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2022 Shaping up to be Challenging Year for Ag

With reported shortages of ag inputs, disruptions in supply chains, and high input prices, 2022 is shaping up to be a challenging year for agriculture.

Recently, Purdue Extension experts Jim Camberato and Alex Helms shared some thoughts on the fertilizer situation. Camberato is a soil fertility and plant nutrition specialist at Purdue University. Helms is a Purdue farm technical coordinator.

“Fertilizer rate decisions have more potential impact on profits when soil test levels of a nutrient are deficient, because yield can be decreased by nutrient deficiency to an extent that offsets the savings of reduced fertilizer rates,” they said. “This approach to fertilization is often called the ‘Sufficiency Approach’, where the rate applied is targeted to produce the highest return to fertilization in that season without regard to the impact on future seasons.” They said that this has not been the philosophy recommended by Purdue for at least the last 40 years.

What they have recommended is the “Build-up and Maintenance” approach (or “Build-up, Maintenance, and Draw-down” approach in the original Tri-State recommendations). “This approach was used because it minimized the potential for yield loss due to nutrient deficiency and gave farmers the flexibility to skip a fertilization when fertilizer prices were high, commodity prices were low, fertilizer was unavailable, field conditions were unsuitable for application, etc.,” they said. “This conservative approach to fertilization was well-suited to farmers who owned the land they farmed or had stable leases on the land they rented because the additional P and K they had added over several years remained in the soil and could be taken advantage of in later years if maintenance rates of fertilizer could not be applied.” Unfortunately, they stated that this is not the most profitable approach in times of high fertilizer prices (if expected to fall in future years) or when farmers are cash renting on a yearly basis.

“We began to conduct experiments to gather the data necessary to make ‘Sufficiency’ recommendations for K in 2019 at the Southeast Purdue Ag Center and in 2020 at the Northeast and Davis Purdue Ag Centers,” they said. Research continues, and they do not have enough data to make recommendations at this point. “The early results support what most researchers suspect – the amount of fertilizer needed at deficient soil test levels to maximize dollar return to fertilizer is less than the ‘Build-up recommendation’,” they said. “We illustrated this with the soybean data from 2020 – the SEPAC data from 2019 told the same story.”

Camberato also shared online resources that may help with decision-making: a spreadsheet tool and additional background information.

If you want Purdue’s most current recommendations for N, P, and K and a means for comparing fertilizer costs try this spreadsheet tool:

Additional background information, including more detailed papers on “Thoughts on Profitable Fertilizer Rates,” “Using Phosphorus and Potassium Fertilizers Wisely,” and “Nitrogen Management Guidelines for Corn in Indiana,” are available within the original stories: “Thoughts On Profitable Fertilizer Rates,” and “New Calculator Tool For N, P, And K Recommendations And Fertilizer Cost Comparisons,” at Purdue Pest & Crop newsletter,

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