People tend to walk at different speeds. When you are pushing a spreader, this difference in walking speed can cause problems.
Some textbooks will tell you it doesn’t matter how fast or slow you push a lawn spreader; the results will be the same. LSU AgCenter research has proved that this is not true. A change in operating speed will affect the delivery rate from both drop and rotary spreaders, and, to a lesser extent, the pattern from rotary spreaders.
Drop Spreaders
As the operating speed of a drop-type spreader is increased, the application rate will decrease. At lower speeds, the rate can be twice the recommended rate; and at higher speeds, the rate can be 40 percent to 50 percent of the recommended rate. Only a 10 percent change in speed can cause a 5 percent to 7 percent change in rate.
Rotary Spreaders
Speed affects pattern less than rate. Pattern changes were not significant unless speed was decreased at least 25 percent or increased 50 percent. Rate, however, changed significantly with a speed increase of only 8 percent.
What is Correct?
Homeowner spreaders are generally calibrated to deliver the correct rate and pattern at a walking speed of 2.75 mph. Professional spreaders, which are more likely to be pushed by physically fit young males, are typically calibrated at 3.0 mph. If you push your home lawn spreader at 2.75 mph (a relatively slow walking speed), you should get the correct rate and pattern.
Remember, speed will affect the performance of your spreader. Try to push your spreader at the recommended speed of 2.75 mph.
The LSU AgCenter and the LSU College of Agriculture