Spinner spreaders aren’t just for your local fertilizer dealer anymore. Those high-capacity box rigs that you’d hire someone to pull are now being purchased by farmers who have enough acres to justify the price tag. Farmers buying say it gives them more control over when their dry, granular fertilizer is applied.

“Definitely the market is shifting to growers because they are getting bigger,” says Ingrid Livingston, marketing director for New Leader, the nation’s largest spreader manufacturer. “If they have enough acres, 3,000 to 5,000, they know that long-term if they buy this and apply dry fertilizer themselves, it will pay for itself.”

John Fulton, extension specialist with Auburn University, estimates sales of these dry boxes in his home state of Alabama have increased anywhere from 20 to 50 percent among farmers in the last two years.

Farmers are typically buying the trailer-drawn units that can be pulled behind a tractor or mounting units on truck frames they already own. Self-propelled sprayers equipped with dry-box capabilities provide another option. Some farmers have worked their way up to commercial truck-propelled rigs called “floaters” on the used market.

The uptick in sales coincides with changes in nutrient management practices. In the last two years, there has been a push in topdressing corn. Spinners mounted on a high-clearance frame give farmers another way, in addition to side-dress units, to do that.

“I think this [topdressing trend] started because farmers are looking for ways to supply N after wet springs when some of the pre-plant N gets lost,” says Dr. Fabian Fernandez, crop sciences professor with the University of Minnesota.

Another driver is the increased use of micronutrients, including zinc, boron, and manganese associated with grid soil sampling.  The prescription created from the sampling often calls for rate changes of each nutrient independently of the other nutrients. Spreaders can be equipped with dividers that allow for multi-product application in a single trip.

“This capability really developed a couple decades ago with the evolution of air machines in the application market,” says Pauley Bradley, John Deere nutrient application product manager. “It’s only been in the last ten years that the same capabilities to compartmentalize dry fertilizer sources that independently vary their rate on the go were built into dry spinner spreaders.”

Farmers who are looking to buy a new spinner spreader will find the units have changed a lot in the last 10 years. In the old days, they got a bad rap for having an uneven application and limited spread width that would take days to cover fields. New designs and technologies, coupled with improved fertilizer formulations, have addressed those issues (see sidebar on what to look for).

“Ten years ago, the maximum spread width was 50 to 60 ft., so it would take time to put out granular fertilizer,” says Auburn University’s Fulton. “But today, you can get a spreader applying fertilizer 90 to 100 feet, and cover a lot of acres per hour.”

Adds John Deere’s Bradley: “Some fertilizer manufactures have optimized their formulation to make their prills harder and a little larger so the spinners throw them further.  This translates to wider spread widths (90 or 100 ft. rather than 70 or 80 ft.) which means fewer passes in the field and more acres per hour/day.” 

Next, you'll find some of the technologies and features to consider when shopping for a spinner spreader