Field Insights Blog | GreenCast | Syngenta
Field Insights Blog | GreenCast | Syngenta

Primo: Recognizing the Obvious

“It’s obvious.”  That phrase has gotten more people into trouble or embarrassment than most would omit. Obvious refers to something that is found or spoken on a routine basis. Yet, what is obvious is often invisible to a simple explanation because we assume everyone knows what it is or means. 


Figure 1.  Application of Primo Maxx being made to a putting green

In golf course management, we use terms and acronyms on a daily basis that we assume everyone, especially our staff and interns, know.   As an example, one of the most common acronyms used in turf is PGR. PGRs are commonly used in everyday maintenance of both cool- and warm-season turf grasses, yet if you were to ask your staff and crew what PGR stands for, how many could tell you?  

PGR stands for plant growth regulator, but when I have asked students, for example, I have gotten answers like “I don’t know” or “Primo Growth Regulator”.  Although not correct, the last phrase is a catchy one. To test you a little more, the acronym TGR stands for turf growth regulator.  

​​​​​​​I’ve heard some refer to TGR as “Trimmit Growth Regulator”.  Actually the term TGR was associated with a 1980s Scotts product called Scotts TGR. The active ingredient in the product was paclobutrazol, now marketed as Syngenta’s Trimmit®.  Scotts TGR which also included a fertilizer as part of the product was marketed on high quality turf as a Poa annua suppressor on creeping bentgrass fairway.

A word or acronym in itself may not be critical to managing turf, but the why and how is. Primo Maxx® is an integral part of most golf course management programs and has been for several decades.  When trinexapac-ethyl (Primo Maxx) came to market in 1992, it changed the PGR market and how golf courses are managed.

Primo was released as a PGR to be used on golf courses to be applied throughout the growing season.  Prior to Primo Maxx, PGR use was often 1 or 2 applications to a moderate to low high cut turf that was difficult to mow.  In golf, Primo Maxx was marketed as a means of suppressing growth so that you could mow less frequently and reduce the wear and tear on mowing units. Prior use of PGRs were sold on the idea you would not mow for 4 to 6 weeks. Primo Maxx - combined with mowing - provided a superior cut and quality to the turf. And that was just the start.

Since Primo’s release I do not know of another product that has been studied more by turfgrass researchers. Just about any question that a golf course superintendent might have about Primo has been answered with research.   Whether you want to know the impact on root growth, disease incidence, winter overseeding or preconditioning for summer stress, to name a few, it has been researched.


Figure 2.  Primo Maxx has been thoroughly tested and researched.


One of the major changes I’ve seen with Primo Maxx is that the rates have dropped and application frequency has increased. Originally Primo MAXX would be applied at 0.5 oz./1,000 ft.2 on a 30-day basis. Now, especially on greens the rate is often 0.125 oz./1,000 ft.2 every 7 days. The shorter interval gives a more uniform release. 

Primo Maxx originally - and I’m using my recollection as a source - was formulated as an EC (emulsifiable concentrate) or as a WSB (water soluble bag).  The Primo WSB was twice the active ingredient of the current product.  Just the improvement in formulation to a Maxx has made the product easier and safer to use.  

Since 1992 the number of staff and interns who have been exposed and grown up using Primo Maxx is too numerous to count.  As these professionals have moved to positions of decision makers often their use of a product like Primo is not based on an understanding of the product but because their previous boss used it. 

​​​​​​​A part of leadership and mentoring is recognizing the obvious and not assuming your staff and interns know what you know.  They may be too embarrassed to ask what appears to be the obvious.  The obvious, in this example is Primo Maxx , and it's never really noticed until someone takes the time to point it out and explain why it is used.



About the author

Dr. Karl Danneberger is a professor of Turfgrass Science at The Ohio State University. Dr. Danneberger's contact information can be found here. You may also follow Dr. Danneberger on Twitter:

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