March 29, 2006 | By: Terri McLean

The continuing high cost of natural gas means farmers can expect to pay more for nitrogen fertilizer again in 2006, said Greg Schwab, Extension specialist in soil management at the University of Kentucky College of Agriculture.

Nitrogen, a major factor in corn production, is the No. 1 fertilizer input farmers use to impact yield. About 90 percent of the cost of nitrogen is associated with the cost of natural gas, which is the key component in nitrogen manufacturing.

“Fertilizer is starting to add up to a significant part of production expenses, whereas in the past it was relatively minor,” Schwab said. “Kentucky farmers’ fertilizer bills are going to be higher this year or they are going to have to learn how to get by using less nitrogen.”

With rising land, seed, fungicide, insecticide, fuel and labor costs to also contend with, most farmers cringe at the thought of paying more for nitrogen fertilizer. But Schwab said using less might not always be an ideal option.

“Using less is only a good idea if they were using too much in the past or if they change practices so that the nitrogen is used more efficiently,” he explained.

The best thing farmers can do to cope with higher nitrogen costs is to make sure they are not exceeding the recommended application rate, Schwab added.

“This may seem simple, but many farmers apply more nitrogen than what is recommended,” he said. “They look at the extra application as insurance. However, research results show that this insurance seldom, if ever, is needed.”

Farmers can also improve fertilizer efficiency by side-dressing nitrogen fertilizer to corn. Side-dressing means to wait to apply nitrogen fertilizer when the corn is about 24 inches tall.

“When nitrogen was relatively cheap, most farmers put all of the nitrogen on at or before planting,” Schwab said. “As the price of nitrogen increases, the value of side-dress applications increases.”

However, Schwab noted that side-dressing effectiveness is greatly determined by soil drainage. The method of side-dressing also determines its effectiveness and depends on the type of tillage, nitrogen form and placement in or on the soil.

“Poorly drained fields will be the ones most responsive to side-dressed applications,” he said. “If a farmer does not have time to side-dress on all of his corn ground, then he should select the wettest ground for side-dressing.”

Farmers who do plan to apply nitrogen prior to planting should do so as close to planting as possible to increase effectiveness, Schwab said.

“Some farmers in southern Kentucky have already started to apply nitrogen to corn ground. However, this is not a recommended practice. If soils become water saturated after nitrogen application, much of the nitrogen can be lost,” he said.

To learn about other ways to increase nitrogen efficiency and, therefore, reduce costs, Schwab encourages farmers to contact their county Extension agent.


Greg Schwab, (859) 257-9780