One thing long-time no-tiller Roy Pfaltzgraff likes to do at his research farm and education center is challenge other farmers to question their practices when it’s necessary

Row spacing is a prime example: Oftentimes major manufacturers “tell us what we’re going to do,” he says, but growers are responsible for determining what works best on their own farm. While variables like location and soil condition play a part in determining row spacing, a shift toward narrower rows has occurred in recent years — from 36-inch rows down to 15-inch rows in some cases. 

To better understand the reasoning behind the narrow spacing and its possible effects, the fourth-generation Colorado grower closely examined the key elements of this strategy. 

A Question of Numbers

One of the first crops Pfaltzgraff recalls experimenting with on row spacings was drilling sunflowers, a crop his family has been raising since the 1970s. 

“If you don’t know anything about sunflowers, they have tremendous root systems. There’s research that shows sunflowers can go down 20 feet and they’ll cycle micronutrients up into the root zone,” Pfaltzgraff says. “We’ve always found our best crops follow sunflowers as long as we control evaporation.”

In early row-spacing experiments, Pfaltzgraff drilled the same population of sunflowers that he would have planted, about 14,000 plants. Although the seeds germinated, the resultant stand was fragmented and Pfaltzgraff recalls being able to walk across the field without touching a plant.