Over the last decade, the use of PGR's has become the standard rather than the exception in putting green management. But with all the use, can turf become resistant to these products? While I have never heard of turf developing resistance, I have noticed that even with increased rates of Primo, we are not having the desired level of regulation as in years past. In response, I have begun using paclobutrazol or Trimmit along with Primo in our program. While there is some discoloration, and the Poa does not have the color as with using strictly the Primo, the playability is exceptional, with the Bent and Poa growing at the same rates. I do however think that this product should be used during actively growing seasons in order to prevent weakening of the Poa. Stay tuned!
