September Heatwave: A Tough Stretch for the Greens

Managing Bentgrass greens through a tough summer is always a balancing act. Interestingly, pure heat isn't actually our biggest troublemaker. The real issues start when intense heat pairs up with high humidity and heavy, poorly timed rain. Because this summer was drier than normal, we were actually able to keep the turf quite manageable. We made it all the way to late August and completed our aerification during one of the most perfect, moderate weeks I can recall, with daytime highs in the mid-80s and nighttime lows in the 60s.

As a Superintendent, if you hit the end of August with healthy greens, you generally feel great about the season. But the battle isn’t over until autumn truly arrives, and September has been incredibly tough on our Bentgrass this year. According to the National Weather Service, this September has started out as the third hottest on record.

6 Green

The month started with brutal weather—temperatures in the mid-to-high 90s all week and heat indexes hitting 105+. That heatwave wrapped up with a 3.5-inch Friday evening downpour. Within a few days, the trapped moisture forced the greens into an anaerobic (oxygen-depleted) state, leading to some yellowing and thinning. The hot weather didn't let up either; the next week and a half brought more 90 degree days, another inch of rain and severe winds that knocked down trees throughout the neighborhood.

The difficult to swallow news is Member Guest starts tomorrow and it is not the product we worked so hard for all summer to present in mid-September. The hopeful news is that the greens have stabilized. However, they have thinned and are still in a very fragile state. To fully turn things around, we just need some classic fall weather: daytime temps in the low 80s and crisp 60-degree nights. This drop is crucial to lower soil temperatures significantly, which will give the plants the opportunity to initiate new root growth. When the roots are happy and growing, a great playing surface is never far behind.

How You Can Help Us Protect the Turf 

While we wait for Mother Nature to cooperate, the greens need a little extra care from all of us. You can directly help their recovery by following these quick practices during your round:

• Fix ball marks carefully: Thinned, fragile turf takes much longer to heal from impact. A clean repair helps prevent bare spots.
• Watch your step: Avoid twisting your cleats or dragging your feet on the green surfaces, as the weak root systems can easily tear right now.

Thank you for your patience and support as we guide the course through this difficult stretch of weather!