Q: My lawn was just put in three months ago and it seems to be burned from the heat. We try to water it in the late afternoon when it's cooler, but it seems to be getting worse. Should we fertilize?
—Larry, Doylestown, Pennsylvania
A: Roger Cook replies: I would like you to water early in the morning instead of the afternoon. Watering in the afternoon can leave the grass blades wet all night, which can lead to fungus. This could be what you are seeing.
But if I had to guess, I would say it's probably a lack of fertilizer that's giving you this appearance. The lawn should have been fertilized twice by now, once 3 to 4 weeks after the initial fertilizing and again 6 to 8 weeks later. All the extra watering you're doing is leaching fertilizer out of the soil or driving it down beyond the development of the root system and making it unavailable to the grass. Try refertilizing with a starter fertilizer (low nitrogen, higher phosphorous). But be very careful when spreading it. These "burn" spots are sometimes areas where fertilizer has not been properly applied.