A Homeowner’s Guide for Columbus, Ohio
It’s the middle of summer. You step outside with your morning coffee, expecting to see your lush green lawn—and instead, you spot yellow patches, odd discoloration, or maybe even something fuzzy growing on your grass. Don’t panic: chances are, your lawn is dealing with a common turf disease, and with the right knowledge and treatment, you can get things back on track fast.
If you live in Columbus or anywhere in Central Ohio, your lawn is most likely made up of cool-season grasses like Kentucky bluegrass, tall fescue, or perennial ryegrass. These grasses are resilient, but they’re not immune to disease—especially when our local weather brings humidity, heavy rain, and high heat.
Let’s walk through the most common lawn diseases in our region, how to recognize them, and what to do about them.
Brown Patch
What it looks like: Large, circular patches of brown or yellow grass with slightly darker edges—sometimes called “smoke rings.”
Brown patch is one of the most common summer lawn diseases in Ohio. It thrives in hot, humid weather and targets tall fescue and ryegrass. It often appears after over-fertilizing, mowing wet grass, or watering in the evening, when moisture hangs around overnight.
What to do:
Mow high, water early in the morning, and avoid heavy nitrogen applications during hot weather. In severe cases, a fungicide may be needed, especially if the disease continues to spread.
Dollar Spot
What it looks like: Small, round, tan patches about the size of a silver dollar—eventually merging into larger areas.
Dollar spot loves warm days and cool nights, which makes late spring and early fall prime time in Central Ohio. The grass blades may show tan lesions with reddish-brown edges, giving a bleached appearance.
What to do:
Boost your lawn’s nitrogen (but don’t overdo it), water deeply but less often, and mow regularly with a sharp blade. Most cases clear up with improved lawn care; fungicides are rarely needed unless it’s widespread.
Red Thread
What it looks like: Thin red or pink strands growing from the grass blades, giving your lawn a reddish cast.
Red thread usually shows up in nutrient-poor soil and affects perennial ryegrass more than other types. It’s most active in cool, damp conditions like early spring or fall.
What to do:
A mild fertilizer boost usually clears this up. Red thread is more cosmetic than damaging, and your lawn should recover on its own once nutrition improves.
Rust
What it looks like: Orange or yellow powdery dust on your grass—and your shoes or mower after walking across the lawn.
Rust often appears in late summer when grass growth slows down. It targets bluegrass and ryegrass, making the blades look dusty and weak.
What to do:
Start mowing more often and apply a light fertilizer to encourage new growth. Rust fades on its own as your lawn bounces back. In most cases, there’s no need for chemical treatment.
Pythium Blight
What it looks like: Greasy, matted, water-soaked patches that turn brown and die—often very quickly.
This is one of the most aggressive lawn diseases and can destroy large areas within days. It thrives in overwatered, poorly drained lawns, especially during hot, humid weather.
What to do:
Act fast. Reduce watering, improve drainage, and increase airflow. You’ll likely need a fungicide specifically designed for Pythium. Severely damaged areas may need to be reseeded.
Snow Mold
What it looks like: Circular, matted patches of dead grass after the snow melts—often gray or pink in color.
While not as common in Columbus as in northern Ohio, snow mold can appear in early spring after a long, snowy winter. It affects lawns that were left with leaves or debris going into winter.
What to do:
Rake out affected areas to help the grass dry and recover. Avoid fertilizing late in the fall and keep the lawn clear of debris. Most cases resolve without chemical treatment.
Powdery Mildew
What it looks like: White or gray powder coating grass blades—like someone dusted your lawn with flour.
This tends to appear in shaded, poorly ventilated lawns, often in areas under dense tree cover or near fences and buildings.
What to do:
Improve air circulation and sunlight exposure if possible. Trimming trees or switching to a more shade-tolerant grass blend can help. Fungicides are rarely necessary unless it becomes chronic.
What Causes Lawn Disease in the First Place?
Lawn diseases are usually the result of stressful growing conditions—think compacted soil, overwatering, drought, too much fertilizer, or simply poor air circulation. Columbus’s humid summers, rainy springs, and clay-heavy soil create a perfect storm for disease when lawns aren’t well maintained.
The good news? Healthy, well-managed lawns are much more disease-resistant. That’s why proper mowing, watering, fertilizing, and aerating matter just as much as treatment once a problem appears.
Prevention Is the Best Cure
You don’t need a chemical solution for every lawn issue. In fact, many diseases can be prevented—or cleared up—by adjusting your maintenance habits:
- Mow at the proper height (usually 3–4 inches for cool-season grass)
- Water deeply and infrequently (preferably in the early morning)
- Aerate compacted soil once a year
- Use slow-release fertilizers with balanced nutrients
- Keep your mower blades sharp and clean
By improving your lawn’s overall health, you’ll reduce the chance of disease taking hold in the first place.
Soil Health Matters More Than You Think
Your lawn’s health starts underground. Clay soils—which are common in Franklin County—tend to compact easily, cutting off air and water to the root zone. This makes your turf more vulnerable to disease.
A simple soil test can tell you a lot. If your lawn’s pH is off or nutrient levels are low, fixing those problems can improve your grass’s resistance naturally.
Not Sure What You’re Dealing With?
Sometimes, it’s hard to tell whether you’re facing a lawn disease, drought stress, pet damage, or insect activity—they can all look similar. If your efforts aren’t working, a professional lawn diagnosis might save you time, money, and stress.
Experienced lawn care providers can help you:
- Accurately identify the problem
- Apply targeted treatments (only if necessary)
- Build a long-term care plan that prevents future issues
Final Thoughts
Lawn diseases are frustrating—but they’re also manageable. By learning to recognize the signs early and making smart lawn care choices, you can protect your turf from most problems before they take over. For Columbus homeowners, focusing on soil health, seasonal maintenance, and early detection is the key to keeping your lawn healthy year-round.
Need help identifying or treating a lawn issue? We’re here to help—whether it’s a quick fix or a full lawn recovery plan.
