Fertilizer a Sri Lankan tragedy
Mar 25, 2022
This is a story about Sri Lanka's history and dependence on fertilizer.

Why do we use fertilizer in the first place? In this piece, we take you from Robert Malthus’s influential fears of famine from the 17th century, to the invention of fertilizer, to the impact it had on both global agriculture and our little colonised state.

Why do we use fertilizer?

But wait, weren’t we self-reliant at X point in history?

Meanwhile, in the Global South...

The Ghost of Malthus

The data for this piece


Many of you would have heard of the organic farming debacle by now, and how the government pretty much banned chemical fertiliser overnight. Apart from local troubles, it also created international headlines like how our ‘plunge to organic farming brought disaster’, and how, “In Sri Lanka, Organic Farming Went Catastrophically Wrong”.

But first, here's a recap of what went down:

Faced with a deepening economic and humanitarian crisis, Sri Lanka called off an ill-conceived national experiment in organic agriculture this winter. Sri Lankan President Gotabaya Rajapaksa promised in his 2019 election campaign to transition the country’s farmers to organic agriculture over a period of 10 years. Last April, Rajapaksa’s government made good on that promise, imposing a nationwide ban on the importation and use of synthetic fertilizers and pesticides and ordering the country’s 2 million farmers to go organic.

The result was brutal and swift. Against claims that organic methods can produce comparable yields to conventional farming, domestic rice production fell 20 percent in just the first six months. Sri Lanka, long self-sufficient in rice production, has been forced to import $450 million worth of rice even as domestic prices for this staple of the national diet surged by around 50 percent__. The ban also devastated the nation’s tea crop, its primary export and source of foreign exchange__.

The “botched scheme to establish the world’s first 100% organic farming nation”, as Al-Jazeera describes it, has led to $200 million being paid out to farmers by the government, in the middle of an economic crisis.

Let’s take a step back and examine the problem from the basics.

Why do we use fertilizer?

To understand fertilizer, let’s start with a bit of historical perspective.

In the late 17th century, the English cleric Thomas Robert Malthus wrote An Essay on the Principle of Population [1]. It primarily speculated on two things: 1) A growing population rate contributes to a rising supply of labor and inevitably lowers wages.

  1. A growing population will eventually outstrip the ability of a society to produce resources like food. Technological gains will lead to massive population growth. Massive population growth leads to further strain on the food supply, which fails. Cue famine, war people dying off en masse. This is what’s known as a Malthusian catastrophe.

Image: chart showing a Malthusian catastrophe, showing an exponential increase in population against a finite production of resources.

It’s hard to overestimate how influential this thinking was. Malthus’s book led to the Census Act of 1800, from which we derive the practice of having a population census every 10 years — this is practically the reason we have state statistics in the first place. It even contributed to Darwin’s thinking on evolution. Many of the seeds of thought around family planning ultimately derive from Malthusian origins. [2]

And indeed, it must have seemed like an inevitability. The old ways of producing food were sustainable, but hugely labor-intensive, and populations in the world were growing. Legumes can fix nitrogen into the soil, but the world is not covered in peas and beans, and waiting for the natural process to happen must have seemed like a luxury when the need was for regular crops this year, next year, and the year after that, all while populations moved into different types of jobs.

And then the World Wars happened. In particular, we arrive at the Haber-Bosch process, discovered by German-Jewish scientist Fritz Haber and scaled by German chemist Carl Bosch. The Haber-Bosch process uses nitrogen from the air to produce ammonia. This was wonderful news for the production of explosives, but as it happens, this is how we get synthetic, nitrogen-based fertilizers.

And thus residue of decades of arms and ammunition development were transformed to act as the basis of what be a revolution in agriculture: fertilizers. And it throws a complete spanner in the works of Malthusian thinking.

Image from Sid Meier’s Civilization VI, from

It helps if you think of it in terms of a videogame, like the Civilization franchise. At some point, there’s a limited number of land you can build farms on. Meanwhile, you need to grow stuff: to feed people, to supply the international market that you’ve stuck this country into.

What do you do? You look for ways to maximize yield per acre. You go and buy some fertilizer. You tell farmers about this thing that can make them so much more productive. You introduce incentives so that they can access it for cheaper. Excellent! Now you can feed yourself.

So powerful was this new stuff that Our World in Data notes that “it may be the case that the existence of every second person reading this attributes back to their 20th century innovation.” Indeed, much of the world is heavily reliant on such fertilizer, as this 2017 chart shows.

Image from Our World in Data / fertilizers, showing the nitrogen fertilizer use per hectare worldwide.

Now, populations grow. Export yields increase. That fertilizer now becomes a part of your very existence.

But wait, weren’t we self-reliant at X point in history?

Politicians invoke a time when Sri Lanka was a self-sufficient country in the production of rice. In fact, even that Foreign Policy article cited above says that Sri Lanka was “long self-sufficient in rice production.”

In general, Sri Lanka has not been agriculturally self-sufficient for a long time. Here’s milled rice imports data for Sri Lanka from the United States Department of Agriculture [5].

Even with fertiliser, we have not been able to reach the claims of mytho-historical self-sufficient.

A common mythos in the conversation is that under Parakramabahu the Great, Sri Lanka managed to feed a population of over 21 million people and feed itself.

That story is riddled with issues, as we explored in this piece that looked critically at the root of the myth of Sri Lanka as an agriculturally self-sufficient nation. We looked at the common way of estimating the population of the Polonnaruwa kingdom — by reverse-engineering claims of army sizes in historical texts — and pointed out that those claims simply do not intersect with what we know of world history. There is no reliable evidence that tells us that we can support a modern Sri Lankan population by suddenly running back to the ways of the ancients, much less interact with a modern global economy.

Meanwhile, in the Global South...

In countries like Sri Lanka, colonization and its estate agriculture added a second burden. Countries in this model were resource engines for the vast network of an empire. This led to sustainable-but-slow traditional subsistence farming being turned into export-based commercial plantation agriculture, with tremendous incentive to maximize output. So, spurred by the potential all-round gains, these chemicals were exported to the Global South under the banner of the ‘Green Revolution’ [3].

Let’s dig into this effect a bit more. Instead of adding fertilizer to the old methods to boost per-acre yields, countries like Sri Lanka began running a lot of monocultures in our agriculture — cutting down vast amounts of forest and turn them into specialised, one-crop plantations. [4]

As a result, tea estates grow tea. Rice fields grow rice. And so on. Little to no crop rotation takes place, and there is certainly no expectation of the natural processes fertilising the soil. Instead, what we have is the trinity of weedicides, pesticides, and inorganic fertilizers.

Photo of a tea plantation near Kandy, by Mal B on Flickr.

This leads to loss of natural soil fertility and soil revision. What happens when soil erosion kicks in and natural yields drop? Well, now you have no choice but to use large amounts of fertilizer to maintain production.

Dr. Vandana Shiva, environmentalist and scholar, notes how this ‘militarised model of agriculture’ is fundamentally unsustainable. Now this is, of course, in stark contrast to the optimism of Our World in Data, the mathematical argument for how fertilisers are good, and how every second person alive owes their existence to this invention.

However, two things can be true at the same time. It is true that fertilizers enabled an agricultural revolution that sent the human race’s food production capabilities skyrocketing, allowing us to not just live, but to regularly take in caloric amounts that would made us look like gods to our ancestors.

It is also true that the implementation of these policies, brought to the Global South under the interests of colonization and resource extraction, left us in a bind. We have close to 22 million people in Sri Lanka now, and they need to eat. We also have to deal with a brutal colonial hangover: monoculture crops like tea that destroy the soil and cannot exist without fertilizer, on which we have built an economy.

The Ghost of Malthus

What do we do in a situation like this?

If this piece has made anything clear, it should be that fertilizer is not to blame. As Our World in Data so clearly points out, it has been a boon to the entire world at large.

Instead, our problem is the agricultural system we’ve built (or failed to rebuild): a system reliant on both ecological destruction, monoculture crops, food imports and fertilizer imports to keep our population fed at reasonable prices. Sri Lankan agriculture is built on the corpse of Ceylon, a single vassal unit kept intentionally reliant on a vast empire to function.

There are two ways this could have gone.

One involves reforms towards more local, sustainable agriculture. Many have spent years pointing out that more sustainable, old-school methods can be brought back to reduce our dependence on this particular model.

Given Sri Lanka’s economic crisis - decades in the making — and our foreign debt issues (which we’ve covered) — it should be fairly apparent that this system needs to be reformed. We’ve known for decades now that the system is unsustainable.

But it should be clear this should be done with caution. Malthus may be only a spectre on the world average chart, but here, we have to tread carefully to avoid him.

In the 1980’s, much attention was given to what’s called ‘integrated soil fertility management’ - shifting away from purely pumping soil up with fertilisers, to enriching the soil with organic composting techniques. As Dandeniya and Cauci note in their study of composting in Sri Lanka, this led to an uptick in research on composting techniques, compost application rates, and benefits of applying compost. However, they found that organic fertiliser application didn’t really become popular; farmers found it difficult to obtain materials, and had issues with timing compost production in a way that could let them meet demand. [5]

So these ideas still need extensive field testing as historical claims alone are not enough. Imagine an acre of rice that requires the maintenance of an acre of forest nearby to sustain and fertilize it, or a crop rotation schedule that means that one year it will provide rice, the next year another crop. Which crops do we prioritise? What do we import? How much? What do we allocate fertilizer to under this new scheme? And how do we feed people while these changes happen? If we aren’t exporting tea, coconut and rubber, then what do we build our economy around? How do we make the switch? What stores of food do we have while we make a switch?

Rhetoric is easy. Feeding 21.9 million people is harder.

There is another option: go harder on fertilizers. This 2016 paper pointed out that improvements in rice production can feed 25.3 million Sri Lankans (compared to a projected population of 23.8 million people) by 2050. However, to achieve this growth, consumptive water use and nitrogen fertilizer application may need to increase by as much as 69 and 23%, respectively. This assessment demonstrates that targets for maintaining self-sufficiency should better incorporate avenues for improving resource use efficiency.

This is the second option: add more fuel to the fire, so to speak. This is the path that Sri Lanka has been on for a while, and the rice data above shows some of the results: a slow drop in imports.

However, this doesn’t change the damage already done to the soil. Decades of poor systems still need to be rolled back, and, in cases like tea, potentially even eradicated altogether. It requires hard decisions: like, will we be okay with not exporting tea and coconut, if it means we can grow enough to feed ourselves?

These were (roughly) the two sane options available to us before the organic fertilizer debacle.

This is a very simple explanation of how the board is set. The actual math is far more complex than I can lay out here. Regardless of which kind of change we champion, it cannot be done overnight; this is decades-long restructuring, the kind of change that can only happen with a serious commitment to long-termism and the political patience required to make steady incremental changes towards a well-defined target.

In the next piece in this series, we’ll examine how, over the years, various governments attempted to move the pieces around - and the impacts of the latest move; the sudden, unanticipated, nationwide shift into organic farming, and the fallout that followed.

The data for this piece

Sri Lanka labor force survey.pdf 5060255


[1] Malthus, T. R. (1872). An Essay on the Principle of Population.

[2] Malthusian thinking didn’t magically die off: it continued well into the twentieth century. In 1968, The Population Bomb by the Stanford biologist Paul Ehrlich became a bestseller. It was built on a distinctly Malthusian idea - that the humanity’s population growth was outpacing its ability to feed itself. As this beautiful video by TED-Ed illustrates, the book became enormously influential.

Except with economist Julian Simon, who critiqued The Population Bomb, accusing Ehrlich (and Malthus before him) of playing with theoretical numbers without understanding the actual data. This devolved into a massive academic feud, culminating in both opponents agreeing to a $1,000 bet on the fate of humanity - a bet that Ehrlich ultimately lost. That, more than anything, might have been the final nail in Malthus’s coffin.

[3] Mapa, R. B. (2003). Sustainable soil management in the 21st century. Tropical Agricultural Research and Extension6, 44-48.

[4] Unfortunately, this combination of fertilizers and export-oriented monoculture crops degrades the soil even further. Consider this entry from the Oxford Research Encyclopaedia by researchers Mukhopadhyay & Mondal, who studied tea:

Tea is produced in almost all of the continents on Earth, and the total area under cultivation is still growing. Hence, in order to make enough land available for tea cultivation, vast areas are being annexed throughout the world, and that obviously entails deforestation, which has numerous negative effects on ecosystems. The most hazardous environmental impact of tea production is the alteration of habitat (Clay, 2003__). According to a number of reports, forests are still being uprooted in East Africa to facilitate new plantations (McLennan, 2011__). Nevertheless, tea cultivation is not the solitary cause of deforestation. Around 70% of the terrestrial plants and animals live in the forest ecosystem, so massive alteration of natural habitats forces the flora and the fauna of that area to struggle to live, and this can culminate in loss of biodiversity if the species do not survive. Simultaneously, trees also play a key role in stopping global warming, as they absorb greenhouse gases. Thus, the felling of trees en masse for tea planting has environmental implications. Furthermore, with the elimination of trees, accumulation of leaf litter on the soil surface shrinks, resulting in the concurrent reduction of organic matter content in the soil and the subsequent hampering of the soil’s water-holding capacity. During heavy downpours, soil is subjected to erosion, followed by siltation of riverbeds and adjacent drains, which ultimately threatens irrigation schemes.

In order to achieve higher productivity, estates are kept weed free by weeding and applying scrapers. Manual weeding using scrapers resulted in severe soil loss of about 30 cm of topsoil per hectare by erosion in Sri Lanka (Ekanayake, 1994__). This loss translates into average soil erosion of 40 metric tonnes/ha/yr (Krishnarajah, 1985__).

[5] I used the USDA because while this data ultimately originates from Sri Lankan government authorities, it’s locked in PDFs that require an enormous amount of work to make usable in tabular form. The USDA data is far more convenient for this type of brief overview. Looking through USDA reports, they rely on organizations like the Sri Lankan Department of Census and Statistics and the Sri Lankan Department of Agriculture, with the US Foreign Agricultural Service (FAS) Colombo branch (operating out of New Delhi) providing synthesis and reports.

[6] Dandeniya, W. S., & Caucci, S. (2020). Composting in Sri Lanka: policies, practices, challenges, and emerging concerns. In Organic waste composting through nexus thinking (pp. 61-89). Springer, Cham.