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Fertilizer supplements: Some questions to ask

Asked how best to approach glowing claims about supplemental fertilizers in place of fundamental fertilization, Rick Cartwright first points to humanity's vulnerability to a good sales pitch.

Farmers are like everyone else, says the Arkansas Extension plant pathologist. “We've all been suckered by a good sales pitch. But I encourage farmers not to get suckered into something that can hurt a crop in a given year and also damage the farm long-term.

“I hate to say it, but more skepticism is needed about any product or recommendation. And that includes university recommendations — please, check them out. Just because people look you in the eye and claim something doesn't mean it's true.”

The current situation with fertilizer supplements has been developing over a few years, “and it's time to draw attention to it. Reason needs to be injected into these claims.

“Some products are legitimate supplements or micronutrients. If they're marketed that way and there's data to support them, no problem. But if they're being sold to replace major nutrients in large amounts, you're looking at a scam.”

When considering a fertilizer supplement, Cartwright suggests farmers ask the following:

  • What's the actual fertilizer content of the product? “Those figures must be legally supplied to the farmer.”
  • Once those figures are provided, calculate the actual units. What is the recommended application on a per acre basis? “Multiply those together and you'll see what the salesmen are actually recommending compared to what independent sources say the crop needs based on the soil tests. If they aren't equivalent, it's a scam.”
  • What source and form of the element or nutrient in the product? “Some nutrients are readily available to plants in one form but not another.”
  • Question efficiency claims. “If they claim, due to efficiency or some other reason, 5 pounds of actual nitrogen in their product is equivalent to 46 pounds of actual nitrogen in 100 pounds of urea, consider that closely. If true, that means the urea is only about 10 percent efficient. Any university study will show that 100 pounds of urea applied properly is much more efficient than 10 percent. It'll be 60 percent-plus. Efficiency claims should be an automatic red flag.”
  • Who did the research cited and where did it come from? “The salesmen should be able to provide data and tell you if the company did research alone or if there were independent researchers that did replicated research in multiple locations. If that research information is available, great. Take that and call the researchers and ask for their feelings on the product. Call the researcher in Illinois or wherever and find out what he has to say. Surprise, surprise: sometimes companies fudge facts. If all they have are testimonials, be very skeptical.”
  • Is the salesman trying to dazzle you with words? “If they can't explain exactly what their product can do in easy-to-understand terms, be suspicious. If they can't talk my language, my first inclination is to wonder what they're hiding.”
  • Are they claiming their product is much cheaper per acre? “That's a giveaway. When I hear that, an alarm bell goes off. You know, ‘Instead of you paying $60 per acre for a full fertilizer program, I can give you this for $10 per acre.’ No way, no way.”
  • And finally, does it sound too good to be true? “If so, it probably is.”
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