement in pill form or in cultured dairy products. This is more readily accepted than probiotics for the soil. But plants do not have organs the way mammals do: the soil is the stomach of plants.

The good farmer doesn’t just cultivate what he can see, the good farmer cultivates the secret garden below his feet. Lactobacillus can live in aerobic conditions or anaerobic conditions. Since it is a harmless bacterium, but can live in stagnant conditions, it is an ideal partner to the biological farmer. Lactobacillus permeates the soil, even water-logged soils, and begins to bubble. Many pathogens are anaerobic, so soaking the soil with EM·1® helps “crowd out” those pathogens. Colonizing soils with beneficial bacteria helps “crowd out” harmful bacteria.



Towards this end, cousins of L. acidophilus are employed when we use EM·1® Microbial Inoculant. This contains water, molasses, and several varieties of bacteria. This culture can be “activated” in a few simple steps.

How does BD500 play into this? BD500 is a special compost tea that has undergone a gentle fermentation. The result is a microbe- and enzyme-rich spray that feeds the food chain from the bottom up. If you do not put much stock in biodynamic agriculture, I would commend a good compost tea to you. I have some results with BD500, but Bountea might be of interest to those who are not interested in BD500. For those on a tight budget, as most of us are, consider using a weed tea.

I also use MycoGrow™, one of Paul Stamets’ superior products. This has a wide range of endophytic and ectophytic fungi along with numerous varieties of beneficial bacteria. I like to soak roots in MycoGrow™ to encourage colonization.

Mycorrhizal Fungi

Mycorrhizal Fungi

The bacteria in both MycoGrow™ and EM·1® form polysaccharides that help protect plants droughts and thus from infestation and make accessible nutrients to leaves that otherwise would not be available. Mycorrhizae are fungi that form a special symbiotic relationship with the roots of plants, with some exceptions such as brassicas. Mycorrhizal fungi, by “infecting” the roots in plants, help prevent infections by rival fungi — the same with colony-forming bacteria.

Note: if you are planting blueberries, usual mycorrhizal fungi will not work. You must find ericoid mycorrhizal fungi. The only source I have found is called Rhodovit® and it is made in the Czech Republic. The dealer I found in the USA is here.

There is a not an uncommon practice of applying molasses to fields in order to encourage beneficial bacteria to populate the surfaces of the plants. EM·1® is 96% water, 3% molasses. The active ingredients include Lactobacillus that digests the molasses readily. With only a small original amount, enough is quickly made to spray your entire property.

For example, if the soil gets wet, the symbiotic fungi will grow vigorously instead of harmful fungi that might cause the tree to rot. Mycorrhizal fungi extend the reach of roots greatly, accessing nutrients otherwise “locked” away to trees and plants. In exchange, the plants excrete waste substances of use to the fungi.

While it is fine to use a diluted fish emulsion spray without thorough mixing, I think it is beneficial to use a simple aquarium pump to oxygenate the mixture at room temperature or above. If there is foam, that is a good indication of aerobic life. Populating your mixture with aerobic bacteria I think is a worthwhile addition to your spraying program. Of all organisms in the soil, bacteria have the highest protein content. Many pathogens are anaerobic — living without oxygen — so the simple introduction of oxygen to your mixture will greatly improve its use and decrease the risk of infections. The conventional biodynamic method of incorporating oxygen and bacteria is by stirring for extended periods of time. Not everyone will feel like they have the time for this activity. But even if stirring a mixture manually for sixty minutes is the best, I will go out on a limb to say that using a regular aquarium pump and leaving it for a full hour will do your mixture no harm. I think it does benefit my plants. Your fertilizers should incorporate microbes. If they do not, something alive will show up — and it might not be what you want.

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