Rethinking soil data to improve fertilizer efficiency, yield

Soil sampling has long been standard practice in specialty crop production. But for many growers, the real challenge is not collecting the data — it’s knowing what to do with it.

“Growers take a soil sample, get the report back and say, ‘OK, we did it,’” said Dylan Rogers, a sales account manager for AgroLiquid. “But the real value is in understanding what that data is telling you over time.”

As input costs rise and environmental pressures increase, more growers are taking a closer look at how that data can guide decisions — particularly when it comes to refining fertilizer programs — rather than repeating the same approach year after year.

Looking beyond nutrient levels

One of the biggest challenges, Rogers said, is that soil tests are often interpreted at face value.

“It’s not just about how much of a nutrient is in the soil,” he said. “It’s about whether the tree can access it.”

A field may show adequate potassium levels, for example, but elevated sodium can interfere with uptake. In that case, the nutrient is present but not available to the crop.

“You might have good potassium levels, but if sodium is high, the tree is going to struggle to take that potassium up,” Rogers said. “It may take up sodium instead.”

That is why understanding how nutrients interact in the soil is just as important as knowing the numbers themselves. For AgroLiquid, that insight is foundational to how its fertility programs and product recommendations are developed for each grower.

Looking at trends over time can also reveal patterns that are easy to miss in a single report.

Turning data into action

AgroLiquid uses soil and tissue sampling together to guide product selection and application strategy at the field level. Rather than relying on a fixed program, growers can adjust rates, timing and inputs based on the data.

Tissue sampling helps confirm whether nutrients from fertilizer applications are actually reaching the plant throughout the season.

“That’s how you close the loop,” Rogers said. “You can track tissue levels during the year and make sure what you’re applying is actually getting into the tree.”

Field trial data from AgroLiquid trials suggests that approach can lead to lower overall fertilizer use without sacrificing yield.

In a 2024 mandarin tree trial comparing yield and gross income across two separate fertility programs, AgroLiquid’s program, which included products such as Pro-Germinator and Kalibrate, used less nitrogen and potassium while slightly growing yields but also increasing gross income significantly. The AgroLiquid program applied 154 pounds of nitrogen alongside 140 pounds of Kalibrate and 90 pounds of Pro-Germinator per acre, respectively, compared to 180 pounds of nitrogen, 134 pounds of 10-34-0 and 160 pounds of potassium thiosulfate in a common conventional program.

The difference in gross income, which came out as an increase of $646 per acre, is due to bigger fruit size and more fruit being classified as desirable (marketable).

For growers, that kind of data can make it easier to rethink assumptions about how much fertilizer is needed and whether different product formulations or application strategies can improve fertility program efficiency.

“In many cases, you end up applying less fertilizer, and that can be uncomfortable at first,” Rogers said. “But when you track it through tissue sampling and see that your levels are staying where they need to be, that’s when it starts to make sense.”

Efficiency under pressure

Efficiency has become a bigger focus across the industry, especially as growers navigate rising costs and tighter regulations.

Nitrogen management is one example. Nutrients can be lost through leaching after rainfall or irrigation and through volatilization in certain soil conditions.

Rogers said AgroLiquid’s approach is focused on improving how nutrients behave in the soil, with product formulations designed to help keep nutrients available in the root zone longer and better aligned with crop demand.

Improving nutrient use efficiency is also becoming more critical as regulatory pressure increases around nitrogen use.

The goal is to make every application count.

Adjusting throughout the season

Advances in fertigation have also changed how growers approach timing. Instead of applying large amounts of fertilizer upfront, more operations are shifting toward smaller, more frequent applications.

“With the ability to apply less fertilizer more often, we can be much more efficient,” Rogers said.

That approach gives growers the flexibility to adjust both rates and product choices based on current conditions rather than sticking to a fixed plan.

For permanent specialty crops, that flexibility matters.

“We’re always fertilizing next year’s crop,” Rogers said. “What you do this season is going to impact what you see next year.”

Balancing tradition and change

Shifting away from established practices is not always easy. Many growers have relied on the same fertility programs for years.

But that conversation is starting to change as more data becomes available, including product field trials from companies such as AgroLiquid.

Those results suggest that more targeted nutrient programs, supported by specific product technologies and data-driven adjustments, can maintain and in some cases improve yields while reducing overall inputs.

For growers, the takeaway is not necessarily to do more. It is to be more intentional.

“It’s about understanding your soil, understanding your data and making decisions based on that,” Rogers said.

FAQs

Why is soil sampling important?

Soil sampling helps growers understand nutrient levels and guide fertilizer decisions.

What is tissue sampling used for?

Tissue sampling confirms whether nutrients are reaching the plant during the growing season.

How can sodium affect potassium uptake?

Elevated sodium levels can interfere with potassium uptake by the crop.

What did AgroLiquid’s trial data show?

The trials showed reduced fertilizer use while maintaining yields and increasing gross income.

Why are growers changing fertilizer strategies?

Rising costs and tighter regulations are encouraging more efficient nutrient management.