Originally published by Golf Course Industry on Nov. 29, 2018
How picking the proper polymer-coated fertilizer can help turf handle wacky spring weather.
There is no downplaying the importance of quality polymer coatings in fertility choices for today’s superintendents, especially when coming out of winter and a spring jolt is needed. No longer is it just simply choosing the sources of your fertilization, but now it’s become increasingly important to consider and choose the coating as well.
Longevity is the key word with today’s formulations. Along with longevity, another buzz term in the industry today is Enhanced Efficiency Fertilizers (EEFs). Due to their longevity, EEFs keep the cost down as well as help the environment by reducing leaching, denitrification, runoff and volatilization, allowing more nutrients to be taken up by the plant.
Koch Turf & Ornamental (Koch) has seen the need to provide superintendents and other turf professionals fertility options that fit into this new enhanced efficiency mindset. “We are one of the largest manufacturers today providing quality controlled-release products,” Koch Turf & Ornamental senior regional sales manager Andy Drohen says. “Koch currently offers various nitrogen (N) products that can fit almost any niche or circumstance out there.”
One of these products, DURATION CR®, offers controlled-release that helps superintendents begin the growing season by taking control of nutrient feeding. “DURATION CR can help take the stress off superintendents’ spring fertility planning,” Drohen says.
“With traditional slow-release fertilizers, you can’t really control the timing of release,” he adds. “There are too many variables. This is why superintendents now tend to rely on the controlled-release technology.
“We never truly know what kind of spring we are going to have. It can be difficult to get out on the course to spread fertilizers if it’s too wet and spongy. Superintendents can apply a polymer-coated product in the fall, usually at a rate anywhere from 1 to 2 pounds of N per 1,000 following fall aerification. This will not only give them good recovery after a long, tough summer – as well as harden off the plants as winter approaches — but it also will leave some of the fertilizer to sit under the snow all winter and be ready to release come spring time. Because DURATION CR's release is dependent on temperature, it slows down and stops as the cold weather sets in and starts to release again once the spring temps warm up.”
A key to this controlled release is the technology behind reacted layer coating (RLC).
“We are the leaders here,” Drohen says. “RLC involves two monomers. The first, monomer ‘A,’ is applied to the substrate, such as urea. It then reacts to form a nice, tight bond with the urea with no air pockets (air pockets can break during manufacturing or shipping or even during spreading, basically turning an inferior product into straight urea at application). The second, monomer ‘B,’ is applied and reacts with monomer ‘A’ to form a hard, durable polymer that won’t break during nitrogen release in the field.”
This is where Koch, at the manufacturing stage, can vary the coating thickness for different products and uses. Basically, thicker coatings for warmer weather and thinner coatings for cooler temps. Utilizing an ultra-thin but ultra-tough polyurethane coating along with granules that are round and uniformly sized can further help turf handle weather swings. The thickness of the coating can extend the longevity of a product anywhere from eight to 52 weeks.
“By varying that coating thickness, depending on what part of the world you are applying or what season you are heading into, you can basically get the nitrogen release to mirror the growth curve of the turfgrass plants,” Drohen says.
Fertilization in unpredictable weather can be tricky. But proper fertilizer selection can make the task less daunting. “No matter what type of unpredictable weather folks may see, Koch can provide plant nutrition when golf course superintendents most need it,” Drohen says.