Why Is My Lawn Turning Brown During This Heatwave?

Brown grass during a Stillwater heatwave is not automatically dead grass. Dormancy, dry soil, uneven sprinkler coverage, disease, and insects can look similar. Check the conditions before adding fertilizer or another treatment.

Start with the pattern

Is the whole lawn fading, or are there isolated patches? Note the grass type, when the change began, recent mowing, irrigation, and any products applied. Photograph both the damaged area and nearby healthy turf.

A screwdriver can help compare soil resistance, but it cannot diagnose drought or compaction by itself. Check actual moisture below the surface and compare affected and unaffected areas.

Match mowing to the grass

Bermuda and tall fescue should not automatically receive the same mower setting. Use a height appropriate for the species, cultivar, and season, and avoid removing too much growth in one visit. A lawn that has stopped growing may not need mowing.

For local background, see OSU Extension's turfgrass management guidance.

Check irrigation before increasing runtime

Watch each zone for clogged or tilted heads, missed areas, leaks, and runoff. Early-morning watering is useful, but the amount and frequency should reflect rainfall, soil moisture, grass type, and any applicable watering restrictions. Newly seeded or newly sodded areas need a different establishment schedule from mature turf.

If water runs off before soaking in, shorter watering cycles with pauses may help. Persistent low spots or saturation need a separate drainage assessment.

Avoid treating an unidentified problem

Do not assume every brown patch needs fertilizer, fungicide, or insecticide. Heat- or drought-stressed grass may be injured by an unsuitable treatment. Follow the specific product label, including temperature restrictions, turf compatibility, and reentry instructions; there is no single temperature cutoff for every herbicide.

When to ask for help

Expanding patches, persistently wet soil, failed sprinkler coverage, or areas that do not recover deserve closer inspection. Send us photos and a brief maintenance history, or request a Stillwater lawn-care estimate. Our lawn care services can be planned around the cause rather than the color alone.