By Jennie Kramer, Contributing Writer

Organic food is more than a trend for a growing number of farmers across the country. According to the USDA Economic Research Service, the market is worth an estimated $52 billion in 2021, an increase from $26.9 billion in 2010.

For those willing to make the transition, chemical-free crop production has the potential for profitable and sustainable growth. But what does organic no-till look like? Is it even possible?

Lea Vereecke, an organic consultant and regional manager at Rodale Institute, grew up on a conventionally managed small-grains operation in France. Following her college graduation, she worked at the University of Wisconsin-Madison, overseeing research related to sustainable agriculture. Currently she provides technical assistance to producers, answering these questions and more, and learning alongside those who share her passion for conservation agriculture.

Much of Vereecke’s research addresses the production of corn and soybeans and examines chemical-free systems where planting is done into a cover that has been roller crimped or cut. Ideally, the terminated cover provides both fertilizer and weed control for the crop. Vereecke shares her observations, discussing the essential elements of an organic no-till system.

Cover Crop Considerations

Seeding rate: Planting to produce adequate biomass is critical, so Vereecke advises planting in seeds per acre.

“Many seed providers can provide you with a seed-per-pound seed count. So 1.5 million seeds per acre, depending on your seed count, can mean anywhere from 68 to 100 pounds. That’s a huge difference. So, I highly encourage you to look at the seeds per acre,” she says.

“It seems like you can aim for 1.5 million, roughly a hundred pounds, and still get the biomass you need to grow a successful organic soybean crop in that rolled-down rye.”

The number of seeds per pound varies significantly. Consequently, planting in pounds per acre can result in inconsistent biomass. Vereecke recommends planting in seeds per acre for a more uniform and functional stand. 

Variety: Vereecke cautions against getting stuck on a specific variety of rye. Instead, she focuses on creating conditions that will produce a stand of 8,000 pounds of biomass per acre without applying herbicides.

While there are minor differences between varieties, “what I will tell you is you can use any of those and it’s going to work. There is not a difference big enough to justify going for one or the other.”

Planting date: Before October 1.

Cover Crops Need a Boost?

Fertilizer: Vereecke is often asked if it’s necessary to fertilize a cover crop. She recommends having about 60 units of nitrogen available in the fall as a fertilizer, but also as an investment in weed control.

“That can come from your organic matter, that can come from a previous cover crop, from crop residue from your previous crop,” she says.

Tillage: Transitioning to regenerative crop production isn’t always a linear process. Sometimes, Vereecke explains, minor concessions are necessary.

“What I’ve seen on farms is drilling or broadcast followed by shallow incorporation with a vertical-tillage tool is the best way to establish a beautiful, even stand of rye,” she says, explaining the light tillage allows growers to leave the field undisturbed for a year or more. And it’s an effective way to level fields following corn production, Vereecke notes.

Stand Assessment: “The cover crop is going to be your weed control for the entire season,” says Vereecke. To act as both fertilizer and a weed barrier, the stand must be substantial enough to cover exposed soil. How do you know if your stand will do the job? To answer this, it’s necessary to know a little about the biology behind cereal rye.

Rye needs to vernalize, to be exposed to a period of cold temperatures as a small plant, and it will only shoot stems when it receives 14 hours of daylight and temperatures of 40-50 degrees. If you do a stand assessment, Vereecke recommends doing it in the tillering phase.

“You don’t want to see the rye in the further stages. If you go in a field in May, the rye is going to look good no matter what. I think early to mid-April is a really good time to go ahead and do your rye stand assessment. The snow is melted, and the rye is not elongating yet.”

Vereecke has a rule of thumb she borrowed from a Wisconsin soybean farmer. When doing stand assessment: 80% or more cover, it’s a go, no matter how many weeds are in with the rye. But at 50-80% cover it’s only a go if there are no weeds. If it’s less than 50%, she suggests working in the rye and finding a new approach because there won’t be enough biomass to effectively control weeds.

For improved accuracy, Vereecke recommends the Canopeo application. The tool uses a photo image to estimate the green canopy, the percentage of soil covered. Vereecke cautions, “When you’re taking the photo for the app, the camera angle is critical. The photo has to be taken facing straight down, no angle on the phone when you’re taking your photo.”

Rules for Crimping

Crimping: Much of Vereecke’s research focuses on what she terms “crimpability.” Which crops can be crimped? When is the ideal time to crimp? With rye, Vereecke stresses the importance of waiting for anthesis, or flowering.

“Anthesis can extend for 4 to 5 days, and you want to wait until the end of it. It’s hard to do,” Vereecke says. “One way to do it, that’s going to be better for germination, is to wait until the very end of anthesis. The rye is going to crimp very easily at that point. I know in conventional bare-dirt planting, the planting date of the soybean is critical to the yield. In this system, you’re better off waiting for the very end of anthesis rather than going too early.”

Considerations for Soybeans

Seeding: Vereecke recommends a 185,000 seeds per acre minimum for an organic system. Planting depth may be as much as 2.5 inches, but a depth of 0.50 inches may be enough for a thick layer of rye protecting the seed and acting as additional soil. Vereecke emphasizes the importance of moisture when planting soybeans.

“You want that soybean to pop right out of the ground. If there is no moisture, that’s not going to happen,” she cautions.

While a variety of planter options exist, Vereecke recommends keeping it simple. “We tried different down pressures. We either had a fluted coulter or no coulter. We tried four different closing wheels — none of those made any significant difference in the yield,” she says.

“Don’t invest in a whole lot of different toys and tools that can be put on your planter. A good planter is a heavy planter so it can counteract the pressure it has to put on the ground. That’s all you need.”

The averages of several studies from 2019-2021 showed attachment choices make little difference in soybean yields. A consistent seed-per-acre rate and a planter that is heavy enough to counteract the pressure it’s putting into the ground are key elements of success.  

[Organic Chart 2]

Fertilizer: What about starter fertilizer? In Vereecke’s trials, 25 pounds/acre were added at planting. “We compared weed pressure, soybean biomass, and yield. No difference in soybean yields. So, the starter did not work in that system.” Vereecke is quick to point out the difference in weed biomass. The side-dressed pelletized poultry manure and feather meal became available too late for the crop to use but were ideally timed for weed uptake.

Precipitation: Vereecke identifies the critical period as May 15 to June 15 when planting corn and soybeans.

“Usually if a drought occurs right at planting time, that’s a huge issue. If the drought occurs later in the season, the rye keeps the moisture in. If the drought is past June 15, if the soybeans are planted and established, then it’s going to play in your favor to have no-till in a drought,” she says.

“If the drought occurs at planting, it’s going to be a disaster because the rye takes some time to die, and it draws a lot of moisture out of the ground before you plant the soybeans. So that’s why the planting window and the rainfall during that window are critical in that system. It’s critical in any system, right?”

Soil Temperature: A canopy can lower soil temperature, benefiting soil microbes, but potentially delaying soybean germination. “Unfortunately, the cooler ground is not playing in favor of this system,” says Vereecke.

She believes this may account for the slight difference between no-till and tilled soybean yields. Says Vereecke, “Definitely pros and cons all over the place for this system.”

Planting Green: Growers often wonder if soybeans can be planted before crimping to give them a head start. Vereecke recommends planting no fewer than 15 days before crimping. Any less, she cautions, and growers risk killing the plant.

On the other end, how big can the soybean be? Here, Vereecke recommends crimping no later than the V1 stage, with VC to V1 being the ideal time to terminate. Vereecke cautions northern growers against planting early, as cooler, moister soil can cause rotting and lower yields.

Moving south, the practice becomes more feasible. “In our research, what we saw with early plants in the tilled system, we get a 3.75-bushel increase. In the no-till, we get a 5.75-bushel decrease,” she says.

An expense breakdown of organic till and no-till soybeans shows a marginal benefit associated with a tillage system. At present, the primary advantages of no-till are improvement in soil health and overall ecology on the farm. 

Economics: Vereecke used custom rates to measure the economic results of an organic no-till program. She assumed a high-speed disc pass, drill the rye, and seed cost of the rye.

The following year, a return with the roller-crimper (rotary hoe rate was used as a stand-in for crimper rate), plant soybeans, cost of soybeans, and a pass with a weed zapper (only if rye biomass isn’t enough), and soybean harvest. Vereecke acknowledges that the system isn’t true no-till.

“Reducing tillage is important to me,” she acknowledges, “But with the 100% no-till organic system, we’re not there yet. We just haven’t made it there.”

The numbers show that, in the organic system, no-till has not caught up to organic tillage. “I think we all agree here that we’re deciding that it’s okay for us to have a little bit of a lower return because we’re improving our soil health dramatically compared to the system where we’re cultivating quite a lot.

“I’m willing to pay that cost to improve soil health and feel better about what I’m doing on my farm.”

For growers who aren’t quite ready to go organic, Vereecke says they can cut costs by using a crimper with herbicides instead of herbicides alone.

Tips for Corn

Vereecke admits that organic no-till corn can be a challenging system and researchers are still looking for answers to some challenges.

“Anything I’ve tried, anything I’ve seen farmers try, has been very complicated regarding results for the yield of the corn.” Nevertheless, she shares her insights and suggestions to help producers improve their results.

A 2019-2022 study of organic no-till corn returned disappointing yields compared to those of organic-tilled corn. Vereecke believes these numbers may improve as advancements are made in planter technology and corn genetics.

Timing: Corn has an earlier planting date than soybeans, but you need the cover crop to be flowering, in anthesis, to properly crimp it. Plant breeding might improve this, Vereecke hypothesizes, or improvements to the machinery used for crimping.

Annual cover crop: Vereecke reports mixed results for trials of annual cover crops. Crimping wheat didn’t work well. Hairy vetch crimps well but flowers too late. Crimson and Balansa clover didn’t return enough data. Peas and chickling vetch didn’t crimp well. Crimping twice may be necessary in some cases. But Vereecke cautions, the more mechanical passes you make, the greater the risk of damaging your growing crop.

Perennial covers: Perennial covers require additional management. “Perennial covers are a beast,” quips Vereecke. “They have massive tap roots. Beating up their above-ground biomass, you’re going to have to do that a lot for the cover to die.” On a positive note, she states, “You’re not constrained by the flowering time. It doesn’t matter when they flower; you’re just going to keep mowing, cutting, flaming or rolling them.”

Vereecke tested red clover as a cover crop, sowing it with a small grain and waiting a year before planting into it. Her team tried several management approaches to ensure the corn had an advantage.

“We tried undercutting the clover with a high-residue cultivator. We do that before planting. We’ve tried flaming. Flaming didn’t make much difference at all. We’ve tried managing it with an inner-row crimper and a high-residue cultivator,” she notes.

“The only thing that made a difference,” according to Vereecke, “was undercutting before planting our corn. If you undercut, you’re cutting the roots of the clover, but the clover biomass stays on the ground to protect against the weeds.”

Soil conditions will influence the effectiveness of this approach. Termination of clover is easier when the soil is dry. Vereecke explains, “If you undercut the clover in dry conditions, it loses a lot of biomass. In wet weather, it’ll remain alive and keep growing.”

Planter setup: Disappointing corn yields inspired Vereecke to experiment with planter configurations. She admits the yields aren’t great yet. One tweak that helped was using a standard rubber closing wheel instead of an aftermarket closing wheel.

One of the reasons, she suspects, was weed pressure, as the aftermarket wheel was “spiky” and it poked holes in the cover and the ground, which favored weed pressure in the row.

Parting Thoughts

Change invites challenges, and transitioning to a chemical-free system is no exception. From biomass goals to planting dates, Vereecke’s guidelines pave the way for a smoother and more profitable adjustment.

Even so, variables like geography, weather, and crop rotations will require a degree of experimentation and innovation.

“A lot of what I represent has happened on a research station or has happened on one farm in one specific location. It will not work on your farm the same way, so each practice has to be taken and understood differently depending on where you are,” Vereecke says. “These are all things we’ve tried. Please, build on what we’ve done instead of starting from ground zero all over again.”

Challenges aside, some benefits of organic production, like decreased erosion, improved water retention, and the promise of premium prices, make the change worth considering. Others, like improved biodiversity and food security, extend beyond personal interests. In adopting these new, chemical-free practices, growers serve a higher purpose: fostering a healthier and more sustainable agricultural heritage for generations to come.