Sports turf topdressing is the act of applying a conditioner such as Profile™ Field and Fairway™ or Turface® MVP® or a mix of soil products directly onto the top of the playing surface. Topdressing smoothes out the surface of the athletic field, but more importantly it fills the aerification holes with amendments to keep these channels open for air and water to move into the root zone. Topdressing with calcined clay also keeps surfaces drier during rain events. There are several schools of thought on which topdressings to use.
- Sand is a common topdressing material, but only provides porosity where the sand particles bridge to create pockets of air.
- Calcined clay provides internal pore space as well as bridge pore space between particles. Calcined clay also holds moisture and nutrients benefiting the turf. At a minimum, topdress with sand, but many professionals are experiencing the added value when they topdress with a calcined clay like Profile™ Field and Fairway™ or Turface® MVP®.
- The benefits of topdressing with a calcined clay are that it leaves channels in the filled aerification holes, permitting an excellent exchange of water and air at the root level. This promotes a deep, strong root structure, which is necessary to handle the day-to-day abuse of athletic turf. Due to the long degradation time for Turface®, it also prevents future compaction.
Topdress turf areas with conditioner at a rate of 500 pounds per 1000 square feet. This should be accomplished by the use of a hopper-type topdresser, a properly calibrated rotary spreader, or the bucket of a tractor. One year later, repeat the application of 500 pounds of calcined clay.