Large Patch (Brown Patch) in North Florida Lawns
Large patch, often called brown patch, is the disease behind those spreading yellow-brown circles that show up in North Florida lawns once the weather turns cool and wet. It looks alarming, but it is manageable, and the grass usually recovers.
How to spot it
- Roughly circular patches of yellow to tan grass, from a foot to many feet across, that slowly widen
- A darker, orange-tinged ring around the edge of an active patch
- Blades that pull away easily from the runner, with rotted bases
- Shows up in the cool, wet stretch, roughly November through May, not in the heat of summer
The North Florida cause
Large patch is caused by the soil fungus Rhizoctonia solani, which turns active in cool, moist conditions below about 80 degrees. In North Florida that is roughly November through May. It hits St. Augustine and Zoysia hardest, and it is made worse by overwatering, too much fall nitrogen, poor drainage, and heavy thatch.
Sources: UF/IFAS Gardening Solutions, "Large Patch"; UF/IFAS LH010.
Cultural fixes that work
- Water only in the early morning, never in the evening, so the grass is not wet overnight
- Ease off nitrogen fertilizer in fall, when the disease is getting started
- Improve drainage in low, soggy spots where it keeps coming back
- Mow at the right height for your grass and keep thatch in check so air and light reach the soil
Where GR comes in
We keep your lawn on a steady mowing schedule at the correct height, which is one of the best defenses against a stressed, disease-prone lawn, and we can water-schedule advice around the disease. Where a patch has fully died out and left bare ground, we re-sod the area so it fills back in.
Straight talk: We do not apply fungicides or any chemical disease treatment, that is licensed work we do not do. We manage large patch the way UF/IFAS recommends first: cultural practices and, where needed, re-sodding the dead spots.
Large Patch (Brown Patch) in North Florida Lawns FAQ
Is large patch the same as brown patch?
Yes. "Brown patch" is the older common name, and UF/IFAS now calls the warm-season-grass version "large patch." They are the same disease on St. Augustine and Zoysia.
Will my grass grow back?
Usually. Large patch attacks the leaves and stems, not always the roots, so healthy turf often greens back up when the weather warms and the cultural issues are fixed. Spots that died out completely need re-sodding.
Does mowing spread it?
It can move on equipment, so we mow diseased areas last and keep our decks clean. Keeping your lawn healthy and correctly mowed is the bigger factor.
Related issues we can help with
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