It has been 6 years since we started organic farming in our land. We are very happy to announce that we have achieved an average of 5.75X increase in soil organic carbon at Vaanavil Farm & Food Forest, Vikramasingapuram, Tirunelveli District, Tamil Nadu. The results were very encouraging especially because the improvement was seen across the entire land.

Why did we do it?

1. Soil acts as a carbon sink if we implement the correct strategies in agriculture and sustain them over the long term. With soil performing the role of a carbon sink, the net emissions of agriculture can be reduced. *
2. The amount of carbon in the soil affects the water holding capacity of soil. So, the need for irrigating the soil reduces over long the term. Both the quantum and frequency of irrigation can be dialled down slowly as the effects of organic farming start kicking in
3. The leaching of macro and micro nutrients reduce with higher life in the soil. Agriculture is a resource intensive activity. Wasting the nutrients to run-off increases the amount of cost incurred.

Organic farming or Carbon Sequestration * alone is not a panacea to the modern problems of global heating, groundwater depletion, polar ice cap loss and many more. There is no strategy that can help reverse global heating. All we can do with a multi-pronged strategy is to slow down the progress of human-induced climate change.

How did we achieve this?

1. Reduction in tillage :
   • We practice minimum tillage for our annual crops of paddy and pulses – we do not conduct deep primary tillage like most farmers do. We only carry out secondary tillage using rotavator for producing the fine tilth needed for transplantation.
   • We have not tilled our coconut grove and multi-layer food forest for the last 6 years. In fact, we have fenced the land in such a way that a tractor cannot enter these plots. That might be the reason the increase in Organic carbon is even more stark in these two plots (5x and 7.5x) compared to paddy (3.5x).
2. Cover cropping :
   • This is an action exclusively for our annual crops.
   • 45 days prior to the paddy crop, we plant a mix of dhaincha (sesbania bispinosa), sanappai (crotalaria juncea) and ulundu (Vigna mungo). And then we plough it into the soil right before paddy transplantation, when they flower, to add all the biomass into the soil
3. Composting :
   • We compost all the cow dung, chicken coop, leaf litter, shredded coconut fronds, ash that we generate with firewood cooking. The only external input that we add to this compost is Bone meal because there are no sources of the macro nutrient Phosphorus available at the farm.
   • We recently got a shredder to convert all the waste wood that we generate at the farm into compostable carbon-rich material. One could argue that the shredding of coconut fronds using a petrol driven shredder itself is a carbon emitting activity. But when you compare it against the alternative of burning all the waste wood, the net result of the activity of composting even after using a shredder is known to be much superior because it captures at least some of the carbon in the soil.
   • Combustion of firewood by burning converts almost all of the carbon firewood into carbon dioxide, a greenhouse gas. Whereas gasification of firewood into charcoal, produces a lattice that is stable in soil for a long period of time. Biochar, as inoculated charcoal is now known, increases the fertility of soil by increasing the nutrient and water holding capacity. Owing to its surface area, it also houses a tremendous amount of microorganisms.
4. Mulching :
   • For all our perennial trees and crops in the coconut grove and multi-layer food-forest, we mulch generously every few months with our perennial biomass crops such as vettiver, lemongrass, glyiricidia, mexican sunflower, mexican tree spinach.
   • We also use crop waste such as coconut husk and hay to mulch.
   • Covering the compost with mulch also helps in ensure the life in the compost is preserved for longer.

What have we really achieved?

We have been driven by the ethics and philosophies of organic farming and permaculture so far. We haven’t let the cold hard raw numbers of economies of scale and productivity slow us down in realizing our objectives.  We have such a wide portfolio of diverse products that we do not even know how to calculate the composite productivity of the farm. How will we assign weights to each of the crops?

We haven’t yet calculated yields and productivity to draw comparisons with conventional agriculture. We do not think that it is fair to compare only yields of crops or productivity of land. There are many more objectives that land and agriculture fulfils for civilization than merely providing food. It is quite difficult to come up with a single metric to measure the combination of yield, carbon sequestration, life in soil. If you consider the factors of how organic farming has the capability to provide more meaningful employment, address wealth & income inequality, you will start to realize that it is almost impossible to come up with a lone metric to measure the benefits of organic farming over conventional industrial agriculture.

Having said that, we realize the need to be scientific in our approach as much as possible. We had tested right when we were starting our farm journey in 2018 and now in 2024 after we realized that the soil is much more alive than it was almost 5.75 years back. Our life-sustaining practices have ensured that the Organic Carbon, Nitrogen, Potassium and a few micro nutrients have reached levels which are ideal for growing crops. Barring the important macro nutrient of Phosphorus and the micro nutrient Boron, we seem to be in a comfortable position for most. Fixing Phosphorus is an important objective because its deficiency in soil can limit crop yields significantly. The recent inclusion of bonemeal and charcoal in our compost will improve the levels over the next couple of years.

We realize the importance of achieving higher productivity of crops in our land : once we fix the soil nutrient balance, we also have to choose the right open-pollinated varieties that yield higher. We need to improve strategies for pest and disease resistance.

The general consensus is that conversion to organic farming takes 3 years. This is for experienced farmers, in my opinion, who are comfortable with the mechanics of farming and know their way around the unique traits of crop varieties. For newcomers like us and some of you who are reading the blog, it might take even longer to achieve the desired level of crop yields to sustain the farm economics.

We have derisked the economics of farming from individual crop yields using a multi-pronged approach.

• diversifying our cropping and foraging strategy at the farm
• collectively selling produce by 20 farmers, thereby offering a greater variety to customers
• value-addition of produce
• selling direct to customer

Regards

Sudhakar

*There are limits to the amount of carbon each type of soil can hold. Once you hit that ceiling after a few years of practicing organic or regenerative farming, you will stop adding any more carbon to the soil.

The mathematics of the capability of soil to sequester carbon is what is often misused in carbon credit markets. The baseline is an arbitrary point of time from which the carbon sequestration is calculated.

We don’t plan to participate in the carbon credit market any time soon because we believe that most of humanity needs to participate in the carbon emission reduction mission. If we provide the opportunity to large companies to buy carbon credits, they might never take actions to reduce their emissions. The plan to reduce humanity’s overall emissions will not work if the large polluters continue to emit carbon dioxide, methane and nitrous oxide.