Jace Bertsch, global product marketing manager for The Toro Co., offers golf course superintendents his advice to make sure they get the best topdressing results to keep their courses in top condition:
1. Use sand with the same particle-size distribution as your original construction material.
If the sand you put down is either finer or coarser than the original construction material, you run the risk of creating an abrupt transition zone between the original material and the new topdressing material. This abrupt change in particle size can impede good water movement and make it difficult to maintain the optimum moisture content in the soil.
2. Be Consistent.
Our agronomists recommend applying a light topdressing once a week or once every other week during the growing season, depending on your labor resources. If you can’t maintain a consistent schedule, alternating layers of sand and organic matter can start to build up, at which point it becomes difficult to get good water movement through the soil profile.
3. Don’t skip aerification.
Aerification is an important process and weekly or biweekly application is not a replacement for core aerification. In most situations, courses still need to do annual or biannual core aerification to help remove organic matter.
4. Limit organic matter accumulation.
A good rule of thumb is to try to maintain the soil on your putting greens at a maximum of 3 to 4 percent organic matter by weight. Once you get above that, you start to have some issues with drainage, water infiltration and reduced gas exchange.
5. Apply topdressing in the morning.
Topdressing is best done early in the day because sand absorbs heat from the sun and can be abrasive on the leaves of the grass plants. Courses typically apply the sand, let it dry for a short time, then use a brush or drag mat to work it into the canopy (be careful not to overdrag as this can also damage the turfgrass). Finally, irrigate briefly to settle the sand.
6. Avoid overapplication.
Excess sand can be hard on reel mowers and other turf equipment. You may even want to avoid using groomers or brushes for a few days following application to reduce the amount of sand your mowers pick up.