Mowing Adds to Lawns’ Hot-Weather Stress
OLATHE, Kan. – Sometimes good advice is a relief.
“Be slow to mow during extremely hot weather. Mowing will simply add to your lawn’s stress,” said Rodney St. John, turfgrass specialist with K-State Research and Extension.
Even warm-season Bermuda, zoysia, and buffalograss lawns suffer when air temperatures reach the high 90s (F) and triple-digits, St. John warned.
Unless cool-season turfs have entered summer dormancy, though, high temperatures can quickly create stress that has lawns struggling to survive. That’s when irrigating is vital and mowing is about the last thing tall fescue and Kentucky bluegrass need.
“The good news is: Lawn grasses don’t grow much in extreme hot weather,” he said. “With luck, you can simply put off mowing until things cool off a bit.
“The upper 80s or lower 90s are the best point at which to resume your normal mowing schedule. Even then, however, you’d do well to set your mower at the high end of your turf’s cutting-height range. Then, keep it high until fall arrives.”
The high end of warm-season turfs’ recommended cutting range is about 2 inches, St. John said. Cool-season turfs’ range peaks at 3.75 to 4 inches tall.
No matter the turf or temperature, though, another bit of research-proven advice is to mow whenever lawns grow a third taller than their recommended cutting height.
“Removing much more leaf tissue than that can send turf into a kind of shock. Frequently cutting too much off can change a healthy lawn into thin, stemmy grass with a poor root system and space for weeds,” he said.
Mowing is a major lawn-management tool that affects turf health and performance, St. John added. Lawn owners can learn about its most effective uses at their nearest Extension office or online at Mowing Your Lawn.
K-State Research and Extension is a short name for the Kansas State University Agricultural Experiment Station and Cooperative Extension Service, a program designed to generate and distribute useful knowledge for the well-being of Kansans. Supported by county, state, federal and private funds, the program has county Extension offices, experiment fields, area Extension offices and regional research centers statewide. Its headquarters is on the K-State campus, Manhattan.
Story by: Kathleen Wardkward@ksu.eduK-State Research & Extension News
Rodney St. John is at 913-856-2335 ext. 110