Everyone wants an even fertilizer application. But come spring time, I see it time and time again where a homeowner tries to fertilize his or her lawn, and ends up striping the lawn with the fertilizer. Applying fertilizer unevenly will result in unsightly light green strips in a sea of dark green grass. What happens to cause the uneven fertilizer application with a rotary spreader could be a spreader malfunction, spreader miscalibration, or a careless application.
- Spreader Malfunction: This could be a result of the spinner not rotating at a proper speed, or the feeder gate not opening completely, or the feeder gate being partially plugged. Any of these will cause the fertilizer to be applied unevenly. It could be an over-application or an under-application. Making sure that the spreader is working properly and the fertilizer is free of clumps that could clog the spreader will help to make an even fertilizer application. Replace any worn out or malfunctioning parts to make sure that you can apply fertilizer evenly. And make sure that your fertilizer is clump free to keep it from clogging.
- Spreader Miscalibration: If the spreader is spreading too heavy to one side of the spreader, the lawn will not receive an even application. Adjusting the direction of the spread so that it is even is needed to correct this problem.
- Careless Application: This is the most common cause for an uneven application. It is tempting to spread the fertilizer pellets to the edge of where you saw them fall. However, this is not good. When a rotary spreader spreads fertilizer, approximately half of the material lands directly in front of the spreader, with the a quarter of the material to the left side, and a quarter of the material to the right side. The best way to spread is to spread the fertilizer back to the tire tracks from your last pass, thus making the sides receive an even amount of fertilizer.
- Drop Spreaders: Drop spreaders are their own animal. They apply a very accurate amount of fertilizer, but any slight deviation from the last pass can cause an uneven fertilizer application. The best way to avoid this is to replace the spreader with a broadcast spreader.
An even fertilizer application will help to make your lawn healthier, and it avoids those unsightly streaks in your lawn. Making sure that you have properly working equipment, free-flowing material, and accurate spreading will all help.