It seems like a while ago, but it was only 5 weeks ago that we were experiencing a fairly gentle start to summer. We even had a few days in June with highs in the 60’s and it made for pretty easy lawn growing weather.

Flip the calendar to mid-July and it has been a different story. All of us knew summer would arrive eventually, and now we are dealing with high temperature and high humidity conditions very typical of mid-summer in Maryland.

For those with warm-season grass lawns, like zoysiagrass, the lawn should be thriving, as these grasses enjoy the heat. For most homeowners who have tall fescue, summer is always a challenge to minimize the heat stress and disease pressure on the lawn. Tall fescue is best adapted to growth when low temperatures are in the 50’s and highs are in the 70’s to around 80. Through July, we have had many days near or above 90 and many nights where the temperature didn’t drop below 70.

There are a few different reasons your tall fescue lawn may be going brown or declining this time of year—the most common are related to drought stress, soils that are too wet, or brown patch disease. Typically, growth slows down a bit in mid-summer anyway as part of a grass’s natural growth cycle as it uses more carbohydrates (food reserves) than it makes. So when the grass does experience stress or disease it is slower to recover. Drought-stressed plants exhibit a purple to grayish hue, a narrower or “curled up” leaf blade, and footprints are visible for several minutes after walking across a drought-stressed area. Continue reading →