N-P-K nightmares: Fertilizer prices force farms to cut back


SALEM, Ohio — The price of anhydrous ammonia is up 55 percent. Straight urea, up 67 percent. Potash isn’t cheap either, up 55 percent. And those are just the increases recorded in the last six months.

There have been astronomical increases across the board in fertilizer prices in the past months, and reason enough for farmers to look at every available option to cut input costs.

Ohio State and other land grant university Extension specialists offer the following tips to save the most in your 2009 fertilizer budget:

Know your soils

Ohio State University Extension ag economist Barry Ward said high prices should get folks to study their soils long and hard and especially to understand nutrient needs on each field and on each farm. There’s no cookie-cutter formula for determining how much fertilizer you need, and high costs make it unwise to guess or over-apply.

Get your soil tested, and get everything you can out of the report. If you’re not sure how to read the report, get help from an agronomist or your county Extension agricultural educator.

Get specific

Ward also suggests producers take a serious look at grid sampling, which will allow even more precise application of nutrients — only where they’re needed, and at specific rates for maximum fertility.

If your soil test indicates the need for any nutrient, Iowa State University Extension fertility specialists John Sawyer and Antonio Mallarino say to apply only where the chance of yield increase is large enough to at least pay for the fertilizer.

And, if soil tests show phosphorus and potash are in high to very high levels, then enough may be “banked” that can be used next season, they said.

Withholding fertilizer may be an option, but a soil test is the only way to know if that will work.

Go ahead

Apply the nutrient needs for both corn and soybeans prior to planting 2009 corn, unless rates for nutrients will drop prior to the planting of 2010 soybeans, the Iowa experts urge.

If you’ve got to pay through the roof for fertilizer, try to keep the cost of application as low as can be.

Other sources

The Iowa experts say there are not many opportunities to eliminate nitrogen when prices are high — and it’s downright silly to expect high yields without a good fertility program — so it pays to look for alternative sources.

They mention using manure to supplement your ground’s nitrogen needs.

“If nitrogen fertilizer is in short supply or purchases have to be limited, it is better to apply some nitrogen to all fields than to skip fields, other than corn after alfalfa, as the largest yield gains come from the first increments of applied nitrogen.”

Ohio’s Barry Ward said, depending on your location, it’s beneficial to look into using municipal sludge as a fertilizer.

Upping efficiency

To retain nitrogen in the soil where it will be available to the 2009 crop, Extension fertility specialist Fabian Fernandez at the University of Illinois recommends the use of a nitrification inhibitor if the soil temperature exceeds 50 degrees.

Using a nitrification inhibitor helps stop or slow down the conversion of ammonium to nitrate and reduces the chance for nitrogen to leach from the soil.

Fernandez said it’s important to make sure soil has proper moisture content while you’re applying fertilizer, and to apply at the proper depth to keep ammonia gas from escaping.

Wait for spring

Illinois’ Fernandez said there is no great benefit for fall application of nitrogen to increase microbial activity against cellulose-laden residue left in corn fields.

With high prices, Fernandez said it is critical to have every pound of fertilizer going to crop yield. Spring side dress applications are more effective than fall because of the potential loss over the winter.

Push your pencil

Ohio State’s Barry Ward and other economists there have put much effort into compiling farm enterprise budgets that allow farmers to “pencil it out” — using a computer spreadsheet — to see exactly where the bottom line is.

Free updated budgets for 2009 are posted at http://aede.osu.edu/Programs/FarmManagement/Budgets/.

The most recent updates to the corn budgets allow producers to input ammonia, UAN and urea costs. Ward said the budgets will be updated throughout the year to reflect changes in fertilizer or crop prices.

Best rates

Another free tool available is the nitrogen rate calculator at http://agcrops.osu.edu/fertility.

The calculator figures optimum nitrogen rate recommendations using only two inputs: the price of corn at harvest and the cost of nitrogen at application.

Robert Mullen, an OSU Extension fertility specialist, said the goal is to apply the minimum nitrogen needed for maximum yield results, thereby saving farmers money on fertilizer applications.

Mullen said farmers he’s surveyed have revealed the calculator has helped them reduce nitrogen rates on some 5 million acres in Ohio, Indiana and Michigan.

“If nitrogen rates were reduced on just half of those acres, that would mean 60 million pounds less nitrogen added, translating into a $24 million annual savings in nitrogen costs,” said Mullen.

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  1. The Conklin Co. has been promoteing a complete soil test for years. We know a farmers needs to know not only N,P,K but minor & secondry elements also. We have been very successfull help farmers cut cost and get the maximum out of their input dollars. It was good to see the Universities are now talking about only putting on what is needed.
    Proper placement of the nutrients will also help reduce cost.


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