Jeff Lowenfels is the popular and well-respected writer of three important books on plants and cultivation. He is the co-author of “Teaming with Microbes: The Organic Gardener’s Guide to the Soil Food Web,” published in 2006 to great acclaim and revised in 2011. It is touted as the most important gardening book published in the past 25 years and won the prestigious Garden Writers of America gold award. His other works include “Teaming with Nutrients: The Organic Gardener’s Guide to Optimizing Plant Nutrition” and “Teaming with Fungi: The Organic Grower’s Guide to Mycorrhizae.”
Lowenfels is also a national lecturer and a fellow, hall of fame member, and former president of the Garden Writers of America. Passionate about organic and sustainable gardening, he co-wrote Teaming with Microbes to educate gardeners everywhere about the soil food web. The book contains 19 rules, Jeff jokes that it used to contain 20 rules, but the 20th was to not loan the book to anyone and make them buy their own copy.
Symbiosis: A process of supply and demand
The essence of the soil food web is the symbiosis of plants, soil, and microbes, and the cannabis plant is an unbelievable user of it. If you learn the system, Jeff explains, “you can grow not only the best plant, but … with the least amount of work, which is after all, what we all essentially should be striving for.”
He describes a clever supply and demand system in which the plant puts out exudates to attract microbes who will provide the food the plant needs. It works like this. The plant drips exudates out of the root system into the rhizosphere, the area around the root, and attracts bacteria and fungi to feed on the carbon contained within them. In turn, the bacteria and fungi attract protozoa and nematodes who feed on them and then excrete nitrogen in plant-usable form back into the root zone. Jeff equates exudates to human sweat, “Whether you know it or not, you’re exudating, you’re giving off sweat.” Incredibly, 50-60% of a plant’s photosynthetic energy is spent producing these exudates and the plant is in control of that output. It can change the composition of the exudates, in order to change the make-up of the microbes it attracts to the root zone and in turn, the nutrients they excrete back into the soil.
It doesn’t end there, there are bigger creatures who eat the nematodes and the protozoa, and even larger creatures who eat them. The soil is held together by slime created by the bacteria, which fungi then weave through and create pockets of air and water holes; places where the creatures can hide from each other. All of it a collection of food chains. As Jeff explains, “Every now and then, one of the critters on the chain looks up or looks down and sees another chain and finds something on that other chain that it can eat, and it eats it. It connects those two.” This results in a fence of linked food chains, and at the base are the microbes, but at the center is the plant. Jeff reiterates, “The plant is in control.”
Feeding and healing
According to Lowenfels, soil is best for growing cannabis plants, and the best soil is well structured with a good food web at its heart. He uses his soil again and again, adding organic matter and mulching well. Although he cuts off his male plants, he leaves the root system in the earth to enrich the soil, “That male plant has been producing exudates and attracting the right kind of microbiology to feed a cannabis plant. So, why would I want to throw it away?” Soil food web knowledge isn’t just important for feeding plants, but for healing them too. It can mean knowing what in nature would take care of a problem. As Jeff puts it, “What other member of the soil food web would eat this particular problem, or what member of the soil food web would eat what this particular problem eats and therefore starve it out?”
Organic is the answer
Once you know the system, it is easy to understand why Jeff is such a proponent of organic growing. He believes using chemicals and pesticides is ultimately limiting, that even if the grow is successful, the product won’t be of good quality. “I don’t even want to use the word inferior,” he clarifies, “if it’s got a pesticide, that’s chemical, it’s not usable. Period. I guess you could make oils out of it.” And while chemical fertilizers, like Miracle Gro, do work, they replace the bottom of the soil food web destroying its delicate balance. Jeff laments, “You’re not forming this wonderful sustainable system where the microbes are feeding the plant based upon sunlight energy.” The fact is, if given a chemical fertilizer, the plant no longer needs to produce the exudates to attract microbes, and while fertilizers don’t kill all of the microbes, they do feed certain ones and starve others. It’s not just the plant that benefits from the microbes’ deposits, humans do too. The microbes place into the soil things that make for a healthy plant, which includes antibiotics that we harvest.
This is why it is so important to grow organically, and the way to grow organically, is to use the natural system, and the natural system is the soil food web. Jeff always ends his talks with this fact, “This is the system…that the redwoods used to grow for 500 years and [reach] 750 feet tall. This is the system that all plants use.” What could be better than that?