A friend of mine asked me what to do to his lawn in this crazy summer heat. His lawn, as well as mine, looks like a typical summer fescue lawn — large areas that are straw brown. Fescue is a cool-season grass originating in Europe that grows best in the fall and spring.

When temperatures climb above 85 degrees, growth declines and the grass becomes semi-dormant. Irrigating cool-season lawns during hot summer days can be tricky.

If you cannot irrigate your lawn during long periods of drought, allow the established lawn to go dormant, turning straw brown often in streaks. Most of the fescue grass is not dead, it’s just gone dormant until cooler fall weather and rainfall returns. It is important for cool-season lawns to be irrigated during extended hot, dry weather, or it will eventually die. Fescue lawns need about 1.5 inches of water per week during hot, dry weather. When cooler temperatures and rain return in the fall, fescue greens up and returns to normal growth.

Those who have an irrigation system and want a non-dormant lawn must continue to irrigate on a regular basis. Water fescue lawns when the grass looks blue-gray and you can see footprints on it. Be sure to irrigate lawns in the early morning to discourage disease and increase watering effi­ciency. It is not recommended to irrigate lawns during the heat of the day. Irrigate your lawn slowly, wetting the soil to a depth of 4 to 6 inches, avoiding water runoff. Avoid light, frequent watering since this type of practice encourages foliar diseases and shallow root growth.

Continue to maintain your lawn with weed control as needed and mow fescue grass at a height of 4 inches, preferably when the dew is not present, since wet grass encourages disease problems.

Darrell Blackwelder is the retired horticulture agent and director with the North Carolina Cooperative Extension Service in Rowan County. Contact him at deblackw@ncsu.edu.