"My lawn has brown spots and watering more isn't helping." It's the most common call we get from June through September — and watering more is usually the wrong move, because the cause usually isn't drought.
The four usual suspects
1. Billbug damage
Idaho's most destructive lawn insect. Patches turn straw-brown in early-to-mid summer, and the dead grass pulls up easily like loose carpet with sawdust-like material at the base. Full billbug guide →
2. Sprinkler coverage gaps
Brown areas with sharp edges, often in the same shape season after season, between heads or along curbs. Run each zone and watch: a tilted head, clogged nozzle, or pressure issue shows up fast. Fix the coverage before assuming anything else.
3. Pet spots
Small dead circles with a dark-green ring around them — nitrogen burn from dog urine. Flush fresh spots with water; established spots need the dead turf raked out and reseeded.
4. Fungal disease
Irregular patches, rings, or matted gray-pink grass, usually in stretches of humid weather or on lawns watered nightly. Watering deeply but less often, and in the morning instead of evening, prevents most of it.
Repairing the damage
Once the cause is fixed, repair is straightforward: rake out dead material, rough up the soil, seed with a matching blend, topdress lightly, and keep it moist. Fall repairs establish best — see our overseeding guide.
Not sure which one you're looking at? That's literally what our complimentary lawn assessment is for — we diagnose before we recommend anything.
Frequently asked questions
Why does my lawn have brown patches even though I water it?
In the Treasure Valley the usual causes are billbug larvae, sprinkler coverage gaps, pet urine spots, or fungal disease. More water won't fix any of them, and in the case of disease it makes things worse.
How can I tell billbug damage from drought stress?
Use the tug test. Grab the grass at the edge of a brown patch and pull. Billbug-damaged turf lifts out with almost no root resistance and often has sawdust-like frass at the base. Drought-stressed grass stays firmly anchored.
Will brown patches recover on their own?
Only if the cause is removed. Patches from heat or a missed watering cycle usually recover once conditions improve. Damage from insects, disease, or a genuine coverage gap needs the underlying problem fixed, then reseeding or repair.