How to create fertility without buying fertiliser.
Here’s an article about fertility, biofertilizers, and taking care of your soil. It it well written with some short history about commercial farming.
The article continues by going in depth into the fertility and soil food web and the microbial inhabitants of the soil. We have talked at length about soil fertility and how it is linked to healthy soils. Living soils are the most important part of any farm or garden.
There is a common misconception in the farming world that’s harming your profits and potentially your future. We’re led to believe – in increasingly clever and technical ways – that we need fertilisers in order to increase the productivity of pasture or meadow. But just as humans aren’t ‘statin deficient’ when they have a heart attack; grasslands aren’t ‘fertiliser deficient’ if their performance is poor.
How to create fertility without buying fertiliser.
The study of soils has come on enormously in the last few years. Before 1980s scientists had little idea that soil organisms were important to plant health, through the ‘green revolution’ agriculture has been dominated by chemical solutions. Now, due to recent scientific findings, I’m confident that the next wave of high production agriculture will be led by those who understand the biology of our soils.
Minerals come from rocks. Every soil in the world has the potential to grow plants. Some rock is weathered into soluble forms that plants can absorb directly through their roots and then are recycled back through the decay process – this is the ‘soluble pool’ that shows up in a soil analysis test. But how do we access the limitless ‘total pool’ available in the crystalline structures of the rock that can provide the full 42 of essential nutrients plants really need to be healthy and disease resistant?
This is where your underground army is required. Every spoonful of healthy soil contains a billion or more microorganisms. In healthy grassland there’s approximately the same weight in earthworm biomass as the weight of the cattle grazing above ground, not to mention the thousands of other tiny critters all shredding, digesting, dissolving and excreting to gradually improve your soils.
The mineral cycle is that; a cycle. But to understand it we should start – as the earth did – with bare rock and some bacteria, fungi and algae. These microorganisms use enzymes and acids to break down the rock and access the nutrients. With no soil in which to reside, the bacteria, fungi and algae form symbiotic relationships to create a plant like species called lichens. These communities can then offer a home to mosses and lower ‘successional’ species. Gradually the cycle of growth, death and decay builds enough soil for whole plant communities to thrive.
The more complex the plant community the better overall access the minerals in the soil. Different species have different root depths, soil preferences and water tolerance. The plant will grow deep roots if the foliage can develop mature leaf, this will help it access a higher concentration and wider range of the soluble nutrients. Minerals tend to leach downwards as rain passes through the soil layers, deep roots help transport minerals back upwards.
Dead plants, excretions from grazing animals, and other organic matter pass some of these recycled minerals in a plant available form back into the top layers of the soil again. But the real potential to make free fertiliser forever is in the so-called ‘microbial bridge.’
When the sun shines, plants photosynthesise. The plant makes food, some for itself and the rest – 40% ish – is passed out of its roots as an exudate of sugar, carbohydrate and protein, or, as leading soil ecologist Dr Christine Jones calls it ‘liquid carbon.’
This juicy cocktail attracts and feeds bacteria and fungi who, through solubilising rock mineral, have a biomass filled with the essential nutrients our plants can’t access. In turn, these bacteria and fungi attract predatory organisms like protozoa and fungal eating nematodes who eat them releasing nitrogen, phosphorus, sulphur, magnesium, potassium sodium, iron, zinc and more, in a handy dandy plant available form. The whole process takes seconds and conveniently happens right next to the plant roots where it can be easily absorbed – no waste, no leaching, just an ‘on tap’ source of everything your plants need. Here’s the rest……