Amendments and fertilizers are all the rage to supply nutrients for plants. But what if we told you that compost is the best way to supply nutrients for your plants? This post will dig a bit deeper into the life of your soil to look at how a healthy soil food web cycles nutrients.
The Soil Food Web
This diagram is from the USDA's Soil Biology Primer (2000). In which Dr. Elaine Ingham and others detailed how the soil food web organisms work with the plants, environment and other organisms to create a true living soil.
It is all about the relationship of the trophic levels in the soil and these levels are:
Photosynthesizers (plants, exudates and OM)
Decomposers, Mutualists, Pathogens, Parasites, Root feeders (bacteria and fungi)
Shredders, Predators, Grazers (protozoa and nematodes)
Higher Level Predators (microarthropods and predatory nematodes)
Even Higher Level Predators (birds and animals)
Bacteria and fungi play a major role in the Soil Food Web (SFW). They feed off the photosynthetic material and plant organic matter (OM) to release nutrients to plant roots.
Breakdown of OM by microorganisms changes nutrients from exchangeable (bound) to soluble nutrients in plant available form.
Bacteria and fungi will also feed off the parent material (sand, silt, and clay) to release the nutrients stored in the lattice like structure. The molecules of N, P, K, B, Ca, Fe, etc. are then released and ready to be cycled.
Plant roots release exudates that are simple sugars, carbohydrates and proteins to attract the bacteria and fungi to the root zone. Here the poop loop does all the work
The Poop Loop
The nutrient dense bacteria and fungi are all congregated in the root zone attracting the predators. Protozoa and nematodes feed off the nutrient dense bacteria and fungi. They will keep the nutrients they need and poop out the rest. Different microorganisms have varying levels of C:N ratios, different fungi have varying C:N ratios depending on age! Bacteria will have a low C:N but protozoa can eat up to 10,000 bacteria per day. Therefore the protozoa are pooping out a lot of soluble nutrients. These nutrients that are
pooped out are now in plant available form and conveniently located in the root zone! Here the poop loop takes us from plant exudates to nutrients in plant available form. And like nature this predator prey relationship will regulate itself to keep balanced levels.
So What?
So what does this mean for growers? If your soil has a healthy balance of bacteria, fungi, amoeba, flagella, and nematodes you will have nutrient cycling! These can be introduced with BioComplete Compost, and other products. Compost and compost extract applications will introduce biology into your soil and kickstarting nutrient cycling. Let the microorganisms do all the work for you.
At The Glen Road Organics we grow all our products without fertilizer, pesticides or herbicides, we practice what we preach here. The only way we amend the soil is with compost and build OM with winter kill cover crops.
These nitrogen nodules are found on legume crops. Bacteria will form a relationship with the plant root where the nodules will supply nitrogen from the atmosphere directly to the plant. When the plant has enough, the nitrogen is then released back into the soil. There is no shortage of nodules in our garden in the summer showing us the soil is productive and aerobic! If plants can turn atmospheric nitrogen to organic nitrogen why do we add extra?
While compost does not have the concentrated N-P-K values it adds value in more stable and long lasting nutrient cycling. Not all the nutrients are in plant available form right away leading to less leaching and more nutrients release over time. Nutrient cycling does not only cycle the macro nutrients but he micro nutrients as well. By building an active healthy soil you are building up plant available nutrients and eliminating the need for fertilizers.
To learn more click here https://www.soilfoodweb.com/
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