For Iowa farmer Mark Peterson, each new planting season brings with it a set of difficult choices. What type of crop should he seed? How much fertilizer should he apply? What farm practice should he use to produce the highest yield at harvest?

Each of these decisions impacts his bottom line. But with everything Peterson does, he keeps an eye on the future, seeking ways to ensure the long-term health of his farm.

While his land was in good shape when he began farming, “I want to make certain that when I leave this earth, the ground is in better shape than when I got it,” he says. “You have got to care about your grandkids and their generation.”

Peterson’s concern for the sustainability of his 500-acre farm, located near Stanton in southwest Iowa, is a prime reason he plants cool-season cover crops – including grains such as rye, oats and barley – in the fall and winter. Peterson became interested in these small grain cover crops through Practical Farmers of Iowa (PFI), a farmer-led organization cultivating support for economically and environmentally sound agricultural practices.

Mark and Melanie Peterson farm 500 acres near Stanton, Iowa.

For the last eight years, the Walton Family Foundation and PFI have partnered to help farmers adopt agricultural practices that promote conservation and boost their bottom line.

Corn and soybeans are the warm-season staples in Iowa. But cool-season cover crops and ‘third crops’ are becoming more popular. In 2016, more than 500,000 acres were sowed to cover crops in Iowa, a five-fold increase from 2012.

Cover crops improve the quality of the soil and the land’s ability to hold water, and reduce the amount of nutrients that wash into the Mississippi River basin.

Additionally, Iowa farmers planted nearly 100,000 acres to ‘third crops,’ which are grown to maturity and harvested for grain, providing an additional stream of income for farmers and many of the same environmental benefits.

These third crops are traditionally planted with nitrogen-producing alfalfa or red clover green manures, and can help farmers save on input costs.

The recent interest in cool-season plants marks an important shift toward more sustainable farming.

Forty years ago, most Midwestern farmers grew both warm and cool season crops.

Over time, changes in policy and technology led farmers to primarily grow corn and soybeans in the summer, while leaving the land bare the rest of the year. That contributed to a loss of nutrients such as nitrogen and phosphorous, which leak downstream.

The impacts in the Mississippi River basin, which produces more than 90% of all U.S. agricultural exports, have been significant. Since the late 1980s, nutrients in the river and Gulf of Mexico have grown steadily. Each summer the nutrients produce the Gulf’s ‘dead zone’ – an area of low oxygen deadly to marine life – that can reach 5,900 square miles, about the size of Connecticut.

The Walton Family Foundation believes the best way to improve the Mississippi River’s health is to work hand in hand with grassroots organizations to produce better environmental outcomes.

PFI stresses on-farm research and sharing of best practices among its 3,000-member network and with non-members, says Sarah Carlson, the group’s cover crop director.

“Our core work is helping farmers make those changes on the farm, and then getting them to tell their neighbors about it,” says Carlson.

The organization hosts field days, workshops and farmer ‘boot camps’ that bring together thousands of cover crop experts and non-experts to discuss issues including how agricultural practices affect water quality, soil health and weed management.

“I take my guidance from our farmers on what we should be working on as an organization, what we should be speaking about, and sharing,” Carlson says.

“We have farmers teach other farmers to make changes that can improve their balance sheet and protect the environment. Usually at the end of the day, the changes can do both.”

Peterson, who is board president at PFI, says farmers are more likely to grow small grain cover crops or third crops if their neighbors have seen benefits, such as increased soil fertility, improved weed control, lower input costs or new income opportunities.

“The work is being done by farmers on their farms, their way,” Peterson says.

Practical Farmers of Iowa also engages members to try new farm practices that reduce soil erosion and improve water quality.

“There are farmers who won’t plant cover crops because they are cash strapped,” Carlson says. “But we also hear from farmers who are using cover crops because they are cash strapped, and they need to save money on herbicide. Those cover crops are for weed control.”

The Gulf of Mexico’s dead zone is the “canary in the coal mine” for Midwestern farmers, Carlson says. “It is showing us that the way we are farming is really too leaky.”

Th Gulf’s problems can seem distant to farmers facing high costs and ever-changing commodity prices. That’s why conservation solutions must make economic sense.

Says Carlson: “Our work makes sense to farmers because it starts with farmers developing innovative solutions on the land to stay in business, while simultaneously reducing their farm’s negative impact on the Mississippi River.”

Peterson takes the long view when thinking about the benefits of changing the way he farms. “I probably can’t mess thing up so bad that my land will be in trouble while I’m still farming. It’s what’s left for the grandkids that I am concerned about.”