Brown patches in grass during summer are usually caused by drought stress, fungal disease, grub damage, heat and soil stress, or chemical burn. The key is identifying the cause before treating the problem, because applying the wrong product or treatment can make the damage worse.
The good news is that many summer brown patches are manageable and, depending on the cause, your lawn may recover once the underlying problem is addressed.
What Causes Brown Patches in Grass During Summer?
Summer can put significant stress on your lawn. Heat, humidity, dry weather, soil compaction, insects, and lawn disease can all cause grass to turn brown.
Here are five of the most common causes of brown patches in lawns during summer.
1. Drought Stress and Underwatering
Drought stress is one of the most common reasons grass turns brown during summer.
When your lawn does not receive enough water, cool-season grasses can enter dormancy as a survival mechanism. The grass may turn tan or straw-colored and feel dry or crunchy underfoot.
A few clues can help you determine whether drought is the problem:
- Try the footprint test: Walk across the lawn. If the grass springs back quickly, it is likely still adequately hydrated. If footprints remain visible, the lawn may be experiencing drought stress.
- Look at the pattern: Drought usually affects larger areas relatively evenly, although thin or sunny areas may turn brown first.
- Consider the timing: If the browning developed gradually after an extended dry period, drought is a likely explanation.
Cool-season grasses such as tall fescue and Kentucky bluegrass can sometimes remain dormant during extended summer heat and recover when temperatures cool and rainfall returns.
What should you do?
Water deeply rather than giving your lawn frequent, shallow watering. About 1 inch of water per week is a general target, with early-morning watering helping reduce evaporation.
2. Fungal Lawn Disease and Brown Patch
Not every brown lawn is suffering from a lack of water. Fungal disease is another common summer problem, particularly during hot and humid weather.
Brown patch disease is a fungal infection caused by Rhizoctonia solani. It can develop rapidly when conditions are warm, humid, and wet.
Look for these signs:
- Circular or irregular brown patches
- Darker borders around the edges of the affected area
- Rings or a "smoke ring" appearance
- Patches that expand quickly
- Damage appearing during hot, humid periods
Tall fescue, perennial ryegrass, and Kentucky bluegrass can be particularly susceptible.
Excessive summer nitrogen, poor air circulation, heavy thatch, and prolonged moisture can also increase disease pressure.
What should you do?
Avoid excessive nitrogen applications during periods of peak summer heat. Water early enough in the day that grass blades have time to dry, and address drainage or other conditions that keep the lawn excessively wet.
A properly timed seasonal fertilization program can also help maintain balanced lawn growth without creating unnecessary summer disease pressure.
3. Grub Damage Under the Surface
Sometimes the problem isn't visible until the damage is already underway beneath the lawn.
White grubs are the larval stage of beetles such as Japanese beetles and European chafers. They feed on grass roots beneath the soil surface and can cause brown, thinning areas as root damage increases.
One of the easiest ways to check for grub damage is to inspect the turf itself.
Try this simple test: Grab a section of brown turf and try to lift it like a piece of carpet.
If the turf lifts easily and has very few roots attached, grubs may be responsible.
Other signs include:
- Irregular rather than perfectly circular brown patches
- Turf that feels loose or spongy
- Birds, skunks, or raccoons digging in the lawn
- Brown areas that continue to expand
The timing of grub control is especially important. Preventive grub treatments are most effective when applied during the appropriate early-summer window, before significant root damage occurs.
TLC – The Lawn Company offers Grub Proofing as an optional service designed to help protect lawns during this critical period.
4. Heat Scorch and Soil Compaction
Some areas of your lawn experience more heat and stress than others.
Brown patches that consistently appear near driveways, sidewalks, patios, slopes, or high-traffic areas may be related to heat exposure or compacted soil.
Hard surfaces such as asphalt and concrete absorb and radiate heat, while compacted soil makes it harder for water and oxygen to reach the root zone.
Look for brown grass:
- Along pavement or hardscape
- At the top of slopes
- In areas where children or pets frequently play
- In areas where the soil feels hard or difficult to penetrate
Compaction can make drought stress worse and reduce the lawn's ability to recover from summer conditions.
What should you do?
Core aeration can help relieve compacted soil by creating channels for air, water, and nutrients to reach the roots. For cool-season lawns, fall is generally an ideal time for aeration.
5. Chemical Burn from Fertilizer or Herbicide
Brown spots can also develop after a lawn receives too much fertilizer or an improperly applied herbicide.
Chemical damage can sometimes look similar to disease or drought stress, but the pattern can provide a clue.
For example:
- Fertilizer burn may follow the path of a spreader.
- Herbicide damage may appear as irregular yellow or brown areas.
- Damage that appears shortly after a lawn treatment may indicate a chemical issue.
Applying too much fertilizer, particularly during stressful summer conditions, can damage turf.
If you suspect a product was accidentally overapplied, watering the affected area thoroughly may help dilute the material if the problem is caught early. The extent of recovery depends on how much tissue was damaged and whether the plant crown survived.
How Can You Tell What Is Causing Your Brown Patches?
Before treating brown grass, take a closer look at the shape, soil, roots, and timing of the damage.
Start With the Shape of the Brown Patch
The pattern can provide an important clue.
- Circular patches with darker borders: May indicate fungal disease such as brown patch.
- Uniform straw-colored grass: More likely to be drought stress or dormancy.
- Irregular patches with loose turf: May indicate grub damage.
- Lines or streaks: Can point toward fertilizer application patterns.
- Brown areas beside pavement: May be related to heat stress or soil compaction.
Check the Roots and Soil
Pull a small section of turf from the damaged area and compare it with healthy grass nearby.
Healthy roots should be firm and well-established. Short, dry roots can indicate drought stress, while turf with very little root attachment can point toward grub damage.
You can also check whether the soil feels extremely dry, hard, or compacted.
Think About When the Damage Started
Timing can be another valuable diagnostic clue.
Brown patches that appear during hot, humid weather in July or August may be associated with fungal disease or insect activity.
Brown grass that develops gradually after a prolonged dry period is more consistent with drought stress.
Damage that appears within a few days of a lawn treatment may be related to chemical injury.
When you're unsure, avoid treating the lawn based on appearance alone. Correctly identifying the problem is the first step toward choosing the right solution.
How Do You Fix Brown Patches And Keep Them From Coming Back?
Treating the visible brown patch is only part of the solution.
If the same areas repeatedly turn brown every summer, there may be an underlying issue involving soil compaction, drainage, fertility, insects, or the timing of lawn care applications.
Keep Fertilization and Weed Control on a Seasonal Schedule
Your lawn does not need the same treatment throughout the year.
TLC – The Lawn Company's Annual Service Program uses five seasonal visits with fertilizer, weed control, and surface insect controls applied at the appropriate time and levels.
This seasonal approach helps support your lawn throughout changing growing conditions rather than relying on one large summer application.
Learn more about TLC's full lawn care service program.
Consider Grub Proofing Before Damage Appears
If grubs are a recurring problem, prevention is often more effective than waiting until visible damage appears.
The timing of preventive grub treatments matters because the treatment window occurs before homeowners typically notice the problem.
Adding Grub Proofing to your annual lawn care program can help ensure that the appropriate application is made at the right time.
Explore TLC's optional lawn care services.
Aerate and Overseed in the Fall
If compacted soil or thin turf contributes to your summer problems, fall is a good time to strengthen the lawn.
Core aeration helps relieve compaction and improves the movement of water and nutrients into the root zone. Overseeding can then help fill in thin areas with new grass.
TLC offers both Core Aeration and Core Aeration with Overseeding as optional services.
Strengthening thin and compacted areas in the fall can help your lawn better handle the heat and stress of the following summer.
Choose a Lawn Care Program Built Around Your Region
Your lawn responds to local weather, soil conditions, grass types, and pest pressure.
TLC – The Lawn Company has more than 40 years of experience providing lawn care across Massachusetts, New Hampshire, Connecticut, Rhode Island, Pennsylvania, New Jersey, Delaware, Maryland, Virginia, Michigan, and Ohio.
That regional experience helps determine what should be applied, when it should be applied, and how your lawn should be managed throughout the season.
TLC also offers a service guarantee and a price-match guarantee.
Check TLC's service areas to see if your town is covered.
When Should You Call a Lawn Care Professional?
If you cannot determine why your grass is turning brown, a professional lawn care company can help identify the likely cause and recommend the appropriate next step.
When contacting a lawn care professional, be prepared to explain:
- What shape the brown patches are
- When you first noticed them
- Whether they are spreading
- Whether the grass lifts easily
- How much rain or irrigation the lawn has received
- Whether fertilizer, herbicide, or another product was recently applied
These details can help narrow down the cause and prevent unnecessary treatments.
Keep Your Lawn Healthy Through Summer
Brown patches in grass can be frustrating, but they do not always mean your lawn is permanently damaged.
Drought, fungal disease, grubs, heat stress, compaction, and chemical damage can all create brown areas, and each problem requires a different approach.
The most important thing is to identify the cause before treating the symptom.
A seasonal lawn care program, proper watering, timely grub protection, and fall aeration can all help your lawn stay healthier and better prepared for summer stress.
Give Your Lawn The Care It Needs
Request a Quote and let TLC – The Lawn Company help keep your lawn lush, green, and healthy.
