Summer heat stress can be a serious problem for your lawn, especially in July and August. Heat, dry weather, and foot traffic are major stresses for most types of grass. Others problems, like weeds and bugs, can become worse when your lawn is already suffering. Changing a few simple habits, such as how short you cut the grass and the time of day you water it, can help the lawn to withstand the heat.
Grass and Heat Stress
Extended periods of heat and humidity, bright sunshine, and warm nights with no rain can add up to trouble. Warm-season grasses may love these conditions, but in the northern zones, cool-season grasses become stressed, wilted, and prone to disease. The heat and lack of rain call for more watering, but excessive moisture can lead to disease conditions. During the summer, grass utilizes the energy stored in its root system, sustaining the plant but shrinking the root system and making the turf vulnerable.
Steps to Treating Your Lawn for Heat
Spring preparations and summer maintenance can really pay off later in the season. Steps to creating an extensive root zone, maintaining a higher cut, and proper fertility will help allow the grass plants survive the dog days of summer.
Keep grass longer. Keeping grass a little longer in the heat of summer allows the roots extend deeper into the earth, preventing weeds from coming up and competing for water. And because the turf is denser, it requires less water. Try a blade height of about 4 inches during the summer months.
Sharpen mower blades. A sharp blade is always important but never more so than during hot summer months. Dull blades can cause grass to fray. Frayed grass is far more likely to brown than cleanly cut grass.
Mow early and less often. Mow less frequently and cut early in the day, or hold out until the sun begins to go down. Freshly cut grass is more likely to sustain damage in the hot sun, and keeping the lawn cool will cut down on those brown spots.
Consider mulch. Instead of bagging grass clippings, use a mulching mower. Allowing mulched grass to settle into the lawn will help trap moisture, keeping the lawn cooler and better hydrated. A mulching mower can be beneficial to the lawn all year long but is especially helpful for beating the summer heat.
Skip fertilizing. Depending on the type of grass, you can probably skip fertilizing during the summer. If your lawn is having trouble, have the soil tested first to see if there are deficiencies—before you get into fertilizers. If fertilizer makes sense, look at organic, time-release fertilizers to prevent burning your lawn.
Water wisely. Most lawns require about an inch of water per week to stay healthy. An irrigation system is ideal for lawn hydration, but no matter how the lawn is watered, time of day makes a difference. Despite what some say, watering during the hottest part of the day won’t damage grass, but rapid evaporation can be an issue. Deep, infrequent watering during morning hours allows moisture to be more efficiently absorbed by the root system