The 2025 golf season in the Chicago area was one for the record books, and not in a good way from the point of view of our golf course superintendents. Every potential agronomic challenge was thrown at them.
The playing surfaces for golf in our area are mostly dependent on cool-season grasses such as creeping bentgrass, Poa annua, fescues and Kentucky bluegrass. These grasses are sensitive to temperature extremes. When the weather allows for good growth, our superintendents can focus on delivering the best possible playing conditions - firm, smooth and fast.
The growing season of 2025 was a story of weather extremes - too cold, too hot, too much rain, too little rain, too humid or too dry. Plant stress was commonplace, which meant conditions were perfect for disease, pests and weeds.
Superintendents in the Chicago District were on the defensive for the entire golf growing season. Practices that were commonly employed to maintain healthy turf included raising mowing heights (slower greens), a more frequent use of automatic and hand irrigation (softer surfaces), aerification as needed to improve rooting (bumpy surfaces) and more frequent applications of fungicides, herbicides and insecticides (increased expense).
WINTER
Our winter was colder and drier than normal. This started our growing year with less than normal moisture in the ground with some visible desiccation of greens. We ended winter with a moisture deficit. Chicago had so little snow that it ranked as one of the least snowy winters ever recorded.
SPRING
Early spring had a few warm moments and normal rain. However, as the season progressed, it remained cooler than normal, and after some early April showers, conditions began to dry out. It could be characterized as a slow spring. This pattern of cool and dry continued through May, falling short of the air temperatures and soil temperatures necessary to support healthy creeping bentgrass. Greens in the Chicago area did not really begin to grow until mid-June, which by any standard is quite late.
SUMMER
The 2025 season brought an abrupt transition from May to July, skipping the crucial month of June that is vital for creeping bentgrass root development. The resulting heat stress led to poor rooting, especially so in greens at low mowing heights, during July. The end of June through July was one of the hottest on record, with oppressive heat and humidity adding up to 17 days of 90-degree-plus highs (see chart above).
And every time we had a break in the heat and humidity, it was short-lived.
August cooled a bit and brought a brief period of rain, but September came in warmer and drier than normal. It was the seventh driest September in history.
Because the conditions were not good for our fairways and greens, it meant normal plant health and plant defenses took a back seat. As a result, weeds and pests thrived. Some examples include:
● Annual bluegrass weevils found their way to courses in Chicago’s north suburbs by late spring. Lance nematodes attacked the roots of our greens in summer, while white grubs feasted on fairways and rough during the fall
● Fungal diseases such as dollar spot, brown patch, fairy ring, Pythium blight, summer patch and anthracnose were fed by the heat and humidity
● Poor bentgrass rooting all season provided thin areas, which allowed weeds such as crabgrass, broadleaf weeds, clover, nutsedge, oxalis and buckthorn plantain to thrive.
FALL
This is normally a time for turf recovery and often delivers some of the best playing conditions of the year. Not this year. September continued the trend of dry and warm weather. The resulting drought stress slowed turf recovery normally seen in the fall. More watering and irrigation were needed than is typical at this time of year. Superintendents worked hard through September and October to support turf recovery. Examples include aeration of tees, fairways and greens, replacing affected areas with sod or seed and nonstop watering. It may not be the perfect playing conditions we’ve come to expect, but it is all with an eye on getting ready for the 2026 season.
In summary, our superintendents were faced with a historically difficult growing season in 2025, with a similar hot summer not seen since 2012. Their hard work and experience came to the fore in delivering to us the best possible playing surfaces. Take a moment to let them know you are aware of the challenges and thank them for all that they do, and hope for a better growing season in 2026 that eases their burden.
Steve Green is a member of the CDGA Green Committee. He has been a Blue Coat since 2017.
