Some claim fertilizer is a dangerous “fixation” that wrecks the environment. And yet, global population is expected to near 10 billion people by 2050—that’s 2 billion more mouths to feed—so humans will likely need a lot more. Can humankind innovate its way out of a potential disaster?

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People have used human and animal waste to help crops grow for thousands of years. Manure is rich in nitrogen, phosphorus, and potassium, critical nutrients for strong crops. Yet this “natural” fertilizer has inherent limitations, and eventually a problem arose. The population started growing faster than the food supply needed to support it. That meant one of two things had to happen: Either fewer people or more food. But more food requires more fertilizer, and on this front nature let humanity down. In 1798, Thomas Malthus summarized the dilemma: “The power of population is indefinitely greater than the power in the Earth to produce subsistence for man.”

In some sense, Malthus was right. The Earth, by itself, does not produce enough useable resources to support rapid population growth. It provides plenty of raw materials, but raw materials are different than useable resources. Oil, for instance, was an essentially useless raw material until people figured out how to convert it into useable energy—kerosene for lamps, then gasoline for vehicles.

But Malthus failed to appreciate the people’s ability to make the Earth more productive than nature alone would allow. Enter Carl Bosch and Fritz Haber. In 1908, these two German scientists discovered how to mass-produce nitrogen fertilizer using natural gas, replacing animal manure as the primary method of delivering nutrients to crops. This discovery, known as the Haber-Bosch process, applied human ingenuity to convert natural gas, a raw material, into a useable resource, nitrogen fertilizer.

“It’s hard to think of many things in our life that are more underappreciated than the advent of synthetic fertilizer,” Jayson Lusk, an agricultural economist at Oklahoma State University and the author of Unnaturally Delicious, told me. “Wealth and opportunity, freedom from famine, and the ability to go through life without having to worry about where our next meal comes from, we can credit to the discovery of nitrogen fertilizer.”

Still, human-made fertilizer didn’t “take off” until after World War II, according to the Canadian environmental scientist Vaclav Smil. Global fertilizer production rose 220 percent between 1920 and 1940 but exploded by 3,000 percent from 1940 to today. In the mid-20th century, many experts maintained the Malthusian view that population growth would outpace food production and millions of people would starve to death. In his 1968 book, The Population Bomb, for example, the American biologist Paul Ehrlich lamented: “The battle to feed all of humanity is over.”