Our present practice of chemical based farming has caused great harm to the natural environment and to the human beings and other species. Due to the application of chemical fertilizers and toxic pesticides, the soil has become toxic and not only that, the toxins have found their way through the food chain into our stomach. Various kinds of diseases have afflicted humanity, as a result of this poisoning. And hence, the need for toxin-free, chemical-free sustainable methods of agriculture has become more pressing than ever before. The different aspects of agriculture are: Soil management, Water management, Seed management, Fertilizer management, Pest management, Disease control, Harvest management, Post-harvest management.
Natural farming and organic farming are two approaches to sustainable agriculture. Natural farming completely eliminates the need for human intervention and does not disturb nature in any way. Rather it requires the farmer to observe closely the functioning and dynamics of the local ecosystem, and mimicking Mother Nature’s principles, so that the ecosystem takes care of itself. There is no need for tilling the soil, applying fertilizers or pesticides, weeding or pruning. Organic farming, another approach to sustainable agriculture, is a self-sustained, self-reliant method of farming where the agricultural inputs of crop production and protection are of organic origin, such as bovine manure, compost, and fertilizers and pesticides made from naturally occurring substances (eg: panchagavya and jeevamrutham).
The main aim of organic agriculture is to grow food crops in a self-sustained environment, with minimal use of external inputs of crop production and protection, which are produced by the farmer within his farmland.
The general opinion is that organic farming leads to low yields in comparison to inorganic farming, and may even lead to failure of crops. Let us examine this closely. Organic farming is a complete science which has its own tested and proven techniques of crop management, formulations of fertilizers and pesticides, biological pest control, water management and disease control. While organic farming will not give immediate high yields and profit like inorganic agriculture, its continuous practice over 5–10 years actually increases the soil organic carbon content (SOC), which is the very basis of soil fertility. Soil, which is presently depleted and of low fertility, due to inorganic farming, increases in fertility over the years through the practice of organic farming. The food produced through organic farming is completely free from all toxins, and safe for consumption.
Organic farming benefits all our future generations and humanity in the long run. As the soil becomes richer and more fertile, organic farming has a positive impact on the natural environment. Since the fertilizers and pesticides are prepared from within the farmland, it is a self-reliant and self-sustaining system, that requires no purchase of any fertilizers or pesticides from external agents.
Also, since organic farming is a method of sustainable agriculture, it’s yield is also “sustained” in the long run. In inorganic farming, the yield keeps increasing with time, while depleting and damaging the soil, until a point when the soil becomes unfit for growing plants. While in organic farming, the yield initially increases with time, and then stabilizes to a constant level of crop yield, all the time increasing the soil organic carbon content.
The most important aspect of organic agriculture is the management of soil. Soil is generally perceived as inanimate matter. But no! It is very much alive; it is a living organism in its own right. In 1 gram of soil there are 1 billion bacteria and 1 million fungi.
It is the soil microorganisms that are responsible for decomposing and breaking down the manure we add into the soil, into nutrients that are needed for the plants. These biological processes in the soil is the distinguishing factor in organic farming, whereas in inorganic farming, plant nutrients are supplied as salts in the form of chemicals.
Organic carbon is the “blood of the soil”. Why is carbon important? Because it is the very basis of soil fertility. Soil Organic Carbon (SOC) is the main source of energy and nutrients for soil microorganisms. The organic matter in the soil, such as plant and animal residues, under the right conditions of soil temperature and moisture, undergo a process of degradation to form humus. It is this humus that is important for nutrient and water holding capacity of the soil. Humus does not build up in the soil in a short period of time. However, once it builds up, neither does it leave the soil quickly.
Only after 5 years of continuous organic farming, does the organic carbon content in the soil increase by as much as 0. 05 %. Hence living soil is composed of 25% air, 25% water, 45% minerals, clay, sand or silt and 5% dead and living plants and animals. Ideally the Carbon: Nitrogen ratio in the soil should be 10:1
The richness of soil is measured in terms of :
Density of micro-organisms present (Nun Uyirgal)
Organic carbon content (Karimai chathu)
Macronutrients- Nitrogen(thalai chathu), Phosphorus(mani chathu) and Potassium (Saambal chathu)
Micronutrients – Boron, Zinc, Manganese, Iron, Cobalt, Copper, Molybdenum and Chlorine
Manure and Compost
Now, to start an organic farm, a farmer must have his own source of water for irrigation and a continuous source of manure. The manure takes care of soil microbes that in turn provide nutrition for the plants. One cow is needed for one acre of land. Cow dung is an excellent source of manure. The products from cows are used for the preparation of panchagavya and jeevamrutham, which will be discussed later in the article. We also learnt how agricultural wastes such as plant and livestock wastes could be turned into valuable compost, which is a rich organic fertilizer for plants.
Generally, farmers dump all their farm wastes and manure into a large pit in the farm called, ’ Eru Kuzhi’ and leave it there untreated for a whole year. Even after a year, the decomposition process may not be complete and may only be partially decomposed. The scientists explained that instead of dumping wastes in a pit and leaving it to natural decomposition, the wastes and manure could be made to undergo a process of active and faster decomposition, through the science of composting, and turned into rich compost. Composting is a technology in itself! They explained the elaborate process of composting and the do’s and don’ts of it. The science behind vermicompost, using earthworms was discussed, and we learnt that it was superior to the normal method of composting. The finished vermicompost is richer in nutritional content. The farmers were encouraged to invest in rearing earthworms for vermicomposting.
The fully decomposed, finished compost is rich in Carbon, Nitrogen, Phosphorus, Potassium and most importantly, microorganisms. The compost needs to be added in appropriate amounts during the various stages in the life cycle of crops. We were warned that if, following the normal tendency of our minds, we added it in excess amounts hoping for huge yields, we would be in for huge disappointment!
One may ask, ‘The atmosphere contains 78% Nitrogen, why can’t the crops absorb it directly from the air?” The reason is that the crops can take in Nitrogen only in the form of nitrates, and not in the elemental form. Similarly, Phosphorus and Potassium are absorbed only in the phosphate and potassium oxide forms respectively. The fixation of Nitrogen from the atmosphere to the root of the plants in the form of nitrates is done by Nitrogen-fixing bacteria such as Rhizobium and Azospirillum. Phosphorus solubilizing bacteria such as Phosphobacteria and Pseudomonas, using their enzymes, release Phosphorus from insoluble compounds and make it available for uptake by plants. Potassium Solubilizers like Bacillus mucilaginosus release Potassium for the plants’ uptake through a similar process. These beneficial bacteria called biofertilizers, are prepared as pure cultures in the laboratory in controlled conditions and can be purchased by organic farmers.
Organic farming is all about “management”. There is no need to eradicate any organism in the environment. Each organism has its role to play. There is something called the ‘Economic Threshold Level’’; below this level of pest population, nature will control it and there is no need for human intervention. The predators, their natural enemies will keep them in check. Monitoring the level of pests on a day-to-day basis is very important. It is also important to know the various species of pests, their lifecycles and the stages of the crop’s lifecycle during which they attack the crop. If the threshold level is crossed, the pests can be kept in check using traps such as light traps and pheromone traps or spraying pesticides prepared using naturally occurring substances, available locally, such as Neem Seed Kernel Extract and 3G (Ginger, Green Chilly and Garlic). The farmer must plant the trees and plants, whose parts are used for pesticide preparation, and which are natural pest repellers, such as Cycas, Golden Shower and Neem, surrounding the farm.
The farmer must select strong and healthy seeds for plantation, and dispose of wrinkled seeds, which have been affected by bacteria and fungi. Various methods of seed treatment, such as soaking the seeds in panchagavya and coating the seeds with bio-fertilizers were discussed. Self-reliance is primary; year after year, the seeds from the previous year’s harvest must be sowed during the current season, and must not be purchased from external agents.
Panchagavya And Jeevamrutham
The process of preparing panchagavya, an organic fertilizer and potent immunity booster, was discussed. It is prepared using five products of a cow: cow dung, cow urine, milk, ghee and curd, along with jaggery, coconut water, ripe bananas and water. It is used for foliar application. Jeevamrutham is prepared using cow dung, cow urine, jaggery, gram flour and soil. It is used for application to the root system.
There are stringent rules that must be observed by a farmer in order to receive organic certification for his farm. He must have his own source of irrigation on his farm, and not from external sources and canals. He needs to practice organic farming for a minimum of 3 years to be eligible for certification. After the first year of organic farming, the seeds from the first year’s harvest must be sowed for the second year. Various records of what inputs were used for farming must be maintained, and data logged regularly.
Applying the above techniques of organic farming on a smaller scale, such as in a home roof garden was also explained by the scientists. The roof of a medium sized house could serve as a “terrace farm” to grow and harvest fruits and vegetables used by the family for their everyday cooking. Thus even a family living in cities can grow their own food in the garden or on the terrace, and achieve self-reliance in food.
The drive home point was that organic farming is a science, and it requires the farmer to understand the functioning of the natural ecosystem and apply the agricultural inputs of crop production and protection in appropriate quantities, when needed and not in excess. The organic farm must be self-reliant, self-sustaining, with all inputs produced from within the farm. Organic farming is a sustainable method of agriculture, which in the long run, positively impacts human health and the environment.
All in all, it was an exciting, information packed workshop, giving a detailed overview of the techniques of organic agriculture.