Improving fertilizer efficiency with the planter pass

By Dusty Sonnenberg, CCA, Ohio Field Leader: a project of the Ohio Soybean Council and soybean checkoff

An important part of crop production with environmental stewardship is efficient fertilizer application. The 4Rs are a consideration that can partly be addressed by adding fertilizer to the planter. Selecting the right source, the right rate, the right time, and the right place all come into play with the planter.

• The right source: making at fertilizer application at the time of planting can utilize various fertilizer sources, and can be managed by adding either a liquid or dry fertilizer system.

• The right rate: the fertilizer rate can be variably applied with new technologies that are available on planters.

• The right time: research has shown that the timing of fertilizer placement is important and placing fertilizer during the planting application is beneficially both agronomically and environmentally.

• The right place: proper fertilizer placement can be made with a planter, compared to making an application either prior to, or after planting, so that the fertilizer is in a location where the new developing root systems can reach it when it is needed.

“Applying fertilizer with the planter provides a very efficient way to meet the crop needs in an environmentally friendly way,” said John Fulton, professor and Extension specialist in the Department of Food, Agriculture and Biological Engineering. “This also allows the potential to apply less and have it used more efficiently. This is something that could become mandated in the future, so now is a good time to check it out and learn.

“In some states it is nitrogen, but here in Ohio, phosphorus gets the most environmental attention. Fertilizer placement is one of the best management practices (BMPs) (in H2Ohio). Having a fertilizer placement system on the planter provides the option for this practice. Getting nitrogen and phosphorus placed accurately is important. The key is how to get proper fertilizer placement relative to the seed placement.”

There are understandable concerns, though, expressed by farmers when it comes to adding a fertilizer application to the planting process. The cost of the fertilizer equipment, the additional weight that is added to the planter by the fertilizer equipment and fertilizer products, the logistics of tending the planter with the fertilizer, and the narrower planting window due to weather and soil conditions all are legitimate concerns. Those challenges, however, can be overcome.

The second session of Precision U, hosted virtually by The Ohio State University’s Digital Ag Team, focused on improving fertilizer efficiency with the planter pass. Fulton, along with Matt Bennett, RSM for Precision Planting were featured in the discussion.

“Modern farming today is the act of giving up yield potential. It comes down to the fact that there are things that we do because that is what our operations withstand, as opposed to what is the right thing to maximize yield, and at the end of the day, ROI,” Bennett said. “The commodity of time in the spring is critical to a farmers operation. Making things less complicated is what farmers want.”

Adding fertilizer to the planter does add a little bit of complexity to planting season, but it all needs to be considered.

“The big question farmers ask is ‘Why should we consider fertilizer on the planter?’  We need to figure out a way to move fertilizer application from the fall to a springtime application. That is environmentally better,” Bennet said. “There are many choices of what products and methods we can use to apply fertilizer with a planter. The 2X2 is an ideal placement of N fertilizer (2 inches over from the seed, and 2 inches below the seed), but it is not necessarily the best location for P. Phosphorus is needed early V2 and beyond. The P needs to be near the root because is will not just move with soil moisture to the root. The ideal placement and the rate I want to apply are unique. Ideally N and P are applied at slightly different placements.”

Technology is progressing to allow for more specific placement.

“Looking back at the last 5 to 10 years, and the advancement in technology for controllers and sensors to be put on a planter to apply starter fertilizer is interesting,” Fulton said. “We can now equip planters simpler, and also meter the products more accurately than in the past. We want the crop roots to intersect the N and P at the proper times to benefit the crop as it grows.”

With this in mind, split fertilizer applications are something to consider.

“Placing nutrients at planting and in the growing season help mitigate the environmental concerns,” Bennett said. “Applying a part of the fertilizer needs with the planter and then following with a split application in a sidedress pass makes sense economically and environmentally. There are better sensors and systems now that don’t need filtered as much, or have the same plugging issues.”

Split fertilizer applications were a part of a research project conducted at Farm Science Review with Nate Douridas looking at managing nitrogen. The research evaluated applications with starter applied 2X2 with the planter and then follow-up with side-dress application, versus a side-dress application only, versus a full fertilizer rate applied with the planter only. Reviewing the results, the split application was the highest yielding. The full application rate made at planting was slightly lower. A full rate at sidedress only was lowest of the three.

“There are defined benefits to split application of N according to a Precision Planting study in Pontiac, Mich. in 2020,” Bennett said.

Adding fertilizer equipment to a planter does not take the place of doing everything else right. “Having good soil conditions, proper seed placement, (uniform spacing, depth, and into moisture), not compacting the soil, getting good seedling emergence and a uniform stand are still first priority. That plant needs the best environment possible to start life. We can’t go back and do over once it is planted,” Bennett said.

Fulton agreed.

“If the seed depth, spacing, and placement into moisture is not correct, then I am not gaining much with the fertilizer technology. The seeds need consistency of depth and placement into moisture. Each year is different and farmers need to make adjustments to the planter based on what environmental conditions are so that it leads to more uniform emergence,” he said. “If you get a good root structure going, that helps minimize competition and is beneficial in higher seeding rates. If the plant gets off to the best possible start, it utilizes the fertilizer better.”

With more technology, it is increasingly important to take the time to make sure the planter is calibrated and set-up when starting in the spring.

“The idea that we plant at the same speed and same depth across all acres is false without technology to make adjustments as we go,” Bennett said.

There are different application methods and various products that can place the fertilizer appropriately near the seed without burning issues, and still vary the rate.

“There are sensors on the market that allow it to run a very low rate in thin band without plugging,” Bennett said. “A lot of guys experience with a liquid system was a ball floating in a tube that was 30 feet away. We are long past that now.”

The improved technology can allow for more efficient fertilizer use even within the confines narrower planting windows in the spring.

“Farmers need to use sensors to validate what is happening on the go,” Fulton said. “With the amount of money that we are putting out in seed and fertilizer, on a per second or per minute, or per hour basis, you want to have the confidence that you are doing it right and as planned to reach your planting goal. Accurate liquid control now is easy to achieve with the current technologies available. One of the real advancements that make this possible is pulse width modulation (PWM) technology that allows the technology to respond quicker and on a row-by-row basis.”

The next Precision U session will be held on January 19^th, and cover Pre-season Crop Protection Decisions, featuring Dr. Mark Loux and Dr. Scott Shearer from The Ohio State University.

For meeting details about upcoming Precision U events and to register, visit: https://osu.zoom.us/webinar/register/WN_tJDBYxADQQSa6aRr_106Rw.