Reversing Summer Fertilizer Damage on Cool-Season Grass

Applying weed-and-feed before a 90°F heat wave in Indiana burned a bluegrass/rye/fescue lawn. Immediate action: water deeply (1–2 hours) daily for several days to flush salts from root zone. Then water deeply twice weekly (1 hour each) through summer.

Do not fertilize cool-season grass in summer—ever. Fertilize late spring, early fall, late fall. Avoid weed-and-feed above 85°F; use spot-spray herbicide in spring/fall instead. Organic programs (sugar, compost, deep watering) prevent burn and build soil health.