Large Patch Fungus Treatment in Pinellas County, Florida

Large Patch Fungus Can Damage Your Lawn—Fast

When the weather turns damp and cool, your lawn is at risk for more than just slower growth—it’s vulnerable to Large Patch Fungus, a seasonal turf disease that strikes warm-season grasses across Pinellas County, Florida. If you’re seeing discolored rings or yellowing patches that seem to spread overnight, this aggressive fungus may already be active in your yard.

At Eagle Lawn and Pest Control, we specialize in diagnosing, treating, and preventing large patch before it causes long-term damage. We work with homeowners and businesses across Clearwater, St. Petersburg, Largo, and every corner of the county to keep lawns fungus-free and healthy year-round.

📞 Call us today at 727-953-8180 to schedule your lawn inspection and stop Large Patch in its tracks.

What Is Large Patch Fungus?

Large Patch, caused by the Rhizoctonia solani fungus, is one of the most destructive cool-season turf diseases in Florida. It’s especially active when nighttime temperatures drop between 50 and 75°F and damp conditions persist. Unlike some lawn diseases that are hard to detect, Large Patch is easy to spot—but difficult to stop without professional care.

What It Looks Like

Large Patch creates irregular, expanding circles that may start small but can quickly grow to several feet in diameter. One of its defining features is a yellow-orange halo around the edges of affected areas, especially noticeable in early morning dew. While this disease mainly attacks the leaves of grass rather than the roots, the damage to appearance and density can be significant.

What Types of Grass Are Affected

Large Patch primarily targets:

  • St. Augustine Grass
  • Zoysia Grass
  • Bermuda Grass (occasionally)

These turf types are common throughout Florida and are especially susceptible during the cooler months, often from late fall through early spring.

What Causes Large Patch Fungus?

The right (or wrong) combination of moisture, mowing, and maintenance can make your lawn an open invitation for fungal growth. Here are the most common causes:

Main Causes of Large Patch Fungus

  • Overwatering – Cooler weather means your lawn needs less water. Watering too frequently, especially in the evening, keeps the turf damp and fungus-friendly.
  • Excessive Thatch—Thatch (a layer of dead and living grass tissue) holds moisture and heat, creating the ideal habitat for fungi. Keep thatch to less than ¾ inch.
  • Improper Mowing—Mowing too short weakens your lawn and can cause thatch to build up. Maintain the recommended height for your turf type.
  • Overfertilization—Applying nitrogen-heavy fertilizer in the fall can trigger fungal activity. Fertilization should be strategic, not excessive.

Our Proven Large Patch Treatment Program

At Eagle Lawn and Pest Control, we take a holistic approach to fungus management. Our program doesn’t just kill the active fungus—it prevents it from returning by addressing soil health, drainage, and turf resilience.

Our Step-by-Step Fungus Management Plan

  • Professional Fungicide Applications—Applied at the right time for maximum effectiveness
  • Soil & Drainage Corrections – Eliminate poor runoff and compaction
  • Balanced Fertilization – Feed your lawn the nutrients it needs—without overdoing it.
  • Lawn Care Education – We provide custom mowing, watering, and seasonal advice to support ongoing health.

Ways to Prevent Large Patch Fungus

You don’t have to wait for fungal damage to show up. With proper care, you can keep Large Patch from ever gaining a foothold in your yard.

Prevention Tips From Eagle Lawn and Pest Control:

  • Water in the early morning to prevent prolonged turf wetness
  • Adjust irrigation schedules as the weather cools.
  • Keep thatch layers under control
  • Avoid late-season nitrogen spikes in fertilization.
  • Maintain consistent mowing height and blade sharpness

Our goal is to make sure Large Patch never gets the chance to return.

Service Area: Serving All of Pinellas County, Florida

We proudly protect lawns in all 24 municipalities throughout Pinellas County, including

  • Clearwater
  • Largo
  • St. Petersburg
  • Seminole
  • Dunedin
  • Palm Harbor
  • Tarpon Springs
  • Gulfport
  • Indian Rocks Beach
  • Belleair
  • Safety Harbor
  • Treasure Island
  • And more

Don't Let a Large Patch Ruin Your Winter Lawn

Large Patch is preventable—and treatable—but only if caught early and managed correctly. If you see yellow halos, spreading patches, or thinning grass, don’t ignore it. Let Eagle Lawn and Pest Control help you take back control of your turf.

📞 Call us today at 727-953-8180 or request your free lawn inspection online.
We’ll diagnose the issue, treat the disease, and help ensure your lawn stays healthy through every season.