This article is part of the Farm Journal multimedia series, which is designed to help improve bottom lines by maximizing yields, minimizing inputs and improving stewardship. Use this as your business guide to understand and implement zone management and the tools that make it possible.
The drive to enhance yields and nutrient stewardship through variable-rate technology (VRT) might have you chomping at the bit. Before you can run, though, you must walk—and have the hardware and equipment necessary for the journey. Here are six considerations to set up your farm for success with VRT.
Your timeline. "We start with a farmer’s goals and a time frame for achieving those goals," says Brad Beutke, who works with Farm Journal Field Agronomist Ken Ferrie at Crop-Tech Consulting to help farmer-clients develop a game plan for VRT.
The process of creating a timeline forces farmers to walk through how VRT could change their production practices, machinery and technology use.
"Farmers typically adopt VRT populations and sidedress nitrogen around the same time," says Isaac Ferrie, an associate at Crop-Tech Consulting. "For example, it’s helpful to know if
a farmer wants to step into VRT population in the next year and then add VRT nitrogen within three years. Sometime in that time frame, that farmer would also like to improve to RTK accuracy."
The longer it takes you to implement VRT, the higher the likelihood of compatibility issues with equipment, Ferrie cautions.
Take inventory. The next step is to list all of the equipment a farmer has on hand: GPS receivers, guidance equipment, monitors, rate controllers, etc. This step benchmarks where a farmer is today with where he or she wants to go. This step seems straightforward, but it often yields surprises.
For example, Beutke worked with a farmer who was considering VRT nitrogen and had tallied a ballpark figure to set up his current sidedress toolbar. When they evaluated all of the components he already had, the total was one-tenth of his original estimate.
As VRT becomes more widely adopted among farmers, manufacturers offer more factory-ready options. This might change a farmer’s course.
"Figure out the dollar-for-dollar amount to retrofit a current planter or buy a used or new planter set up the way you want," Ferrie says.
Farmers can work with fertilizer dealers to outfit rented sidedress toolbars for VRT with a quick-attach setup for a ground-driven piston pump.
Dennis Noland, who farms near Blue Mound, Ill., says a planter trade-in served as the catalyst for his farm to start VRT populations.
"We’ve been doing variable-rate population since 2008. Before, our planter had a ground drive; when it came time to trade it in, we decided to upgrade to a hydraulic drive because we knew that VRT population was next for us," he says.
The following year, Noland started using variable-rate nitrogen. To get set up for VRT sidedress, the farm used an existing toolbar replumbed and outfitted to vary rates on the go.
"Along the way, we’ve tried to make decisions that kept our equipment compatibility simple. For us, it made sense to use one monitor for the combine, planter tractor and sidedress tractor so we didn’t have to buy extra equipment," Noland says. "We did eventually add a second monitor for sidedressing because the time frame overlapped with planting soybeans."
Whether it’s equipment you own or rent, there are many paths farmers can take to be successful with VRT.
Mark Baer of Sun Ag Supply in Tremont, Ill., has worked to upgrade his toolbars along with his customer who are adopting VRT sidedress.
"Six years ago, we started switching out our existing toolbars for new ones that were VRT ready. Now we order all our toolbars set up for VRT with a rate controller, hydraulic pump and variable-flow nozzles," Baer explains.
The fertilizer dealer charges $3.50 per acre to rent a toolbar (straight rate or VRT), and it’s roughly $2,000 more to order a VRT-ready toolbar.
Identify who will do what. As you map out your path to VRT, it’s important to include crop consultants, seed dealers and/or ag retailers, particularly when evaluating software.
"If you are paying someone to develop and process maps, ask about the cost for the file types you’ll be using," Beutke says. "We have different cost structures for different file types, depending on the time and software it takes to create the file."
Follow up by asking about their experience level and how they can support those files in the field.
Consult your precision ag dealer. Understand the support system of your OEM or aftermarket dealer.
"Check the knowledge and experience of your dealer with what you’re trying to achieve," Beutke says. "We’ve had farmers experience a disconnect when their dealer understands variable rate but not the idea of management zones."
If you mix equipment brands, know who will support which components when a problem arises in the field.
Consider the source. "Right now, there’s a bigger market than ever for used equipment for VRT," Beutke says. "Equipment that is 10 years old can still do what we need it to do in the field for one-third to half the cost."
But he cautions that older equipment does come with the risk that it could be harder to get support in the field or help with installation.
The right way. Regardless of how you map out your path to VRT, respect proper set up and calibration procedures when adjusting equipment.
"You have to change how you plumb the toolbar so that the connection between pressure and flow is broken," Beutke explains. "A true variable-rate liquid system requires variable orifice nozzles feeding knives or drag tines. Coulter inject systems aren’t the best choice because of fluctuating flows and pressures."
When farmers switch to VRT, applying inputs where they are needed is top of mind. Regular calibration is key to a successful VRT process.
"Equipment has to be dialed in and guidance properly set up to synch the tractor, planter and toolbar," Beutke says. "Make sure you evaluate your tractor to confirm it has the capacity
to run all of these systems—hydraulic, air and electric."
All of the baby steps before running to the field with VRT will eventually pay off.
"It was eye-opening when we reviewed our yield data," Noland says. "Even when we think we had a uniform field, there are still zones to manage. We also know we’re putting inputs where they matter. For example, we used to push population on low-producing ground. With VRT, we lowered the population, which actually increased yields."
To learn more about equipment compatibility and see diagrams of VRT-ready implements, visit
You can e-mail Margy Eckelkamp at firstname.lastname@example.org.