Crop rotation is a system of growing different types of crops in succession on same land, based on the crop family (legumes, greens/brassicas, fruit and root), usually following 3-4 year cycle (see chart below). There are two common reasons for this practice:
1. preventing nutrient depletion
2. preventing of pest and disease build up
But is this system tackling the root cause of the problem or just the symptoms? And how useful it is? How there are so many problems with pests and diseases in current agriculture and growing system? Are plants really so weak that they need our constant management, fertilizing and spraying with chemicals for them just to survive? Or did we created this problem ourselves, and how can we really solve this?
To answer these questions, we need to understand Nature`s two most fundamental principles:
1. Nature`s law of return
Law of Return or Wheel of life is never ending cycle of life and death. Every living organism is born, lives and dies. The nutrients and organic matter are recycled and returns back to the system for new generation to be born and thrive. Life comes out of soil and needs to return back to the soil. But current agriculture and farming systems broke this wheel of life and only takes out of soil, reducing the organic matter every year and upsetting nutrient balance and soil microbiome.
2. Survival of the fittest
Survival of fittest is the survival of healthiest. Nature`s second most fundamental principle is based on predation. Sick and diseased perish and only the healthy will survive and pass on genes whether it`s animal or plant. In animal kingdom predators kill weak prey, and plants get attacked by diseases or pests.
Symptom is not a root cause
Predation is nature`s way to avoid spreading weak or sick genes. So the real problem is not the pests and diseases, they are only the symptoms of a problem which is the agriculture system and our treatment of soil.
Intensive farming mostly takes out of the soil, forces plants into grow with concentrated chemical fertilizers, killing all living things with pesticides, tilling and rotavating disrupts the soil microbiome that can live only in the soil sub layers, and mono-culture plantations.
However using chemical fertilizers is short term solution and creates bigger problems as weak crops, soil organic matter depletion and soil microbiome collapse. And when that happens soil will eventually fail to support any plant growth even with fertilizers. There are many examples of previously fertile lands that are now dead zones and useless for growing crops.
While lack of organic matter is biggest problem, we are also creating another problem by growing mono-cultures and limiting crop varieties. Plants that have similar or same genome are at several times higher risk of spreading disease, attacked by pests and failing. Nature thrive on variety, so bigger the variety the more stable and healthier is the whole system.
Pesticides were marketed and promised the solution. But they did not address the root cause but just symptoms, they delayed and exaggerate the problem by creating pesticide resistance, so more and more need to be used and polluting our environment.
is it that many people still fail to understand the importance of healthy soil and nature in general? There are many, from decades of incorrect assumption that soil is dead and only good to anchor plants so they don't fall, egoistic believe that we are apex species to rule the nature, lobbying and advertising of chemical industry, outdated education, but the most fundamental is belief that we are separate from nature. And nothing can be further from truth! We are all interconnected on incomprehensible level, part of the life web and what we do to nature we do to ourselves.
was always in plain sight only for those who bother to look. There are rice fields in Asia that grows same crop for centuries with no major issues.
Charles Dowding, the proponent of organic and no dig method grow successfully in trial beds of some vegetables for several years in a row.
Albert Howard in his book The Soil and Health summarized lifetime of his scientific and field studies and trials on organic vs conventional agriculture. Study after study, trial after trial he was able to prove the power of organic growing system not only as a prevention but also cure for already diseased plants. He attributed this to fact that when plants are growing with chemicals the proteins are not synthesized properly and plants are more prone to diseases and pests attack, which is only nature doing it`s thing. By switching to organic system the bad proteins are replaced by properly synthesized ones resulting in improved health.
Common denominator is Organic growing that has been here for centuries and even during famines where the majority of crops failed or could not sustain growing populations, there were some crops still thriving.
To fix current problems we need to fix the Wheel of life and return organic matter to soil. By increasing organic content of soil you improve water retention and nutrient availability to plants, create healthy microbiome that will establish symbiotic relationship with plants and the whole system will thrive. Scientist already discovered that fungi network acts as informational highways where plants are able to send information to each other, for example when one plant is under pest attack it will send signals to other plants to start making defensive chemicals or close up root pathways due to presence of pathogenic fungi. Just mind-blowing stuff!
Rotate or not to rotate?
It certainly does no harm if you swap crops, and it can be useful tool to keep the plants and soil healthier. But if that is the only solution to fight pest and diseases, without caring for soil it is destined to failure. And you can`t rotate plants like trees, shrubs and ornamental plants. I myself try not to grow same crop over and over in same area but I`m not fussed about it and do not follow any strict rotation regime. With small growing area to work with it is also impractical. My attitude is if you have healthy soil fed with organic feeds and lots of organic matter like compost or mulch, your plants will be more healthy and resilient to diseases and pest attacks.
Of course nothing is 100% bulletproof and there are other reasons why plants can be affected like weather patters and unsuitable growing position/conditions etc.
So the bigger question is not if you should rotate crops, but if you should take care of the soil microbiome. And the answer is definitely YES!
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