Do you know the best practices for calibrating your spreaders?

Having a properly calibrated spreader means you won’t over or underapply the product. (Photo: SiteOne Landscape Supply)

As temps begin to rise, lawn care operators (LCOs) dust off their spreaders and ready them for the season. Compared to stand-on models, walk-behind spreaders can provide a higher level of maneuverability and also financial savings, says Jason Wilk, senior product manager for Echo.

“Walk-behind spreaders are more cost-effective, especially for commercial users that offer a lawn care treatment package but don’t offer the service as their primary business,” Wilk says. “Walk-behind spreaders can also be used in areas where some ride-on units may not be able to get to, such as a fenced-in yard with a standard gate opening.”

To ensure walk-behind spreaders provide consistent applications, LCOs must calibrate the equipment — and maintain them properly throughout the year.

Even application

Jason Wilk

Before the season begins, LCOs need to calibrate their walk-on spreaders. Calibrating a spreader involves measuring the product output over a specific area to ensure a proper, even application, Wilk says.

Chemical manufacturers often provide the recommended spreader settings on the product label, which serve as a good starting point, says Christian Jessel, equipment category manager at SiteOne Landscape Supply. 

With that as the baseline, each spreader then needs to be calibrated. One method is the spread, sweep and weigh calibration method, usually on a concrete surface, Jessel says. This allows the operator to identify distribution issues with the spreader that require mechanical adjustment to the spread-pattern control system.

Christian Jessel

“They have to ensure that the amount of material that they are allowing to pass through the spreader opening is the exact desired amount — in pounds per 1,000 square feet or pounds per acre — according to the suggested application rates on the bag label,” Jessel says.

When done incorrectly, users can misapply a product — causing either too much or too little of the product to reach the turf.

“Too much can lead to extensive turf damage, while too little will provide weak results leading to some unhappy customers,” Wilk says.

After finishing an application, there should be little to no material left. 

“If the material runs out too quickly or if you still have half or more material left over, the spreader will need to be readjusted and recalibrated,” Wilk says.

Over or underapplying materials can lead to callbacks, reapplications or damage to the area, Jessel says. Lawn striping can also occur when excess material is being spread heavily to one side or the other of the spread pattern.

“Once calibrated properly, a unit should not require additional testing until the start of the next spread season,” Jessel says.

Proper maintenance

To get the most from their equipment, LCOs also need to follow the manufacturer’s recommended maintenance schedule. That includes ensuring the tires have the correct air pressure, lubricating the grease fittings on the wheel axles or the gearcase once or twice a year and tightening the fasteners properly, Wilk says.

“When using harsh chemicals, it’s also recommended to rinse the unit with plain water, as some chemicals can cause rapid corrosion,” Wilk adds.

The most common cause of unexpected failures with a spreader’s hardware is not keeping it clean, Jessel says. Cleaning after each use helps avoid issues with sticking mechanisms or premature corrosion.

LCOs also must ensure the gearbox and transmission are in good working order, grease points are checked and lubed, the hopper isn’t damaged/missing parts and handles/handle grips are working properly.

“If installed, also check the side-deflector/baffle/side-shield operation,” Jessel says. “When these are needed, they must work.”