And welcome to MR19.

I was going to suggest the grass was not coming out of dormancy at the same time. Your ideas would be a good reason for that.

Do not apply chemical fertilizers in the summer. It would not necessarily cause the issue have, it is just not a good practice. Grass in the summer is stressed enough with the heat. Organic fertilizer can be applied in the summer or any time.

Last summer I followed the lead of a guru on another forum and fertilized with organic fertilizer every month. Actually he fertilized every week, but I did it every month. My lawn has never looked this good. It still looks great from last year. I had been starving my lawn with the fertilizer program I was on. You might try applying something like alfalfa pellets at 20-30 pounds per 1,000 square feet now and see what it looks like in a month.

It looks like you are mowing at your mower's lowest setting. Do you do that all year long? Your Kentucky bluegrass lawn should be mowed at one notch below the top setting on your mower.

How long does it take your sprinkler to fill a cat food can? There is no right or wrong answer to this. Mine takes 8 hours but some others take 15 minutes. 20 minutes might not be long enough. When you raise your mower 20 minutes might be enough. You'll have to adjust the watering once all the grass is up and getting mowed evenly.

Otherwise, your lawn looks pretty good compared to a lot of the lawns we see here. No weeds is an excellent achievement. Oh, how did you get to 'no weeds?'

My mower is set one notch below the middle, several notches from the top (not at home so can't check right now). I'll raise the deck for the next mow.

Don't have the sprinkler system turned on for the season yet but will check once I do.

As for the no weeds. There are some in there, but typically I pull or hand spray weeds during several times over the spring/summer/fall.

Thanks again guys, glad I found this board.