It’s mid-February, and while the fields are still cold, your sprayer clock is already ticking. Spring burndown, pre-plant herbicide applications, and early-season passes are closer than they feel — and a sprayer that hasn’t been properly calibrated or inspected is one of the most expensive gambles you can take heading into a planting season. A miscalibrated boom can over-apply by 10–15%, burning through high-cost chemistry, damaging crops, or leaving you short of full weed control. This checklist is built specifically for corn and soybean producers across the Parallel Ag territory — from the Oklahoma and Texas panhandle up through Kansas, Missouri, Illinois, Iowa, and Minnesota — so you can go into spring applications knowing your machine is dialed in.[agcrops.osu]
And if your sprayer needs service, Parallel Ag’s RoGator/TerraGator Winter Inspection Special is running through February 28, 2026 — don’t miss it.[parallelag]
Why Calibration Cannot Wait Until the First Field Day
Once burndown season arrives in March and April, the window is short. Weather, field conditions, and workload stack up fast, and pulling a sprayer out of the shed on application day without a calibration check means you’re rolling the dice on every acre.[lgpress.clemson]
According to extension guidelines from Iowa State and Ohio State, every sprayer should be fully calibrated before the first use of the season and recalibrated any time nozzles, travel speed, or operating pressure changes. The USEPA and USDA both recommend that actual application rates stay within 5% of intended rates — anything outside that range means you’re either wasting money or leaving pest control on the table.crops.extension.iastate+1
The good news: a thorough pre-season sprayer inspection and calibration takes 30–45 minutes when done methodically. Here’s exactly how to do it.[popprobe]
Step-by-Step Pre-Season Sprayer Calibration Checklist
Work through these checks in order — mechanical integrity first, calibration second. Skipping straight to calibration on a machine with worn nozzles or a leaking pump gives you meaningless numbers.[lgpress.clemson]
Phase 1: Mechanical Inspection
- Flush the tank and plumbing. If antifreeze was used for winterization, flush completely with clean water before introducing any chemical.[cropscience.bayer]
- Inspect the pump. Check for seal wear, belt tension, and proper pressure output. A pump that can’t hold steady pressure will produce inconsistent results across the boom.
- Check all hoses, fittings, and clamps for cracks, chemical residue buildup (a sign of previous leaks), or dry rot from winter storage.[blog-nwcrops.extension.umn]
- Grease all fittings. Boom pivots, lift arms, and agitator components should all be greased before the season begins.[cropscience.bayer]
- Check the main tank strainer and inline filters. Clean or replace any screens with visible debris or buildup.[crops.extension.iastate]
- Inspect boom sections and section control valves for damage from the previous season — bent booms or sticky valves cause uneven coverage that calibration alone won’t fix.[farmprogress]
- Test all boom section controls, including electric or hydraulic shutoffs, to confirm they open and close fully and on command.
Phase 2: Nozzle Inspection and Replacement
Nozzles are the single most important variable in spray accuracy — and they’re cheap insurance compared to the cost of misapplication.[lgpress.clemson]
- Remove all nozzles and inspect for wear, cracking, or plugging.
- Clean nozzle strainers and screens of any debris.[cropscience.bayer]
- Run the sprayer with clean water and visually check the spray pattern from each nozzle. Irregular, streaky, or asymmetric patterns indicate wear or damage.[crops.extension.iastate]
- Measure output from each nozzle using a catch jar or a Spot-On Sprayer Calibrator. Any nozzle spraying more than 10% above or below the average output of all nozzles should be replaced.striptillfarmer+1
- Check fencerow nozzles separately — these take more abuse than any others and are frequently the first to fail or plug.[corteva]
- Verify nozzle alignment. Boom impacts during the prior season can shift nozzle holders, disrupting spray pattern overlap. Adjust any holders that are bent or off-angle.[crops.extension.iastate]
- Confirm nozzle type is appropriate for your planned products. Dicamba and 2,4-D applications require approved low-drift nozzles — check current product labels before proceeding.[crops.extension.iastate]
Phase 3: Calibration for Application Rate
Once you’ve confirmed mechanical integrity and nozzle uniformity, you’re ready to calibrate for actual application rate.[agcrops.osu]
- Fill the tank at least half full with clean water.
- Measure the distance between nozzles (in inches).
- Drive a measured course in the field at your normal spraying speed and record travel time in seconds. Run the course twice and average the results.[agcrops.osu]
- Park the sprayer and run at the same pressure. Catch output from each nozzle for the same number of seconds as your travel time.[agcrops.osu]
- Calculate your actual gallons per acre and compare to your target application rate.
- If your actual rate is more than 5% off your target, adjust travel speed or operating pressure — not both at once. Reducing speed increases rate; increasing pressure also increases rate but also increases fine, drift-prone droplets.[agcrops.osu]
- Recheck after any adjustment and repeat until you’re within 5% of your intended rate.
Explore Parallel Ag’s sprayer inventory and precision application equipment here: https://www.parallelag.com/new-equipment-showrooms/
Don’t Overlook Precision Technology on the Sprayer
Modern boom sprayers are loaded with technology that also needs a pre-season check — and it’s easy to skip this step when you’re focused on mechanical items.[farmprogress]
- GPS and auto-steer: Verify signal accuracy, update firmware if available, and confirm that boom section control maps are loaded correctly.
- Rate controllers: Run a bench test to confirm the controller is communicating accurately with the flow meter.
- Section control: Test each boom section individually to confirm that automatic shutoffs are triggering at field boundaries and previously sprayed areas.
- Flow meters: Check for debris or calibration drift — a flow meter that’s off by even 3–4% compounds into significant misapplication across thousands of acres.
For precision ag support and upgrades, the Parallel Ag team can help: https://www.parallelag.com/precision-ag/
Customer Scenario: A Central Kansas Corn and Soybean Farmer Gets Ahead of the Season
Marcus farms 3,200 acres of corn and soybeans in central Kansas, running a self-propelled sprayer for burndown, pre-emergence, and post-emergence passes. Last year, he caught a late-season calibration issue that had been costing him roughly 8% over-application on post-emerge passes — extra product cost he couldn’t recover. This February, he scheduled a full pre-season inspection through his local Parallel Ag service team, had nozzle wear addressed before the season, and ran a complete calibration with clean water before the first burndown pass. He estimates the calibration work alone paid back in product savings within the first two applications.
If you’re a producer near Chickasha, Oklahoma, or across the Kansas plains and want to get your sprayer prepped and inspected before the busy spring window, the Parallel Ag team is ready to help — schedule your service appointment here: https://www.parallelag.com/contact-us/
Take Advantage of the February 28 Sprayer Inspection Special
Right now, Parallel Ag is offering a $578 RoGator/TerraGator Sprayer Inspection Special that includes:[parallelag]
- Full boom system check and necessary adjustments
- Suspension cylinder and accumulator check
- Boom accumulator pressure check
- Hydraulic pressure checks
- 10% off parts and labor on all inspection-related repairs
- Service call included
This special expires February 28, 2026, and is available at Parallel Ag locations including Carthage, Chickasha, Dalhart, Durand, Fairview, Fulton, Liberal, Lubbock, Marshall, Montgomery City, and Mt. Pleasant, among others.[parallelag]
Don’t wait until the first warm application day to find out your sprayer isn’t ready. Schedule your inspection now: https://www.parallelag.com/service-department/
View current parts and service offerings here: https://www.parallelag.com/parts-department/
Conclusion
A sprayer that isn’t calibrated is a liability — not just to your input budget, but to your weed control plan and your crop. Taking 45 minutes in the shop now, before the first warm day forces your hand, is one of the best ROI decisions you’ll make all season. Whether you run a self-propelled machine, a pull-type, or a mounted boom, the fundamentals are the same: inspect first, calibrate second, and verify with every major change.[popprobe]
The Parallel Ag service team is standing by to help you get your sprayer — and every other piece of equipment — dialed in before spring. Equipment availability, service scheduling, and inspection specials vary by location, so check parallelag.com or call your nearest store to confirm what’s available near you.[parallelag]
Frequently Asked Questions
Q: How often should I calibrate my boom sprayer?
A: Calibrate before the first application of every season, and recalibrate any time you change nozzles, adjust operating pressure, or change your target travel speed. Extension specialists recommend checking calibration accuracy at least every 3–4 applications during the season as well.[content.ces.ncsu]
Q: How do I know if my nozzles need to be replaced?
A: If any nozzle’s output varies more than 10% above or below the average output of your other nozzles during a flow test, it should be replaced. Visual signs include irregular spray patterns, streaking, or reduced pattern coverage width.cropscience.bayer+1
Q: What’s the consequence of running a slightly miscalibrated sprayer?
A: Even a 10% over-application error on a 3,000-acre operation at $15/acre in herbicide input can mean $4,500 or more in wasted product per pass — before considering potential crop injury or regulatory exposure. Under-application risks inadequate weed control, resistance pressure, and yield drag.[agcrops.osu]
Q: Do dicamba and 2,4-D applications require special nozzle setups?
A: Yes. Both products carry strict nozzle and application requirements on their labels to minimize drift. You must use approved low-drift nozzle types and meet specific droplet size requirements. Always check the current product label — not last year’s — before your first application.[crops.extension.iastate]
Q: Can Parallel Ag help me select the right nozzles for my spray program?
A: Absolutely. The Parallel Ag parts and service team can help you evaluate your current nozzle setup and match the right tips to your planned products and application speeds. Reach out at https://www.parallelag.com/contact-us/ or stop by your nearest location.
Suggested Parallel Ag Links
- Sprayer Service & Inspection Specials – https://www.parallelag.com/exclusive-offers/
- New Sprayer Equipment Showrooms – https://www.parallelag.com/new-equipment-showrooms/
- Precision Ag Technology – https://www.parallelag.com/precision-ag/
- Parts Department – https://www.parallelag.com/parts-department/
- Schedule Service or Find a Location – https://www.parallelag.com/contact-us/
