Considerations to Integrate Biologicals Into Your Rotation

Brooks Reid considers himself a farmer who pushes the limits and thinks outside the box on his farm in Brunswick, Missouri. Biologicals have found a place in his corn and soybean rotation. “Biologicals interest me because they aid in fertilizer uptake,” the central Missouri grower said. “I believe that’s the key to increased yield.”

In a 2024 survey conducted by the Stratovation Group consulting company, “Ag Biologicals: Revisiting Farmer Value, Perception, and Potential,” 45% of all row crop producers say they purchase or use biological products. That is up 8 percentage points from the group’s 2022 survey. 

Despite the upward trend, confusion still exists about how and when biologicals work best and how to fit them into crop management plans.

What Are Biologicals?

Understanding the types of biologicals and what they do can help farmers better understand where to apply products, said Anne Runkel, vice president of research and development at Mosaic. Runkel defined biologicals as naturally occurring or naturally inspired compounds, extracts, or living organisms. The most commonly used products can be classified as biostimulants and nutrient enhancers.  

“Biostimulants are activating the plant in some way; they provide some kind of signal or activation of normal plant processes to be most efficient,” Runkel said. “Nutrient enhancers are involved in making nutrients already in the soil available and increasing uptake.”

What Environmental Conditions Are Necessary? 

Biologicals compete in the soil biome by introducing beneficial microorganisms that enhance nutrient availability and stimulate beneficial microbe activity. Environment plays a key role. 

“Biology doesn’t look the same everywhere. Soil type, previous crop, weather are all factors,” said Ron Calhoun, senior marketing manager of Loveland Products Plant Nutrition. “It’s important to understand that biology isn’t going to work the same as chemistry.”

“We’re always trying things to see how they work in our environment,” Reid said. “There’s a lot of components that go into the living, breathing part of our soil and in producing a crop. They’re the little guys doing the heavy lifting while no one is looking.”

With biologicals, there will be variation from year to year, so looking at the win rate over multiple trials and seasons can help understand a product’s effectiveness, Calhoun explained. “Trust, but verify,” he said. 

“In 2024, many regions in the central part of the country experienced substantial rainfall and moved nitrogen out of the root zone,” Calhoun said. “In these circumstances, it’s more likely for a biological N supplement to show a benefit. Conversely, in ideal conditions, the success might not be as noticeable.”

How Can I Measure Success?

Calhoun said when beginning a new practice, having a measurable outcome is important. “If you only look for results after the fact, you might end up convincing yourself that it worked,” Calhoun said. “It’s more effective to identify what success looks like before your trial or side-by-side, so you can either confirm or reject that hypothesis later.”

Reid has found that tissue sampling adds value, giving him a more complete picture when weather conditions may be limiting. “Maybe there was a response to the product but it didn’t follow through to yield because something else became limiting,” he said. “Don’t just drive by the field at 60 mph. Stop, get out, take a shovel. Look at a leaf, look at the soil. Become a student of your crop and don’t be afraid to ask questions.”

Can Biologicals Replace Fertilizer? 

Although a plant doesn’t use all the fertilizer applied in a given season, Runkel doesn’t recommend reducing fertilizer rates when using biological products. “Biologicals help with nutrient utilization from what fertilizer is applied and what fertilizer is available in the soil already to make sure it’s as efficient as it can be,” she said. 

“Adding more fertilizer to get more yield doesn’t always translate to yield or ROI,” Reid noted. “Sometimes, you can actually get more with less. That’s what we’re managing and tracking is how to do a better job with our inputs.”

What Are Suggestions for Trying a New Biological? 

Calhoun highlighted the importance of asking questions. “University Extension can’t evaluate every product that’s out there,” he said. “You need to be an informed consumer.” 

When considering biological products, Calhoun recommends working with a trusted adviser to help sift through all the options. “Ask for data that demonstrates that it performs as advertised, and is effective in a real-world conditions,” he said.

When thinking about where to place a biological product, Calhoun said, consider the following: “What are your goals? Do you have fields that typically underperform? Which fields are keeping you up at night? By identifying those problematic areas, we may be able to make a significant impact.”

Runkel recommends considering how a product fits into current farming practices. “Farmers are very busy people; it can be tough to manage all the different things that need to be done,” she said. “It’s important to find solutions that work with existing agronomic practices and fit well within their program.”