April 3, 2002 | By: Laura Skillman

Using fertilizer in or near rows at planting can be a benefit in specific cases but is not right for all occasions.

University of Kentucky Cooperative Extension Service agronomist Lloyd Murdock said he has received numerous questions regarding the use of row fertilizer now that planting is at hand.

Farmers are so interested in row fertilizer because it makes the crop look good and gives them a little bit of a yield advantage in no till, he said. In conventional and reduced tillage, it still gets the kick start but doesn't carry through to the end with improved yields.

"Basically, row fertilizer data from Kentucky and surrounding states all indicate that there is no advantage to it in anything except no-till," he said. "The data shows the no-till advantage comes when you plant early, generally the last of March of early April. When you move to the middle of April and beyond that advantage is lost. That is because the soil has warmed so that you get a rapid growth."

Row fertilizer is placed either in the furrow or within 2 inches of the row at planting. Research shows the response can be up to 6 bushels per acre. If a person is trying to figure expenses versus income from additional yield, that is the figure Murdock recommends using in determining those calculations.

But, he notes that it also can reduce yields. For instance, that initial kick row fertilizer provides results in more vegetative growth so the plant is larger. If there is a drought in the middle of the season, that plant has used most of its water for the vegetation and doesn't have much reserve for the grain.

The best way to apply corn fertilizer is a split application using a preplant application followed by a second application four to six weeks after planting, he said. He recommends using row fertilizer only in early planted no-till fields.

For those considering row fertilizer, it is important to note that 75 percent of the early response comes from nitrogen and the remaining from phosphorus, Murdock said.

"If it is placed in the furrow, 10 pounds of nitrogen is needed to get the quick start but as much as 15 pounds can be used without being detrimental to the stand," he said. "If it is being placed 2 inches from the furrow, 20 pounds of nitrogen and phosphorus is needed and as much as 40 to 50 pounds can be used without causing a detrimental effect on the plant."


Lloyd Murdock, (270) 365-7541