Study: Most Organic Crops Fall Short on Yields

Lower yields means feeding world organically requires clearing more land

A new study shows organic crops typically yield less than those raised with artificial fertilizers and pesticides.
A new study shows organic crops typically yield less than those raised with artificial fertilizers and pesticides.

Some organic crops produce nearly as much as conventional agriculture, but most still fall short, according to a new analysis.  

With a growing world population and limited land available to feed it, the study has implications for the debate on how to feed the world sustainably.

But some note there is more to sustainability than just crop yields.

Organic advocates say farming without artificial fertilizers and pesticides has less environmental impact.

But skeptics note organic farming generally produces less food per hectare. Lower yields means feeding the world organically would require clearing more land. Deforestation for agriculture is already a major contributor to climate change and biodiversity loss.

The new study in Nature looks at how big the gap is between conventional and organic yields.

More productive

The study combines 66 earlier yield studies. “Conventional yields are typically higher than organic yields, but with certain management practices, certain environmental conditions, and certain crop species this yield difference can be quite small,” says lead author and McGill University researcher Verena Seufert.

On average, organic crops produced 25 percent less than conventional.

Vegetables and cereal crops (maize and wheat, for example) performed worse: 33 and 26 percent, respectively. But organic fruits and other perennials nearly matched conventional yields. So did legume crops like soybeans that produce some of their own fertilizer.

The organic penalty was smaller on organic farms that relied on rainfall, which were 17 percent less productive, compared to irrigated farms, which fell behind by 35 percent.

“Under rainfed conditions where water supply varies depending on weather conditions, the organic soil can actually provide water better to the crops because it can capture and maintain this water for longer,” Seufert says.

Harder to manage

One area where organic farmers could improve, she says, is giving their crops enough nitrogen fertilizer. Those that received more nitrogen had smaller yield differences, she says.

But that’s harder to do organically with just manure and crop rotations, she says.

“In conventional agriculture, you just dump inorganic nitrogen fertilizer on the plants and they grow; while in organic agriculture, you need to manage the system. You need to manage the soil. You need to improve the soil quality,” Seufert says.

And besides fertilizers, farms that also used industry-standard best management practices for weeds and pests reached nearly 90 percent of conventional yields.

Land issue

If organic crops were given the right amount of nutrients and protected from weeds and pests, they could produce the same amount as conventional crops, says agronomist Ken Cassman at the University of Nebraska at Lincoln.

But he says that’s not the issue.  

“The problem is the land issue, if you’re talking global food security,” he says. “Because either you’ve got to have [a] longer [crop] rotation or you have to bring nutrients from outside the system somehow.”

Organic farmers rotate food crops with plants that fertilize the soil. But while fertilizer crops are growing, food crops are not. So food has to be grown somewhere else.

Or farmers fertilizer with manure. But it takes grazing land or crop land to feed the animals that make the manure.

The world’s food demand will grow by 70 percent by mid-century, according to the United Nations. Cassman says researchers need to figure out how to meet the demand on the same amount of land that farmers are using today.

“There really isn’t much good land left that’s not, for instance, rainforest, or wetlands, or grassland savannah, which are the last carbon-rich and biodiverse regions that we have,” he says.

Hybrid farming

“I think when people see these studies, their first reaction is, ‘Well, my goodness, organic farming can’t feed the world,’” says Washington State University soil scientist John Reganold. “Guess what? Conventional farming cannot sustainably feed the world.”

He says it takes a lot of energy to make artificial fertilizer, and experts say some key ingredients are running out.

And he adds that sustainability means more than just producing high yields, according to the U.S. National Academy of Sciences. The environment, social justice and economic viability are important, too.

He says organic and conventional systems are bookends - extremes at opposite ends of the spectrum. He says more and more, farming is becoming a hybrid of both.

The University of Nebraska's Ken Cassman says the arguments over ideology are a distraction.

“You don’t focus on whether organic is better or conventional is better,” he says. “You simply focus on the outcome.”

“In my personal food decisions, I have a mix," says study author Verena Seufert. "And I think we do have to have to have that on a larger scale.”

This forum has been closed.
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Russia’s Syria Involvement Raising Concerns in Europei
Luis Ramirez
October 02, 2015 4:45 PM
European nations are joining the United States in demanding that Russia stop targeting opposition groups other than the Islamic State militants as Russian warplanes continue to conduct raids in Syria. The demand came in a statement from Britain, France, Germany, Qatar, Saudi Arabia, Turkey and the United States Friday. VOA Europe correspondent Luis Ramirez reports.

Video Russia’s Syria Involvement Raising Concerns in Europe

European nations are joining the United States in demanding that Russia stop targeting opposition groups other than the Islamic State militants as Russian warplanes continue to conduct raids in Syria. The demand came in a statement from Britain, France, Germany, Qatar, Saudi Arabia, Turkey and the United States Friday. VOA Europe correspondent Luis Ramirez reports.

Video First Self-Driving Truck Debuts on European Highways

The first automated semi-trailer truck started its maiden voyage Friday, Oct. 2, on a European highway. The Daimler truck called 'Actros' is the first potentially mass-produced truck whose driver will be required only to monitor the situation, similar to the role of an airline captain while the plane is in autopilot mode. VOA’s George Putic reports.

Video Nano-tech Filter Cleans Dirty Water

Access to clean water is a problem for hundreds of millions of people around the world. Now, a scientist and chemical engineer in Tanzania (in East Africa) is working to change that by creating an innovative water filter that makes dirty water safe. VOA’s Deborah Block has the story.

Video Demand Rising for Organic Produce in Cambodia

In Cambodia, where rice has long been the main cash crop, farmers are being encouraged to turn to vegetables to satisfy the growing demand for locally produced organic farm products. Daniel de Carteret has more from Phnom Penh.

Video Migrant Influx Costs Europe, But Economy Could Benefit

The influx of hundreds of thousands of refugees and migrants is testing Europe’s ability to respond – especially in the poorer Balkan states. But some analysts argue that Europe will benefit by welcoming the huge numbers of young people – many of them well educated and willing to work. Henry Ridgwell reports from London.

Video Botanists Grow Furniture, with Pruning Shears

For something a bit out of the ordinary to furnish your home, why not consider wooden chairs, crafted by nature, with a little help from some British botanists with an eye for design. VOA’s Jessica Berman reports.

Video New Fabric Helps Fight Dust-Related Allergies

Many people around the world suffer from dust-related allergies, caused mainly by tiny mites that live in bed linen. Polish scientists report they have successfully tested a fabric that is impenetrable to the microscopic creatures. VOA’s George Putic has more.

Video Burkina Faso's Economy Deeply Affected by Political Turmoil

Political turmoil in Burkina Faso over the past year has taken a toll on the economy. The transitional government is reporting nearly $70 million in losses in the ten days that followed a short-lived coup by members of the presidential guard earlier this month. The crisis shut businesses and workers went on strike. With elections on the horizon, Emilie Iob reports on what a return to political stability can do for the country's economic recovery.

Video Fleeing Violence, Some Syrians Find Refuge in Irbil

As Syrians continue to flee their country’s unrest to seek new lives in safer places, VOA Persian Service reporter Shepol Abbassi visited Irbil, where a number Syrians have taken refuge. During the religious holidy of Eid al-Adha, the city largely shut down, as temperatures soared. Amy Katz narrates his report.

Video Nigeria’s Wecyclers Work for Reusable Future in Lagos

The streets and lagoons of Africa's largest city - Lagos, Nigeria - are often clogged with trash, almost none of which gets recycled. One company is trying to change that. Chris Stein reports for VOA from Lagos.

Video Sketch Artist Helps Catch Criminals, Gives a Face to Deceased

Police often face the problem of trying to find a crime suspect based on general descriptions that could fit hundreds of people in the vicinity of the crime. In these cases, an artist can use information from witnesses to sketch a likeness that police can show the public via newspapers and television. But, as VOA’s Greg Flakus reports from Houston, such sketches can also help bring back faces of the dead.

Video Thailand Set to Build China-like Internet Firewall

Thai authorities are planning to tighten control over the Internet, creating a single international access point so they can better monitor content. VOA Correspondent Steve Herman reports from Bangkok on what is being called Thailand’s own "Great Firewall."

Video Croatian Town’s War History Evokes Empathy for Migrants

As thousands of Afghanistan, Iraqi and Syrian migrants pass through Croatia, locals are reminded of their own experiences with war and refugees in the 1990s. VOA's Daniel Schearf reports from the town of Vukovar, where wartime scars still are visible today.

Video Long Drought Affecting California’s Sequoias

California is suffering under a historic four-year drought and scientists say even the state's famed sequoia trees are feeling the pain. The National Park Service has started detailed research to see how it can help the oldest living things on earth survive. VOA’s George Putic reports.

VOA Blogs