Marco Banks wrote:It would appear to me the just as important (or perhaps even more important) as introducing beneficial microbes to your bio-system, is to create a habitat for those microbes to continue to live, thrive and multiply.
Thus, while the evidence of the benefit of compost teas, comfrey tea, etc. is still largely anecdotal, with scientific studies showing mixed and inconclusive results, we do know that soil that has high levels of carbon and a multiplicity of living roots will be thriving with biological/microbial life. So it doesn't make much sense to go to great lengths to brew microbial-rich teas if we are introducing them into soils that will not be able to support them. Please hear this: I'm not in any way against microbes. Clearly they are an essential keystone to the soil food web. But the question of whether or not the best way to build microbial communities is via compost and comfrey teas is still very much open to debate. But what we do know is that if you build the "house" for them, they'll come into that house and take up residence.
Imagine going to a pet store, buying a dozen tropical fish, and then dropping them into an empty aquarium. They look full of life . . . for a bit . . . flopping around, and doing fish stuff . . . but within a short time the environment I've introduced them to will not sustain them.
I believe that most soil has the parent material for all the microbes you will ever need ---- but we need to create the environment for them to multiply and thrive. (Putting the water into the aquarium). By dumping copious amounts of carbon onto the soil surface via organic mulches and chop and drop gardening, you create the habitat your microbes need. In the rare circumstance where there are not adequate soil microbes, a one-time "jump start" of compost or compost tea might be needed to introduce these microbes, but from then on, you only feed the system, not the tea.
Every time it rains on my food forest, I am getting thousands of gallons of compost tea spread over the surface of my food forest. How? I've got 6 inches of wood chips, mulching and decomposing on every open surface, and thousands of plants pumping root exudates into the soil. That rain washes through the composting wood chips and pushes those microbes down into the root zone of those plants, where they feed on the sugars provided by the plants. I'm not brewing anything, but I don't have to. Further, because plants self-select and feed the microbes that they find most beneficial, I don't have to worry about brewing the "right" kinds of microbes: the plants are already doing this for themselves.
As permaculture is all about biomimicry, this is exactly what is taking place in a forest. The rain washes through the carbon layer on the forest floor, and the microbes there-in wash down into the soil profile. No one is brewing compost tea out in the forest, but the soil is getting everything it needs. Nowhere in nature will you find compost teas being sprayed onto the leaves of trees.
Build the right home for the microbes, and they'll multiply and distribute themselves aggressively. But if you are pouring microbe rich teas onto denuded and bare soils, it's a lot of effort for minimal return.
Bravo, sir. Great post.
