An expanding brown area in the lawn can make you reach for the irrigation controller. In cooler, wetter conditions, however, some patches may involve large patch disease.
That possibility is a reason to investigate. A brown circle alone cannot confirm the diagnosis.
Record the pattern
Take a wide photograph that shows the patch and the surrounding lawn. Note whether it is expanding, where irrigation reaches it and whether the area stays wet longer than neighboring turf.
Photograph the edge as well as the center. Keep dates so a professional can see how the problem changed.
Consider large patch among the possibilities
UF/IFAS describes large patch as a disease affecting warm-season turf, with St. Augustinegrass and zoysiagrass particularly susceptible. Favorable conditions include prolonged moisture and cooler temperatures.
Affected turf can develop yellow or brown patches that expand. These signs need to be considered alongside other causes, including insect damage, water stress and different diseases.
Review conditions before adding inputs
Check for unnecessary irrigation and places where water accumulates. Excess moisture and inappropriate nitrogen application can favor the disease.
Avoid making a large schedule increase simply because the lawn has changed color. Equally, do not assume every affected area should receive the same treatment.
Diagnose before treating
Use a qualified professional or Extension diagnostic service to determine the cause and appropriate response. Similar-looking problems may need different management.
If treatment is recommended, it should follow the current product label, site needs and applicable requirements. Improving the conditions around the turf remains part of the plan.
Watch recovery over time
Keep photographs and care records after changes are made. Turf recovery depends on the injury and growing conditions; immediate greening is not a useful promise.
Give the lawn a proper diagnosis: Ask TLC about a Landscape Assessment or Garden Stewardship.
Sources: UF/IFAS Large Patch, Gardening Solutions large patch.
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