In this blog post, we’ll discuss cultural practices that foster healthy warm-season turf. As we begin to warm up and move into the summer, it is important to plan how many—and which—practices should be employed in order to maximize the growth of warm-season turf. The best time to perform any of the below practices is when the turf is actively growing. Typically, that will be when the daytime high temperature added to the nighttime low temperature equals 150 (for example, an 80°F daytime high plus a 70°F nighttime low equals 150). This will help shorten recovery time, as each cultural practice can have varying degrees of initial damage. It’s important to note that this damage is necessary in order to have a healthy stand of turf. Timing around events is critical and can be a factor in how many cultural practices can be performed. Let’s get into the different types of cultural practices:

Aeration

This involves breaking up or opening up the soil surface to relieve compaction and remove thatch. Compacted soils can greatly inhibit the amount of pore space between soil particles. With increased pore space, you get increased nutrient availability, deeper plant roots, and improved drainage. Often, topdressing with sand follows aeration, which changes soil structure and porosity.

Detail of aeration machine during grasslands football field
Close-up of aeration machine

Below are the different types of ways to aerate:

  • Core Aeration: A hollow tine is used to pull soil cores out of the ground. The cores are either broken up or removed from the surface. This is the best type of aeration because when the core is pulled, no soil is displaced—the soil is just simply removed. The downside, however, is that the core that was pulled up must be removed or broken up.
  • Solid Tine Aeration: This type of aeration is the next best form of aerating soil. As the name implies, a solid tine is used to poke the hole in the soil. The good thing about solid tine aeration is that there is little to no cleanup. The downside of solid tine aeration is that when the hole is made, the soil is displaced and essentially pushed around the side of the hole. Also, it is challenging to get deep penetration with a solid tine. If solid tine aeration is the only option, then the pros certainly outweigh the cons.
  • Star Aeration: This form is the least effective aeration method. However, something is better than nothing. A star aerator consists of a pull-behind apparatus with a row of star-looking blades. As it is pulled, the blades rotate, and the points jab into the soil surface. The pro to this method is that there’s very little cleanup involved, but the lack of penetration depth and decreased surface disruption are the major cons. Again, sometimes, something is better than nothing.
  • DryJect/Air Injection: These systems use air pressure to inject air and other materials into the soil profile. The air is pressurized and is blown down into the soil, which essentially blows a hole into the ground. DryJect systems actually fill the hole with porous materials. It’s a very effective aeration method, but there are pros and cons. The pros are that 1.) there is little to no cleanup or topdressing involved, and 2.) holes are made, and they reach the root zone. On the con side, these are specialized pieces of equipment and can either be costly to purchase or require you to hire a company that has one.
  • HydroJect: This is a very similar system to air injection. However, instead of using air, water is used to penetrate the soil profile and make a hole. Like air injection, there are similar pros and cons. On the pro side, there is little to no cleanup. The cons are that 1.) there must be a water source nearby, and 2.) it can be a pricy service or piece of equipment.

Verticutting

This is a common practice involving an implement attached to a tractor. A verticutter is a piece of equipment that has many rotating discs spaced about a couple of inches apart. As they spin, they cut into the turf and soil surface vertically. The debris is flung out the back and lies on the surface to be removed. This is an extremely effective way to thin bermudagrass and also remove thatch. An ample amount of time for cleanup and recovery is necessary, so be sure to budget extra time.

Fraze Mowing

Fraze mowing has been used in Europe on athletic surfaces for many years now, but only recently has it made its way into the US as a cultural practice. A fraze mower is an implement attached to a tractor that removes material off the playing surface. The key to this method is that bermudagrass has rhizomes that run under the soil surface. As all the other material is removed, the rhizomes remain and essentially regrow new bermudagrass plants. This is beneficial in many ways. Surface compaction can be alleviated, weed seeds that exist in the soil surface are removed, thatch is removed, the plant is effectively thinned out in order to regrow a thicker stand, and the surface can be leveled, to name a few.

Fraze mower in action, image courtesy of Alex Vaugh with River City Athletics

I have personally seen a football field get fraze mowed and be ready for the first game in five weeks’ time with only a few granular fertilizer applications for recovery. All the things listed above are the pros. There are, however, a few cons to be considered. This can be a costly practice, as it will most likely need to be outsourced. As seen in the picture, the equipment required to run one of these machines and to manage the cleanup is more than most have. It’s also important to make sure no activities happen on the field for at least a month after the fraze mowing has been done.

Topdressing Sand

All of the activities listed above are effective cultural practices, and topdressing sand can increase the effectiveness of each one. Essentially, the soil surface is opened up, and by adding sand, the sand is incorporated into the soil profile. Topdressing can occur without doing any of the above activities, as warm-season turf varieties positively respond, regardless. Just make sure to spread the sand evenly and either drag or water it into the turf canopy.

The above practices are the most common cultural practices on warm-season turf. A couple of reminders: 

  1. Be sure to plan ahead and work around any events that may be on the schedule. 
  2. It is possible to aerate and topdress multiple times during the peak growing season. However, the other activities are extremely invasive and require more recovery time. 

In order to speed up recovery time, I like to use the following products:

  • 22-3-11 50% Slow-Release w/ Armament is a great granular option to speed up recovery. An application directly after a cultural activity occurs will decrease the amount of recovery time. 
  • Foliar-Pak Grow-In is a great spray option. At a rate of 9-12 ounces per thousand square feet, the turf can heal quickly.

I hope this information helps. Please contact your nearest Advanced Turf Solutions representative for any questions or assistance.